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2022-05-13mm/mprotect: use mmu_gatherNadav Amit1-1/+5
Patch series "mm/mprotect: avoid unnecessary TLB flushes", v6. This patchset is intended to remove unnecessary TLB flushes during mprotect() syscalls. Once this patch-set make it through, similar and further optimizations for MADV_COLD and userfaultfd would be possible. Basically, there are 3 optimizations in this patch-set: 1. Use TLB batching infrastructure to batch flushes across VMAs and do better/fewer flushes. This would also be handy for later userfaultfd enhancements. 2. Avoid unnecessary TLB flushes. This optimization is the one that provides most of the performance benefits. Unlike previous versions, we now only avoid flushes that would not result in spurious page-faults. 3. Avoiding TLB flushes on change_huge_pmd() that are only needed to prevent the A/D bits from changing. Andrew asked for some benchmark numbers. I do not have an easy determinate macrobenchmark in which it is easy to show benefit. I therefore ran a microbenchmark: a loop that does the following on anonymous memory, just as a sanity check to see that time is saved by avoiding TLB flushes. The loop goes: mprotect(p, PAGE_SIZE, PROT_READ) mprotect(p, PAGE_SIZE, PROT_READ|PROT_WRITE) *p = 0; // make the page writable The test was run in KVM guest with 1 or 2 threads (the second thread was busy-looping). I measured the time (cycles) of each operation: 1 thread 2 threads mmots +patch mmots +patch PROT_READ 3494 2725 (-22%) 8630 7788 (-10%) PROT_READ|WRITE 3952 2724 (-31%) 9075 2865 (-68%) [ mmots = v5.17-rc6-mmots-2022-03-06-20-38 ] The exact numbers are really meaningless, but the benefit is clear. There are 2 interesting results though. (1) PROT_READ is cheaper, while one can expect it not to be affected. This is presumably due to TLB miss that is saved (2) Without memory access (*p = 0), the speedup of the patch is even greater. In that scenario mprotect(PROT_READ) also avoids the TLB flush. As a result both operations on the patched kernel take roughly ~1500 cycles (with either 1 or 2 threads), whereas on mmotm their cost is as high as presented in the table. This patch (of 3): change_pXX_range() currently does not use mmu_gather, but instead implements its own deferred TLB flushes scheme. This both complicates the code, as developers need to be aware of different invalidation schemes, and prevents opportunities to avoid TLB flushes or perform them in finer granularity. The use of mmu_gather for modified PTEs has benefits in various scenarios even if pages are not released. For instance, if only a single page needs to be flushed out of a range of many pages, only that page would be flushed. If a THP page is flushed, on x86 a single TLB invlpg instruction can be used instead of 512 instructions (or a full TLB flush, which would Linux would actually use by default). mprotect() over multiple VMAs requires a single flush. Use mmu_gather in change_pXX_range(). As the pages are not released, only record the flushed range using tlb_flush_pXX_range(). Handle THP similarly and get rid of flush_cache_range() which becomes redundant since tlb_start_vma() calls it when needed. Link: https://lkml.kernel.org/r/20220401180821.1986781-1-namit@vmware.com Link: https://lkml.kernel.org/r/20220401180821.1986781-2-namit@vmware.com Signed-off-by: Nadav Amit <namit@vmware.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Peter Xu <peterx@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yu Zhao <yuzhao@google.com> Cc: Nick Piggin <npiggin@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-03-28Merge tag 'ptrace-cleanups-for-v5.18' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull ptrace cleanups from Eric Biederman: "This set of changes removes tracehook.h, moves modification of all of the ptrace fields inside of siglock to remove races, adds a missing permission check to ptrace.c The removal of tracehook.h is quite significant as it has been a major source of confusion in recent years. Much of that confusion was around task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the semantics clearer). For people who don't know tracehook.h is a vestiage of an attempt to implement uprobes like functionality that was never fully merged, and was later superseeded by uprobes when uprobes was merged. For many years now we have been removing what tracehook functionaly a little bit at a time. To the point where anything left in tracehook.h was some weird strange thing that was difficult to understand" * tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: ptrace: Remove duplicated include in ptrace.c ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE ptrace: Return the signal to continue with from ptrace_stop ptrace: Move setting/clearing ptrace_message into ptrace_stop tracehook: Remove tracehook.h resume_user_mode: Move to resume_user_mode.h resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume signal: Move set_notify_signal and clear_notify_signal into sched/signal.h task_work: Decouple TIF_NOTIFY_SIGNAL and task_work task_work: Call tracehook_notify_signal from get_signal on all architectures task_work: Introduce task_work_pending task_work: Remove unnecessary include from posix_timers.h ptrace: Remove tracehook_signal_handler ptrace: Remove arch_syscall_{enter,exit}_tracehook ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h ptrace/arm: Rename tracehook_report_syscall report_syscall ptrace: Move ptrace_report_syscall into ptrace.h
2022-03-23Merge tag 'asm-generic-5.18' of ↵Linus Torvalds1-6/+0
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "There are three sets of updates for 5.18 in the asm-generic tree: - The set_fs()/get_fs() infrastructure gets removed for good. This was already gone from all major architectures, but now we can finally remove it everywhere, which loses some particularly tricky and error-prone code. There is a small merge conflict against a parisc cleanup, the solution is to use their new version. - The nds32 architecture ends its tenure in the Linux kernel. The hardware is still used and the code is in reasonable shape, but the mainline port is not actively maintained any more, as all remaining users are thought to run vendor kernels that would never be updated to a future release. - A series from Masahiro Yamada cleans up some of the uapi header files to pass the compile-time checks" * tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (27 commits) nds32: Remove the architecture uaccess: remove CONFIG_SET_FS ia64: remove CONFIG_SET_FS support sh: remove CONFIG_SET_FS support sparc64: remove CONFIG_SET_FS support lib/test_lockup: fix kernel pointer check for separate address spaces uaccess: generalize access_ok() uaccess: fix type mismatch warnings from access_ok() arm64: simplify access_ok() m68k: fix access_ok for coldfire MIPS: use simpler access_ok() MIPS: Handle address errors for accesses above CPU max virtual user address uaccess: add generic __{get,put}_kernel_nofault nios2: drop access_ok() check from __put_user() x86: use more conventional access_ok() definition x86: remove __range_not_ok() sparc64: add __{get,put}_kernel_nofault() nds32: fix access_ok() checks in get/put_user uaccess: fix nios2 and microblaze get_user_8() sparc64: fix building assembly files ...
2022-03-10tracehook: Remove tracehook.hEric W. Biederman1-1/+0
Now that all of the definitions have moved out of tracehook.h into ptrace.h, sched/signal.h, resume_user_mode.h there is nothing left in tracehook.h so remove it. Update the few files that were depending upon tracehook.h to bring in definitions to use the headers they need directly. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-13-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-03-01exec: cleanup commentsTom Rix1-3/+3
Remove the second 'from'. Replace 'backwords' with 'backwards'. Replace 'visibile' with 'visible'. Signed-off-by: Tom Rix <trix@redhat.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220211160940.2516243-1-trix@redhat.com
2022-03-01exec: Force single empty string when argv is emptyKees Cook1-1/+25
Quoting[1] Ariadne Conill: "In several other operating systems, it is a hard requirement that the second argument to execve(2) be the name of a program, thus prohibiting a scenario where argc < 1. POSIX 2017 also recommends this behaviour, but it is not an explicit requirement[2]: The argument arg0 should point to a filename string that is associated with the process being started by one of the exec functions. ... Interestingly, Michael Kerrisk opened an issue about this in 2008[3], but there was no consensus to support fixing this issue then. Hopefully now that CVE-2021-4034 shows practical exploitative use[4] of this bug in a shellcode, we can reconsider. This issue is being tracked in the KSPP issue tracker[5]." While the initial code searches[6][7] turned up what appeared to be mostly corner case tests, trying to that just reject argv == NULL (or an immediately terminated pointer list) quickly started tripping[8] existing userspace programs. The next best approach is forcing a single empty string into argv and adjusting argc to match. The number of programs depending on argc == 0 seems a smaller set than those calling execve with a NULL argv. Account for the additional stack space in bprm_stack_limits(). Inject an empty string when argc == 0 (and set argc = 1). Warn about the case so userspace has some notice about the change: process './argc0' launched './argc0' with NULL argv: empty string added Additionally WARN() and reject NULL argv usage for kernel threads. [1] https://lore.kernel.org/lkml/20220127000724.15106-1-ariadne@dereferenced.org/ [2] https://pubs.opengroup.org/onlinepubs/9699919799/functions/exec.html [3] https://bugzilla.kernel.org/show_bug.cgi?id=8408 [4] https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt [5] https://github.com/KSPP/linux/issues/176 [6] https://codesearch.debian.net/search?q=execve%5C+*%5C%28%5B%5E%2C%5D%2B%2C+*NULL&literal=0 [7] https://codesearch.debian.net/search?q=execlp%3F%5Cs*%5C%28%5B%5E%2C%5D%2B%2C%5Cs*NULL&literal=0 [8] https://lore.kernel.org/lkml/20220131144352.GE16385@xsang-OptiPlex-9020/ Reported-by: Ariadne Conill <ariadne@dereferenced.org> Reported-by: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Rich Felker <dalias@libc.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: Ariadne Conill <ariadne@dereferenced.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20220201000947.2453721-1-keescook@chromium.org
2022-02-25uaccess: remove CONFIG_SET_FSArnd Bergmann1-6/+0
There are no remaining callers of set_fs(), so CONFIG_SET_FS can be removed globally, along with the thread_info field and any references to it. This turns access_ok() into a cheaper check against TASK_SIZE_MAX. As CONFIG_SET_FS is now gone, drop all remaining references to set_fs()/get_fs(), mm_segment_t, user_addr_max() and uaccess_kernel(). Acked-by: Sam Ravnborg <sam@ravnborg.org> # for sparc32 changes Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Tested-by: Sergey Matyukevich <sergey.matyukevich@synopsys.com> # for arc changes Acked-by: Stafford Horne <shorne@gmail.com> # [openrisc, asm-generic] Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-01-22fs/coredump: move coredump sysctls into its own fileXiaoming Ni1-55/+0
This moves the fs/coredump.c respective sysctls to its own file. Link: https://lkml.kernel.org/r/20211129211943.640266-6-mcgrof@kernel.org Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Antti Palosaari <crope@iki.fi> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Iurii Zaikin <yzaikin@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: Lukas Middendorf <kernel@tuxforce.de> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Stephen Kitt <steve@sk2.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-22fs: move fs/exec.c sysctls into its own fileLuis Chamberlain1-0/+90
kernel/sysctl.c is a kitchen sink where everyone leaves their dirty dishes, this makes it very difficult to maintain. To help with this maintenance let's start by moving sysctls to places where they actually belong. The proc sysctl maintainers do not want to know what sysctl knobs you wish to add for your own piece of code, we just care about the core logic. So move the fs/exec.c respective sysctls to its own file. Since checkpatch complains about style issues with the old code, this move also fixes a few of those minor style issues: * Use pr_warn() instead of prink(WARNING * New empty lines are wanted at the beginning of routines Link: https://lkml.kernel.org/r/20211129205548.605569-9-mcgrof@kernel.org Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Antti Palosaari <crope@iki.fi> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Iurii Zaikin <yzaikin@google.com> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Jeff Layton <jlayton@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Lukas Middendorf <kernel@tuxforce.de> Cc: Stephen Kitt <steve@sk2.org> Cc: Xiaoming Ni <nixiaoming@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-20Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-2/+3
Merge more updates from Andrew Morton: "55 patches. Subsystems affected by this patch series: percpu, procfs, sysctl, misc, core-kernel, get_maintainer, lib, checkpatch, binfmt, nilfs2, hfs, fat, adfs, panic, delayacct, kconfig, kcov, and ubsan" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (55 commits) lib: remove redundant assignment to variable ret ubsan: remove CONFIG_UBSAN_OBJECT_SIZE kcov: fix generic Kconfig dependencies if ARCH_WANTS_NO_INSTR lib/Kconfig.debug: make TEST_KMOD depend on PAGE_SIZE_LESS_THAN_256KB btrfs: use generic Kconfig option for 256kB page size limit arch/Kconfig: split PAGE_SIZE_LESS_THAN_256KB from PAGE_SIZE_LESS_THAN_64KB configs: introduce debug.config for CI-like setup delayacct: track delays from memory compact Documentation/accounting/delay-accounting.rst: add thrashing page cache and direct compact delayacct: cleanup flags in struct task_delay_info and functions use it delayacct: fix incomplete disable operation when switch enable to disable delayacct: support swapin delay accounting for swapping without blkio panic: remove oops_id panic: use error_report_end tracepoint on warnings fs/adfs: remove unneeded variable make code cleaner FAT: use io_schedule_timeout() instead of congestion_wait() hfsplus: use struct_group_attr() for memcpy() region nilfs2: remove redundant pointer sbufs fs/binfmt_elf: use PT_LOAD p_align values for static PIE const_structs.checkpatch: add frequently used ops structs ...
2022-01-20fs/exec: replace strncpy with strscpy_pad in __get_task_commYafang Shao1-1/+2
If the dest buffer size is smaller than sizeof(tsk->comm), the buffer will be without null ternimator, that may cause problem. Using strscpy_pad() instead of strncpy() in __get_task_comm() can make the string always nul ternimated and zero padded. Link: https://lkml.kernel.org/r/20211120112738.45980-3-laoar.shao@gmail.com Suggested-by: Kees Cook <keescook@chromium.org> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com> Cc: Michal Miroslaw <mirq-linux@rere.qmqm.pl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-20fs/exec: replace strlcpy with strscpy_pad in __set_task_commYafang Shao1-1/+1
Patch series "task comm cleanups", v2. This patchset is part of the patchset "extend task comm from 16 to 24"[1]. Now we have different opinion that dynamically allocates memory to store kthread's long name into a separate pointer, so I decide to take the useful cleanups apart from the original patchset and send it separately[2]. These useful cleanups can make the usage around task comm less error-prone. Furthermore, it will be useful if we want to extend task comm in the future. [1]. https://lore.kernel.org/lkml/20211101060419.4682-1-laoar.shao@gmail.com/ [2]. https://lore.kernel.org/lkml/CALOAHbAx55AUo3bm8ZepZSZnw7A08cvKPdPyNTf=E_tPqmw5hw@mail.gmail.com/ This patch (of 7): strlcpy() can trigger out-of-bound reads on the source string[1], we'd better use strscpy() instead. To make it be robust against full tsk->comm copies that got noticed in other places, we should make sure it's zero padded. [1] https://github.com/KSPP/linux/issues/89 Link: https://lkml.kernel.org/r/20211120112738.45980-1-laoar.shao@gmail.com Link: https://lkml.kernel.org/r/20211120112738.45980-2-laoar.shao@gmail.com Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com> Cc: Michal Miroslaw <mirq-linux@rere.qmqm.pl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-08signal: Remove the helper signal_group_exitEric W. Biederman1-1/+1
This helper is misleading. It tests for an ongoing exec as well as the process having received a fatal signal. Sometimes it is appropriate to treat an on-going exec differently than a process that is shutting down due to a fatal signal. In particular taking the fast path out of exit_signals instead of retargeting signals is not appropriate during exec, and not changing the the exit code in do_group_exit during exec. Removing the helper makes it more obvious what is going on as both cases must be coded for explicitly. While removing the helper fix the two cases where I have observed using signal_group_exit resulted in the wrong result. In exit_signals only test for SIGNAL_GROUP_EXIT so that signals are retargetted during an exec. In do_group_exit use 0 as the exit code during an exec as de_thread does not set group_exit_code. As best as I can determine group_exit_code has been is set to 0 most of the time during de_thread. During a thread group stop group_exit_code is set to the stop signal and when the thread group receives SIGCONT group_exit_code is reset to 0. Link: https://lkml.kernel.org/r/20211213225350.27481-8-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-01-08signal: Rename group_exit_task group_exec_taskEric W. Biederman1-4/+4
The only remaining user of group_exit_task is exec. Rename the field so that it is clear which part of the code uses it. Update the comment above the definition of group_exec_task to document how it is currently used. Link: https://lkml.kernel.org/r/20211213225350.27481-7-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-12-13kthread: Ensure struct kthread is present for all kthreadsEric W. Biederman1-0/+2
Today the rules are a bit iffy and arbitrary about which kernel threads have struct kthread present. Both idle threads and thread started with create_kthread want struct kthread present so that is effectively all kernel threads. Make the rule that if PF_KTHREAD and the task is running then struct kthread is present. This will allow the kernel thread code to using tsk->exit_code with different semantics from ordinary processes. To make ensure that struct kthread is present for all kernel threads move it's allocation into copy_process. Add a deallocation of struct kthread in exec for processes that were kernel threads. Move the allocation of struct kthread for the initial thread earlier so that it is not repeated for each additional idle thread. Move the initialization of struct kthread into set_kthread_struct so that the structure is always and reliably initailized. Clear set_child_tid in free_kthread_struct to ensure the kthread struct is reliably freed during exec. The function free_kthread_struct does not need to clear vfork_done during exec as exec_mm_release called from exec_mmap has already cleared vfork_done. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-11-10Merge branch 'exit-cleanups-for-v5.16' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull exit cleanups from Eric Biederman: "While looking at some issues related to the exit path in the kernel I found several instances where the code is not using the existing abstractions properly. This set of changes introduces force_fatal_sig a way of sending a signal and not allowing it to be caught, and corrects the misuse of the existing abstractions that I found. A lot of the misuse of the existing abstractions are silly things such as doing something after calling a no return function, rolling BUG by hand, doing more work than necessary to terminate a kernel thread, or calling do_exit(SIGKILL) instead of calling force_sig(SIGKILL). In the review a deficiency in force_fatal_sig and force_sig_seccomp where ptrace or sigaction could prevent the delivery of the signal was found. I have added a change that adds SA_IMMUTABLE to change that makes it impossible to interrupt the delivery of those signals, and allows backporting to fix force_sig_seccomp And Arnd found an issue where a function passed to kthread_run had the wrong prototype, and after my cleanup was failing to build." * 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (23 commits) soc: ti: fix wkup_m3_rproc_boot_thread return type signal: Add SA_IMMUTABLE to ensure forced siganls do not get changed signal: Replace force_sigsegv(SIGSEGV) with force_fatal_sig(SIGSEGV) exit/r8188eu: Replace the macro thread_exit with a simple return 0 exit/rtl8712: Replace the macro thread_exit with a simple return 0 exit/rtl8723bs: Replace the macro thread_exit with a simple return 0 signal/x86: In emulate_vsyscall force a signal instead of calling do_exit signal/sparc32: In setup_rt_frame and setup_fram use force_fatal_sig signal/sparc32: Exit with a fatal signal when try_to_clear_window_buffer fails exit/syscall_user_dispatch: Send ordinary signals on failure signal: Implement force_fatal_sig exit/kthread: Have kernel threads return instead of calling do_exit signal/s390: Use force_sigsegv in default_trap_handler signal/vm86_32: Properly send SIGSEGV when the vm86 state cannot be saved. signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ON signal/sparc: In setup_tsb_params convert open coded BUG into BUG signal/powerpc: On swapcontext failure force SIGSEGV signal/sh: Use force_sig(SIGKILL) instead of do_group_exit(SIGKILL) signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT signal/sparc32: Remove unreachable do_exit in do_sparc_fault ...
2021-10-29signal: Replace force_sigsegv(SIGSEGV) with force_fatal_sig(SIGSEGV)Eric W. Biederman1-1/+1
Now that force_fatal_sig exists it is unnecessary and a bit confusing to use force_sigsegv in cases where the simpler force_fatal_sig is wanted. So change every instance we can to make the code clearer. Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Link: https://lkml.kernel.org/r/877de7jrev.fsf@disp2133 Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-10-06exec: Check for a pending fatal signal instead of core_stateEric W. Biederman1-8/+6
Prevent exec continuing when a fatal signal is pending by replacing mmap_read_lock with mmap_read_lock_killable. This is always the right thing to do as userspace will never observe an exec complete when there is a fatal signal pending. With that change it becomes unnecessary to explicitly test for a core dump in progress. In coredump_wait zap_threads arranges under mmap_write_lock for all tasks that use a mm to also have SIGKILL pending, which means mmap_read_lock_killable will always return -EINTR when old_mm->core_state is present. Link: https://lkml.kernel.org/r/87fstux27w.fsf@disp2133 Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-09-04Merge tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linuxLinus Torvalds1-1/+3
Pull MAP_DENYWRITE removal from David Hildenbrand: "Remove all in-tree usage of MAP_DENYWRITE from the kernel and remove VM_DENYWRITE. There are some (minor) user-visible changes: - We no longer deny write access to shared libaries loaded via legacy uselib(); this behavior matches modern user space e.g. dlopen(). - We no longer deny write access to the elf interpreter after exec completed, treating it just like shared libraries (which it often is). - We always deny write access to the file linked via /proc/pid/exe: sys_prctl(PR_SET_MM_MAP/EXE_FILE) will fail if write access to the file cannot be denied, and write access to the file will remain denied until the link is effectivel gone (exec, termination, sys_prctl(PR_SET_MM_MAP/EXE_FILE)) -- just as if exec'ing the file. Cross-compiled for a bunch of architectures (alpha, microblaze, i386, s390x, ...) and verified via ltp that especially the relevant tests (i.e., creat07 and execve04) continue working as expected" * tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux: fs: update documentation of get_write_access() and friends mm: ignore MAP_DENYWRITE in ksys_mmap_pgoff() mm: remove VM_DENYWRITE binfmt: remove in-tree usage of MAP_DENYWRITE kernel/fork: always deny write access to current MM exe_file kernel/fork: factor out replacing the current MM exe_file binfmt: don't use MAP_DENYWRITE when loading shared libraries via uselib()
2021-09-03Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-3/+5
Merge misc updates from Andrew Morton: "173 patches. Subsystems affected by this series: ia64, ocfs2, block, and mm (debug, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock, oom-kill, migration, ksm, percpu, vmstat, and madvise)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits) mm/madvise: add MADV_WILLNEED to process_madvise() mm/vmstat: remove unneeded return value mm/vmstat: simplify the array size calculation mm/vmstat: correct some wrong comments mm/percpu,c: remove obsolete comments of pcpu_chunk_populated() selftests: vm: add COW time test for KSM pages selftests: vm: add KSM merging time test mm: KSM: fix data type selftests: vm: add KSM merging across nodes test selftests: vm: add KSM zero page merging test selftests: vm: add KSM unmerge test selftests: vm: add KSM merge test mm/migrate: correct kernel-doc notation mm: wire up syscall process_mrelease mm: introduce process_mrelease system call memblock: make memblock_find_in_range method private mm/mempolicy.c: use in_task() in mempolicy_slab_node() mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies mm/mempolicy: advertise new MPOL_PREFERRED_MANY mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY ...
2021-09-03mm/pagemap: add mmap_assert_locked() annotations to find_vma*()Luigi Rizzo1-0/+2
find_vma() and variants need protection when used. This patch adds mmap_assert_lock() calls in the functions. To make sure the invariant is satisfied, we also need to add a mmap_read_lock() around the get_user_pages_remote() call in get_arg_page(). The lock is not strictly necessary because the mm has been newly created, but the extra cost is limited because the same mutex was also acquired shortly before in __bprm_mm_init(), so it is hot and uncontended. [penguin-kernel@i-love.sakura.ne.jp: TOMOYO needs the same protection which get_arg_page() needs] Link: https://lkml.kernel.org/r/58bb6bf7-a57e-8a40-e74b-39584b415152@i-love.sakura.ne.jp Link: https://lkml.kernel.org/r/20210731175341.3458608-1-lrizzo@google.com Signed-off-by: Luigi Rizzo <lrizzo@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03mm: remove flush_kernel_dcache_pageChristoph Hellwig1-3/+3
flush_kernel_dcache_page is a rather confusing interface that implements a subset of flush_dcache_page by not being able to properly handle page cache mapped pages. The only callers left are in the exec code as all other previous callers were incorrect as they could have dealt with page cache pages. Replace the calls to flush_kernel_dcache_page with calls to flush_dcache_page, which for all architectures does either exactly the same thing, can contains one or more of the following: 1) an optimization to defer the cache flush for page cache pages not mapped into userspace 2) additional flushing for mapped page cache pages if cache aliases are possible Link: https://lkml.kernel.org/r/20210712060928.4161649-7-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Cc: Alex Shi <alexs@kernel.org> Cc: Geoff Levand <geoff@infradead.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Guo Ren <guoren@kernel.org> Cc: Helge Deller <deller@gmx.de> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Cercueil <paul@crapouillou.net> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03kernel/fork: always deny write access to current MM exe_fileDavid Hildenbrand1-1/+3
We want to remove VM_DENYWRITE only currently only used when mapping the executable during exec. During exec, we already deny_write_access() the executable, however, after exec completes the VMAs mapped with VM_DENYWRITE effectively keeps write access denied via deny_write_access(). Let's deny write access when setting or replacing the MM exe_file. With this change, we can remove VM_DENYWRITE for mapping executables. Make set_mm_exe_file() return an error in case deny_write_access() fails; note that this should never happen, because exec code does a deny_write_access() early and keeps write access denied when calling set_mm_exe_file. However, it makes the code easier to read and makes set_mm_exe_file() and replace_mm_exe_file() look more similar. This represents a minor user space visible change: sys_prctl(PR_SET_MM_MAP/EXE_FILE) can now fail if the file is already opened writable. Also, after sys_prctl(PR_SET_MM_MAP/EXE_FILE) the file cannot be opened writable. Note that we can already fail with -EACCES if the file doesn't have execute permissions. Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Christian König <christian.koenig@amd.com> Signed-off-by: David Hildenbrand <david@redhat.com>
2021-08-23namei: add getname_uflags()Dmitry Kadashev1-6/+2
There are a couple of places where we already open-code the (flags & AT_EMPTY_PATH) check and io_uring will likely add another one in the future. Let's just add a simple helper getname_uflags() that handles this directly and use it. Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/io-uring/20210415100815.edrn4a7cy26wkowe@wittgenstein/ Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Dmitry Kadashev <dkadashev@gmail.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Link: https://lore.kernel.org/r/20210708063447.3556403-7-dkadashev@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-02Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-3/+0
Merge more updates from Andrew Morton: "190 patches. Subsystems affected by this patch series: mm (hugetlb, userfaultfd, vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock, migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap, zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc, core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs, signals, exec, kcov, selftests, compress/decompress, and ipc" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits) ipc/util.c: use binary search for max_idx ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock ipc: use kmalloc for msg_queue and shmid_kernel ipc sem: use kvmalloc for sem_undo allocation lib/decompressors: remove set but not used variabled 'level' selftests/vm/pkeys: exercise x86 XSAVE init state selftests/vm/pkeys: refill shadow register after implicit kernel write selftests/vm/pkeys: handle negative sys_pkey_alloc() return code selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random kcov: add __no_sanitize_coverage to fix noinstr for all architectures exec: remove checks in __register_bimfmt() x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned hfsplus: report create_date to kstat.btime hfsplus: remove unnecessary oom message nilfs2: remove redundant continue statement in a while-loop kprobes: remove duplicated strong free_insn_page in x86 and s390 init: print out unknown kernel parameters checkpatch: do not complain about positive return values starting with EPOLL checkpatch: improve the indented label test checkpatch: scripts/spdxcheck.py now requires python3 ...
2021-07-01exec: remove checks in __register_bimfmt()Alexey Dobriyan1-3/+0
Delete NULL check, all callers pass valid pointer. Delete ->load_binary check -- failure to provide hook in a custom module will be very noticeable at the very first execve call. Link: https://lkml.kernel.org/r/YK1Gy1qXaLAR+tPl@localhost.localdomain Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30Reimplement RLIMIT_NPROC on top of ucountsAlexey Gladkov1-1/+1
The rlimit counter is tied to uid in the user_namespace. This allows rlimit values to be specified in userns even if they are already globally exceeded by the user. However, the value of the previous user_namespaces cannot be exceeded. To illustrate the impact of rlimits, let's say there is a program that does not fork. Some service-A wants to run this program as user X in multiple containers. Since the program never fork the service wants to set RLIMIT_NPROC=1. service-A \- program (uid=1000, container1, rlimit_nproc=1) \- program (uid=1000, container2, rlimit_nproc=1) The service-A sets RLIMIT_NPROC=1 and runs the program in container1. When the service-A tries to run a program with RLIMIT_NPROC=1 in container2 it fails since user X already has one running process. We cannot use existing inc_ucounts / dec_ucounts because they do not allow us to exceed the maximum for the counter. Some rlimits can be overlimited by root or if the user has the appropriate capability. Changelog v11: * Change inc_rlimit_ucounts() which now returns top value of ucounts. * Drop inc_rlimit_ucounts_and_test() because the return code of inc_rlimit_ucounts() can be checked. Signed-off-by: Alexey Gladkov <legion@kernel.org> Link: https://lkml.kernel.org/r/c5286a8aa16d2d698c222f7532f3d735c82bc6bc.1619094428.git.legion@kernel.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2021-04-30Add a reference to ucounts for each credAlexey Gladkov1-0/+4
For RLIMIT_NPROC and some other rlimits the user_struct that holds the global limit is kept alive for the lifetime of a process by keeping it in struct cred. Adding a pointer to ucounts in the struct cred will allow to track RLIMIT_NPROC not only for user in the system, but for user in the user_namespace. Updating ucounts may require memory allocation which may fail. So, we cannot change cred.ucounts in the commit_creds() because this function cannot fail and it should always return 0. For this reason, we modify cred.ucounts before calling the commit_creds(). Changelog v6: * Fix null-ptr-deref in is_ucounts_overlimit() detected by trinity. This error was caused by the fact that cred_alloc_blank() left the ucounts pointer empty. Reported-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Alexey Gladkov <legion@kernel.org> Link: https://lkml.kernel.org/r/b37aaef28d8b9b0d757e07ba6dd27281bbe39259.1619094428.git.legion@kernel.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2021-02-24fs: delete repeated words in commentsRandy Dunlap1-2/+2
Delete duplicate words in fs/*.c. The doubled words that are being dropped are: that, be, the, in, and, for Link: https://lkml.kernel.org/r/20201224052810.25315-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-23Merge tag 'idmapped-mounts-v5.12' of ↵Linus Torvalds1-4/+8
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull idmapped mounts from Christian Brauner: "This introduces idmapped mounts which has been in the making for some time. Simply put, different mounts can expose the same file or directory with different ownership. This initial implementation comes with ports for fat, ext4 and with Christoph's port for xfs with more filesystems being actively worked on by independent people and maintainers. Idmapping mounts handle a wide range of long standing use-cases. Here are just a few: - Idmapped mounts make it possible to easily share files between multiple users or multiple machines especially in complex scenarios. For example, idmapped mounts will be used in the implementation of portable home directories in systemd-homed.service(8) where they allow users to move their home directory to an external storage device and use it on multiple computers where they are assigned different uids and gids. This effectively makes it possible to assign random uids and gids at login time. - It is possible to share files from the host with unprivileged containers without having to change ownership permanently through chown(2). - It is possible to idmap a container's rootfs and without having to mangle every file. For example, Chromebooks use it to share the user's Download folder with their unprivileged containers in their Linux subsystem. - It is possible to share files between containers with non-overlapping idmappings. - Filesystem that lack a proper concept of ownership such as fat can use idmapped mounts to implement discretionary access (DAC) permission checking. - They allow users to efficiently changing ownership on a per-mount basis without having to (recursively) chown(2) all files. In contrast to chown (2) changing ownership of large sets of files is instantenous with idmapped mounts. This is especially useful when ownership of a whole root filesystem of a virtual machine or container is changed. With idmapped mounts a single syscall mount_setattr syscall will be sufficient to change the ownership of all files. - Idmapped mounts always take the current ownership into account as idmappings specify what a given uid or gid is supposed to be mapped to. This contrasts with the chown(2) syscall which cannot by itself take the current ownership of the files it changes into account. It simply changes the ownership to the specified uid and gid. This is especially problematic when recursively chown(2)ing a large set of files which is commong with the aforementioned portable home directory and container and vm scenario. - Idmapped mounts allow to change ownership locally, restricting it to specific mounts, and temporarily as the ownership changes only apply as long as the mount exists. Several userspace projects have either already put up patches and pull-requests for this feature or will do so should you decide to pull this: - systemd: In a wide variety of scenarios but especially right away in their implementation of portable home directories. https://systemd.io/HOME_DIRECTORY/ - container runtimes: containerd, runC, LXD:To share data between host and unprivileged containers, unprivileged and privileged containers, etc. The pull request for idmapped mounts support in containerd, the default Kubernetes runtime is already up for quite a while now: https://github.com/containerd/containerd/pull/4734 - The virtio-fs developers and several users have expressed interest in using this feature with virtual machines once virtio-fs is ported. - ChromeOS: Sharing host-directories with unprivileged containers. I've tightly synced with all those projects and all of those listed here have also expressed their need/desire for this feature on the mailing list. For more info on how people use this there's a bunch of talks about this too. Here's just two recent ones: https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdf https://fosdem.org/2021/schedule/event/containers_idmap/ This comes with an extensive xfstests suite covering both ext4 and xfs: https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts It covers truncation, creation, opening, xattrs, vfscaps, setid execution, setgid inheritance and more both with idmapped and non-idmapped mounts. It already helped to discover an unrelated xfs setgid inheritance bug which has since been fixed in mainline. It will be sent for inclusion with the xfstests project should you decide to merge this. In order to support per-mount idmappings vfsmounts are marked with user namespaces. The idmapping of the user namespace will be used to map the ids of vfs objects when they are accessed through that mount. By default all vfsmounts are marked with the initial user namespace. The initial user namespace is used to indicate that a mount is not idmapped. All operations behave as before and this is verified in the testsuite. Based on prior discussions we want to attach the whole user namespace and not just a dedicated idmapping struct. This allows us to reuse all the helpers that already exist for dealing with idmappings instead of introducing a whole new range of helpers. In addition, if we decide in the future that we are confident enough to enable unprivileged users to setup idmapped mounts the permission checking can take into account whether the caller is privileged in the user namespace the mount is currently marked with. The user namespace the mount will be marked with can be specified by passing a file descriptor refering to the user namespace as an argument to the new mount_setattr() syscall together with the new MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern of extensibility. The following conditions must be met in order to create an idmapped mount: - The caller must currently have the CAP_SYS_ADMIN capability in the user namespace the underlying filesystem has been mounted in. - The underlying filesystem must support idmapped mounts. - The mount must not already be idmapped. This also implies that the idmapping of a mount cannot be altered once it has been idmapped. - The mount must be a detached/anonymous mount, i.e. it must have been created by calling open_tree() with the OPEN_TREE_CLONE flag and it must not already have been visible in the filesystem. The last two points guarantee easier semantics for userspace and the kernel and make the implementation significantly simpler. By default vfsmounts are marked with the initial user namespace and no behavioral or performance changes are observed. The manpage with a detailed description can be found here: https://git.kernel.org/brauner/man-pages/c/1d7b902e2875a1ff342e036a9f866a995640aea8 In order to support idmapped mounts, filesystems need to be changed and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The patches to convert individual filesystem are not very large or complicated overall as can be seen from the included fat, ext4, and xfs ports. Patches for other filesystems are actively worked on and will be sent out separately. The xfstestsuite can be used to verify that port has been done correctly. The mount_setattr() syscall is motivated independent of the idmapped mounts patches and it's been around since July 2019. One of the most valuable features of the new mount api is the ability to perform mounts based on file descriptors only. Together with the lookup restrictions available in the openat2() RESOLVE_* flag namespace which we added in v5.6 this is the first time we are close to hardened and race-free (e.g. symlinks) mounting and path resolution. While userspace has started porting to the new mount api to mount proper filesystems and create new bind-mounts it is currently not possible to change mount options of an already existing bind mount in the new mount api since the mount_setattr() syscall is missing. With the addition of the mount_setattr() syscall we remove this last restriction and userspace can now fully port to the new mount api, covering every use-case the old mount api could. We also add the crucial ability to recursively change mount options for a whole mount tree, both removing and adding mount options at the same time. This syscall has been requested multiple times by various people and projects. There is a simple tool available at https://github.com/brauner/mount-idmapped that allows to create idmapped mounts so people can play with this patch series. I'll add support for the regular mount binary should you decide to pull this in the following weeks: Here's an example to a simple idmapped mount of another user's home directory: u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt u1001@f2-vm:/$ ls -al /home/ubuntu/ total 28 drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 . drwxr-xr-x 4 root root 4096 Oct 28 04:00 .. -rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history -rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout -rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc -rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile -rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful -rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo u1001@f2-vm:/$ ls -al /mnt/ total 28 drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 . drwxr-xr-x 29 root root 4096 Oct 28 22:01 .. -rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history -rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout -rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc -rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile -rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful -rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo u1001@f2-vm:/$ touch /mnt/my-file u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file u1001@f2-vm:/$ ls -al /mnt/my-file -rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file u1001@f2-vm:/$ ls -al /home/ubuntu/my-file -rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file u1001@f2-vm:/$ getfacl /mnt/my-file getfacl: Removing leading '/' from absolute path names # file: mnt/my-file # owner: u1001 # group: u1001 user::rw- user:u1001:rwx group::rw- mask::rwx other::r-- u1001@f2-vm:/$ getfacl /home/ubuntu/my-file getfacl: Removing leading '/' from absolute path names # file: home/ubuntu/my-file # owner: ubuntu # group: ubuntu user::rw- user:ubuntu:rwx group::rw- mask::rwx other::r--" * tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits) xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl xfs: support idmapped mounts ext4: support idmapped mounts fat: handle idmapped mounts tests: add mount_setattr() selftests fs: introduce MOUNT_ATTR_IDMAP fs: add mount_setattr() fs: add attr_flags_to_mnt_flags helper fs: split out functions to hold writers namespace: only take read lock in do_reconfigure_mnt() mount: make {lock,unlock}_mount_hash() static namespace: take lock_mount_hash() directly when changing flags nfs: do not export idmapped mounts overlayfs: do not mount on top of idmapped mounts ecryptfs: do not mount on top of idmapped mounts ima: handle idmapped mounts apparmor: handle idmapped mounts fs: make helpers idmap mount aware exec: handle idmapped mounts would_dump: handle idmapped mounts ...
2021-01-29tlb: mmu_gather: Remove start/end arguments from tlb_gather_mmu()Will Deacon1-1/+1
The 'start' and 'end' arguments to tlb_gather_mmu() are no longer needed now that there is a separate function for 'fullmm' flushing. Remove the unused arguments and update all callers. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Yu Zhao <yuzhao@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/CAHk-=wjQWa14_4UpfDf=fiineNP+RH74kZeDMo_f1D35xNzq9w@mail.gmail.com
2021-01-29tlb: mmu_gather: Remove unused start/end arguments from tlb_finish_mmu()Will Deacon1-1/+1
Since commit 7a30df49f63a ("mm: mmu_gather: remove __tlb_reset_range() for force flush"), the 'start' and 'end' arguments to tlb_finish_mmu() are no longer used, since we flush the whole mm in case of a nested invalidation. Remove the unused arguments and update all callers. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Yu Zhao <yuzhao@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/20210127235347.1402-3-will@kernel.org
2021-01-24exec: handle idmapped mountsChristian Brauner1-2/+5
When executing a setuid binary the kernel will verify in bprm_fill_uid() that the inode has a mapping in the caller's user namespace before setting the callers uid and gid. Let bprm_fill_uid() handle idmapped mounts. If the inode is accessed through an idmapped mount it is mapped according to the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-24-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24would_dump: handle idmapped mountsChristian Brauner1-3/+3
When determining whether or not to create a coredump the vfs will verify that the caller is privileged over the inode. Make the would_dump() helper handle idmapped mounts by passing down the mount's user namespace of the exec file. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-23-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24namei: make permission helpers idmapped mount awareChristian Brauner1-1/+1
The two helpers inode_permission() and generic_permission() are used by the vfs to perform basic permission checking by verifying that the caller is privileged over an inode. In order to handle idmapped mounts we extend the two helpers with an additional user namespace argument. On idmapped mounts the two helpers will make sure to map the inode according to the mount's user namespace and then peform identical permission checks to inode_permission() and generic_permission(). If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24capability: handle idmapped mountsChristian Brauner1-1/+2
In order to determine whether a caller holds privilege over a given inode the capability framework exposes the two helpers privileged_wrt_inode_uidgid() and capable_wrt_inode_uidgid(). The former verifies that the inode has a mapping in the caller's user namespace and the latter additionally verifies that the caller has the requested capability in their current user namespace. If the inode is accessed through an idmapped mount map it into the mount's user namespace. Afterwards the checks are identical to non-idmapped inodes. If the initial user namespace is passed all operations are a nop so non-idmapped mounts will not see a change in behavior. Link: https://lore.kernel.org/r/20210121131959.646623-5-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-12-16Merge branch 'parisc-5.11-1' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux Pull parisc updates from Helge Deller: "A change to increase the default maximum stack size on parisc to 100MB and the ability to further increase the stack hard limit size at runtime with ulimit for newly started processes. The other patches fix compile warnings, utilize the Kbuild logic and cleanups the parisc arch code" * 'parisc-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: parisc: pci-dma: fix warning unused-function parisc/uapi: Use Kbuild logic to provide <asm/types.h> parisc: Make user stack size configurable parisc: Use _TIF_USER_WORK_MASK in entry.S parisc: Drop loops_per_jiffy from per_cpu struct
2020-12-15Merge branch 'exec-update-lock-for-v5.11' of ↵Linus Torvalds1-6/+6
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull exec-update-lock update from Eric Biederman: "The key point of this is to transform exec_update_mutex into a rw_semaphore so readers can be separated from writers. This makes it easier to understand what the holders of the lock are doing, and makes it harder to contend or deadlock on the lock. The real deadlock fix wound up in perf_event_open" * 'exec-update-lock-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: exec: Transform exec_update_mutex into a rw_semaphore
2020-12-15Merge branch 'exec-for-v5.11' of ↵Linus Torvalds1-21/+18
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull execve updates from Eric Biederman: "This set of changes ultimately fixes the interaction of posix file lock and exec. Fundamentally most of the change is just moving where unshare_files is called during exec, and tweaking the users of files_struct so that the count of files_struct is not unnecessarily played with. Along the way fcheck and related helpers were renamed to more accurately reflect what they do. There were also many other small changes that fell out, as this is the first time in a long time much of this code has been touched. Benchmarks haven't turned up any practical issues but Al Viro has observed a possibility for a lot of pounding on task_lock. So I have some changes in progress to convert put_files_struct to always rcu free files_struct. That wasn't ready for the merge window so that will have to wait until next time" * 'exec-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits) exec: Move io_uring_task_cancel after the point of no return coredump: Document coredump code exclusively used by cell spufs file: Remove get_files_struct file: Rename __close_fd_get_file close_fd_get_file file: Replace ksys_close with close_fd file: Rename __close_fd to close_fd and remove the files parameter file: Merge __alloc_fd into alloc_fd file: In f_dupfd read RLIMIT_NOFILE once. file: Merge __fd_install into fd_install proc/fd: In fdinfo seq_show don't use get_files_struct bpf/task_iter: In task_file_seq_get_next use task_lookup_next_fd_rcu proc/fd: In proc_readfd_common use task_lookup_next_fd_rcu file: Implement task_lookup_next_fd_rcu kcmp: In get_file_raw_ptr use task_lookup_fd_rcu proc/fd: In tid_fd_mode use task_lookup_fd_rcu file: Implement task_lookup_fd_rcu file: Rename fcheck lookup_fd_rcu file: Replace fcheck_files with files_lookup_fd_rcu file: Factor files_lookup_fd_locked out of fcheck_files file: Rename __fcheck_files to files_lookup_fd_raw ...
2020-12-10exec: Transform exec_update_mutex into a rw_semaphoreEric W. Biederman1-6/+6
Recently syzbot reported[0] that there is a deadlock amongst the users of exec_update_mutex. The problematic lock ordering found by lockdep was: perf_event_open (exec_update_mutex -> ovl_i_mutex) chown (ovl_i_mutex -> sb_writes) sendfile (sb_writes -> p->lock) by reading from a proc file and writing to overlayfs proc_pid_syscall (p->lock -> exec_update_mutex) While looking at possible solutions it occured to me that all of the users and possible users involved only wanted to state of the given process to remain the same. They are all readers. The only writer is exec. There is no reason for readers to block on each other. So fix this deadlock by transforming exec_update_mutex into a rw_semaphore named exec_update_lock that only exec takes for writing. Cc: Jann Horn <jannh@google.com> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Bernd Edlinger <bernd.edlinger@hotmail.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Christopher Yeoh <cyeoh@au1.ibm.com> Cc: Cyrill Gorcunov <gorcunov@gmail.com> Cc: Sargun Dhillon <sargun@sargun.me> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Fixes: eea9673250db ("exec: Add exec_update_mutex to replace cred_guard_mutex") [0] https://lkml.kernel.org/r/00000000000063640c05ade8e3de@google.com Reported-by: syzbot+db9cdf3dd1f64252c6ef@syzkaller.appspotmail.com Link: https://lkml.kernel.org/r/87ft4mbqen.fsf@x220.int.ebiederm.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-12-10exec: Move io_uring_task_cancel after the point of no returnEric W. Biederman1-5/+5
Now that unshare_files happens in begin_new_exec after the point of no return, io_uring_task_cancel can also happen later. Effectively this means io_uring activities for a task are only canceled when exec succeeds. Link: https://lkml.kernel.org/r/878saih2op.fsf@x220.int.ebiederm.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-12-10exec: Simplify unshare_filesEric W. Biederman1-4/+1
Now that exec no longer needs to return the unshared files to their previous value there is no reason to return displaced. Instead when unshare_fd creates a copy of the file table, call put_files_struct before returning from unshare_files. Acked-by: Christian Brauner <christian.brauner@ubuntu.com> v1: https://lkml.kernel.org/r/20200817220425.9389-2-ebiederm@xmission.com Link: https://lkml.kernel.org/r/20201120231441.29911-2-ebiederm@xmission.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-12-10exec: Move unshare_files to fix posix file locking during execEric W. Biederman1-14/+15
Many moons ago the binfmts were doing some very questionable things with file descriptors and an unsharing of the file descriptor table was added to make things better[1][2]. The helper steal_lockss was added to avoid breaking the userspace programs[3][4][6]. Unfortunately it turned out that steal_locks did not work for network file systems[5], so it was removed to see if anyone would complain[7][8]. It was thought at the time that NPTL would not be affected as the unshare_files happened after the other threads were killed[8]. Unfortunately because there was an unshare_files in binfmt_elf.c before the threads were killed this analysis was incorrect. This unshare_files in binfmt_elf.c resulted in the unshares_files happening whenever threads were present. Which led to unshare_files being moved to the start of do_execve[9]. Later the problems were rediscovered and the suggested approach was to readd steal_locks under a different name[10]. I happened to be reviewing patches and I noticed that this approach was a step backwards[11]. I proposed simply moving unshare_files[12] and it was pointed out that moving unshare_files without auditing the code was also unsafe[13]. There were then several attempts to solve this[14][15][16] and I even posted this set of changes[17]. Unfortunately because auditing all of execve is time consuming this change did not make it in at the time. Well now that I am cleaning up exec I have made the time to read through all of the binfmts and the only playing with file descriptors is either the security modules closing them in security_bprm_committing_creds or is in the generic code in fs/exec.c. None of it happens before begin_new_exec is called. So move unshare_files into begin_new_exec, after the point of no return. If memory is very very very low and the application calling exec is sharing file descriptor tables between processes we might fail past the point of no return. Which is unfortunate but no different than any of the other places where we allocate memory after the point of no return. This movement allows another process that shares the file table, or another thread of the same process and that closes files or changes their close on exec behavior and races with execve to cause some unexpected things to happen. There is only one time of check to time of use race and it is just there so that execve fails instead of an interpreter failing when it tries to open the file it is supposed to be interpreting. Failing later if userspace is being silly is not a problem. With this change it the following discription from the removal of steal_locks[8] finally becomes true. Apps using NPTL are not affected, since all other threads are killed before execve. Apps using LinuxThreads are only affected if they - have multiple threads during exec (LinuxThreads doesn't kill other threads, the app may do it with pthread_kill_other_threads_np()) - rely on POSIX locks being inherited across exec Both conditions are documented, but not their interaction. Apps using clone() natively are affected if they - use clone(CLONE_FILES) - rely on POSIX locks being inherited across exec I have investigated some paths to make it possible to solve this without moving unshare_files but they all look more complicated[18]. Reported-by: Daniel P. Berrangé <berrange@redhat.com> Reported-by: Jeff Layton <jlayton@redhat.com> History-tree: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git [1] 02cda956de0b ("[PATCH] unshare_files" [2] 04e9bcb4d106 ("[PATCH] use new unshare_files helper") [3] 088f5d7244de ("[PATCH] add steal_locks helper") [4] 02c541ec8ffa ("[PATCH] use new steal_locks helper") [5] https://lkml.kernel.org/r/E1FLIlF-0007zR-00@dorka.pomaz.szeredi.hu [6] https://lkml.kernel.org/r/0060321191605.GB15997@sorel.sous-sol.org [7] https://lkml.kernel.org/r/E1FLwjC-0000kJ-00@dorka.pomaz.szeredi.hu [8] c89681ed7d0e ("[PATCH] remove steal_locks()") [9] fd8328be874f ("[PATCH] sanitize handling of shared descriptor tables in failing execve()") [10] https://lkml.kernel.org/r/20180317142520.30520-1-jlayton@kernel.org [11] https://lkml.kernel.org/r/87r2nwqk73.fsf@xmission.com [12] https://lkml.kernel.org/r/87bmfgvg8w.fsf@xmission.com [13] https://lkml.kernel.org/r/20180322111424.GE30522@ZenIV.linux.org.uk [14] https://lkml.kernel.org/r/20180827174722.3723-1-jlayton@kernel.org [15] https://lkml.kernel.org/r/20180830172423.21964-1-jlayton@kernel.org [16] https://lkml.kernel.org/r/20180914105310.6454-1-jlayton@kernel.org [17] https://lkml.kernel.org/r/87a7ohs5ow.fsf@xmission.com [18] https://lkml.kernel.org/r/87pn8c1uj6.fsf_-_@x220.int.ebiederm.org Acked-by: Christian Brauner <christian.brauner@ubuntu.com> v1: https://lkml.kernel.org/r/20200817220425.9389-1-ebiederm@xmission.com Link: https://lkml.kernel.org/r/20201120231441.29911-1-ebiederm@xmission.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-12-10exec: Don't open code get_close_on_execEric W. Biederman1-2/+1
Al Viro pointed out that using the phrase "close_on_exec(fd, rcu_dereference_raw(current->files->fdt))" instead of wrapping it in rcu_read_lock(), rcu_read_unlock() is a very questionable optimization[1]. Once wrapped with rcu_read_lock()/rcu_read_unlock() that phrase becomes equivalent the helper function get_close_on_exec so simplify the code and make it more robust by simply using get_close_on_exec. [1] https://lkml.kernel.org/r/20201207222214.GA4115853@ZenIV.linux.org.uk Suggested-by: Al Viro <viro@ftp.linux.org.uk> Link: https://lkml.kernel.org/r/87k0tqr6zi.fsf_-_@x220.int.ebiederm.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-12-02kernel: Implement selective syscall userspace redirectionGabriel Krisman Bertazi1-0/+3
Introduce a mechanism to quickly disable/enable syscall handling for a specific process and redirect to userspace via SIGSYS. This is useful for processes with parts that require syscall redirection and parts that don't, but who need to perform this boundary crossing really fast, without paying the cost of a system call to reconfigure syscall handling on each boundary transition. This is particularly important for Windows games running over Wine. The proposed interface looks like this: prctl(PR_SET_SYSCALL_USER_DISPATCH, <op>, <off>, <length>, [selector]) The range [<offset>,<offset>+<length>) is a part of the process memory map that is allowed to by-pass the redirection code and dispatch syscalls directly, such that in fast paths a process doesn't need to disable the trap nor the kernel has to check the selector. This is essential to return from SIGSYS to a blocked area without triggering another SIGSYS from rt_sigreturn. selector is an optional pointer to a char-sized userspace memory region that has a key switch for the mechanism. This key switch is set to either PR_SYS_DISPATCH_ON, PR_SYS_DISPATCH_OFF to enable and disable the redirection without calling the kernel. The feature is meant to be set per-thread and it is disabled on fork/clone/execv. Internally, this doesn't add overhead to the syscall hot path, and it requires very little per-architecture support. I avoided using seccomp, even though it duplicates some functionality, due to previous feedback that maybe it shouldn't mix with seccomp since it is not a security mechanism. And obviously, this should never be considered a security mechanism, since any part of the program can by-pass it by using the syscall dispatcher. For the sysinfo benchmark, which measures the overhead added to executing a native syscall that doesn't require interception, the overhead using only the direct dispatcher region to issue syscalls is pretty much irrelevant. The overhead of using the selector goes around 40ns for a native (unredirected) syscall in my system, and it is (as expected) dominated by the supervisor-mode user-address access. In fact, with SMAP off, the overhead is consistently less than 5ns on my test box. Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20201127193238.821364-4-krisman@collabora.com
2020-11-11parisc: Make user stack size configurableHelge Deller1-2/+2
On parisc we need to initialize the memory layout for the user stack at process start time to a fixed size, which up until now was limited to the size as given by CONFIG_MAX_STACK_SIZE_MB at compile time. This hard limit was too small and showed problems when compiling ruby2.7, qmlcachegen and some Qt packages. This patch changes two things: a) It increases the default maximum stack size to 100MB. b) Users can modify the stack hard limit size with ulimit and then newly forked processes will use the given stack size which can even be bigger than the default 100MB. Reported-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de>
2020-10-16Merge tag 'powerpc-5.10-1' of ↵Linus Torvalds1-2/+15
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - A series from Nick adding ARCH_WANT_IRQS_OFF_ACTIVATE_MM & selecting it for powerpc, as well as a related fix for sparc. - Remove support for PowerPC 601. - Some fixes for watchpoints & addition of a new ptrace flag for detecting ISA v3.1 (Power10) watchpoint features. - A fix for kernels using 4K pages and the hash MMU on bare metal Power9 systems with > 16TB of RAM, or RAM on the 2nd node. - A basic idle driver for shallow stop states on Power10. - Tweaks to our sched domains code to better inform the scheduler about the hardware topology on Power9/10, where two SMT4 cores can be presented by firmware as an SMT8 core. - A series doing further reworks & cleanups of our EEH code. - Addition of a filter for RTAS (firmware) calls done via sys_rtas(), to prevent root from overwriting kernel memory. - Other smaller features, fixes & cleanups. Thanks to: Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Athira Rajeev, Biwen Li, Cameron Berkenpas, Cédric Le Goater, Christophe Leroy, Christoph Hellwig, Colin Ian King, Daniel Axtens, David Dai, Finn Thain, Frederic Barrat, Gautham R. Shenoy, Greg Kurz, Gustavo Romero, Ira Weiny, Jason Yan, Joel Stanley, Jordan Niethe, Kajol Jain, Konrad Rzeszutek Wilk, Laurent Dufour, Leonardo Bras, Liu Shixin, Luca Ceresoli, Madhavan Srinivasan, Mahesh Salgaonkar, Nathan Lynch, Nicholas Mc Guire, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Pedro Miraglia Franco de Carvalho, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Ravi Bangoria, Russell Currey, Satheesh Rajendran, Scott Cheloha, Segher Boessenkool, Srikar Dronamraju, Stan Johnson, Stephen Kitt, Stephen Rothwell, Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, Vasant Hegde, Wang Wensheng, Wolfram Sang, Yang Yingliang, zhengbin. * tag 'powerpc-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (228 commits) Revert "powerpc/pci: unmap legacy INTx interrupts when a PHB is removed" selftests/powerpc: Fix eeh-basic.sh exit codes cpufreq: powernv: Fix frame-size-overflow in powernv_cpufreq_reboot_notifier powerpc/time: Make get_tb() common to PPC32 and PPC64 powerpc/time: Make get_tbl() common to PPC32 and PPC64 powerpc/time: Remove get_tbu() powerpc/time: Avoid using get_tbl() and get_tbu() internally powerpc/time: Make mftb() common to PPC32 and PPC64 powerpc/time: Rename mftbl() to mftb() powerpc/32s: Remove #ifdef CONFIG_PPC_BOOK3S_32 in head_book3s_32.S powerpc/32s: Rename head_32.S to head_book3s_32.S powerpc/32s: Setup the early hash table at all time. powerpc/time: Remove ifdef in get_dec() and set_dec() powerpc: Remove get_tb_or_rtc() powerpc: Remove __USE_RTC() powerpc: Tidy up a bit after removal of PowerPC 601. powerpc: Remove support for PowerPC 601 powerpc: Remove PowerPC 601 powerpc: Drop SYNC_601() ISYNC_601() and SYNC() powerpc: Remove CONFIG_PPC601_SYNC_FIX ...
2020-10-15Merge tag 'char-misc-5.10-rc1' of ↵Linus Torvalds1-131/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big set of char, misc, and other assorted driver subsystem patches for 5.10-rc1. There's a lot of different things in here, all over the drivers/ directory. Some summaries: - soundwire driver updates - habanalabs driver updates - extcon driver updates - nitro_enclaves new driver - fsl-mc driver and core updates - mhi core and bus updates - nvmem driver updates - eeprom driver updates - binder driver updates and fixes - vbox minor bugfixes - fsi driver updates - w1 driver updates - coresight driver updates - interconnect driver updates - misc driver updates - other minor driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (396 commits) binder: fix UAF when releasing todo list docs: w1: w1_therm: Fix broken xref, mistakes, clarify text misc: Kconfig: fix a HISI_HIKEY_USB dependency LSM: Fix type of id parameter in kernel_post_load_data prototype misc: Kconfig: add a new dependency for HISI_HIKEY_USB firmware_loader: fix a kernel-doc markup w1: w1_therm: make w1_poll_completion static binder: simplify the return expression of binder_mmap test_firmware: Test partial read support firmware: Add request_partial_firmware_into_buf() firmware: Store opt_flags in fw_priv fs/kernel_file_read: Add "offset" arg for partial reads IMA: Add support for file reads without contents LSM: Add "contents" flag to kernel_read_file hook module: Call security_kernel_post_load_data() firmware_loader: Use security_post_load_data() LSM: Introduce kernel_post_load_data() hook fs/kernel_read_file: Add file_size output argument fs/kernel_read_file: Switch buffer size arg to size_t fs/kernel_read_file: Remove redundant size argument ...
2020-10-05fs/kernel_read_file: Split into separate source fileKees Cook1-132/+0
These routines are used in places outside of exec(2), so in preparation for refactoring them, move them into a separate source file, fs/kernel_read_file.c. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Scott Branden <scott.branden@broadcom.com> Link: https://lore.kernel.org/r/20201002173828.2099543-5-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05fs/kernel_read_file: Split into separate include fileScott Branden1-0/+1
Move kernel_read_file* out of linux/fs.h to its own linux/kernel_read_file.h include file. That header gets pulled in just about everywhere and doesn't really need functions not related to the general fs interface. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Scott Branden <scott.branden@broadcom.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: James Morris <jamorris@linux.microsoft.com> Link: https://lore.kernel.org/r/20200706232309.12010-2-scott.branden@broadcom.com Link: https://lore.kernel.org/r/20201002173828.2099543-4-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>