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2019-03-05Merge branch 'timers-2038-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull year 2038 updates from Thomas Gleixner: "Another round of changes to make the kernel ready for 2038. After lots of preparatory work this is the first set of syscalls which are 2038 safe: 403 clock_gettime64 404 clock_settime64 405 clock_adjtime64 406 clock_getres_time64 407 clock_nanosleep_time64 408 timer_gettime64 409 timer_settime64 410 timerfd_gettime64 411 timerfd_settime64 412 utimensat_time64 413 pselect6_time64 414 ppoll_time64 416 io_pgetevents_time64 417 recvmmsg_time64 418 mq_timedsend_time64 419 mq_timedreceiv_time64 420 semtimedop_time64 421 rt_sigtimedwait_time64 422 futex_time64 423 sched_rr_get_interval_time64 The syscall numbers are identical all over the architectures" * 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) riscv: Use latest system call ABI checksyscalls: fix up mq_timedreceive and stat exceptions unicore32: Fix __ARCH_WANT_STAT64 definition asm-generic: Make time32 syscall numbers optional asm-generic: Drop getrlimit and setrlimit syscalls from default list 32-bit userspace ABI: introduce ARCH_32BIT_OFF_T config option compat ABI: use non-compat openat and open_by_handle_at variants y2038: add 64-bit time_t syscalls to all 32-bit architectures y2038: rename old time and utime syscalls y2038: remove struct definition redirects y2038: use time32 syscall names on 32-bit syscalls: remove obsolete __IGNORE_ macros y2038: syscalls: rename y2038 compat syscalls x86/x32: use time64 versions of sigtimedwait and recvmmsg timex: change syscalls to use struct __kernel_timex timex: use __kernel_timex internally sparc64: add custom adjtimex/clock_adjtime functions time: fix sys_timer_settime prototype time: Add struct __kernel_timex time: make adjtime compat handling available for 32 bit ...
2019-02-13signal: Restore the stop PTRACE_EVENT_EXITEric W. Biederman1-2/+5
In the middle of do_exit() there is there is a call "ptrace_event(PTRACE_EVENT_EXIT, code);" That call places the process in TACKED_TRACED aka "(TASK_WAKEKILL | __TASK_TRACED)" and waits for for the debugger to release the task or SIGKILL to be delivered. Skipping past dequeue_signal when we know a fatal signal has already been delivered resulted in SIGKILL remaining pending and TIF_SIGPENDING remaining set. This in turn caused the scheduler to not sleep in PTACE_EVENT_EXIT as it figured a fatal signal was pending. This also caused ptrace_freeze_traced in ptrace_check_attach to fail because it left a per thread SIGKILL pending which is what fatal_signal_pending tests for. This difference in signal state caused strace to report strace: Exit of unknown pid NNNNN ignored Therefore update the signal handling state like dequeue_signal would when removing a per thread SIGKILL, by removing SIGKILL from the per thread signal mask and clearing TIF_SIGPENDING. Acked-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Ivan Delalande <colona@arista.com> Cc: stable@vger.kernel.org Fixes: 35634ffa1751 ("signal: Always notice exiting tasks") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-02-07signal: Better detection of synchronous signalsEric W. Biederman1-1/+51
Recently syzkaller was able to create unkillablle processes by creating a timer that is delivered as a thread local signal on SIGHUP, and receiving SIGHUP SA_NODEFERER. Ultimately causing a loop failing to deliver SIGHUP but always trying. When the stack overflows delivery of SIGHUP fails and force_sigsegv is called. Unfortunately because SIGSEGV is numerically higher than SIGHUP next_signal tries again to deliver a SIGHUP. From a quality of implementation standpoint attempting to deliver the timer SIGHUP signal is wrong. We should attempt to deliver the synchronous SIGSEGV signal we just forced. We can make that happening in a fairly straight forward manner by instead of just looking at the signal number we also look at the si_code. In particular for exceptions (aka synchronous signals) the si_code is always greater than 0. That still has the potential to pick up a number of asynchronous signals as in a few cases the same si_codes that are used for synchronous signals are also used for asynchronous signals, and SI_KERNEL is also included in the list of possible si_codes. Still the heuristic is much better and timer signals are definitely excluded. Which is enough to prevent all known ways for someone sending a process signals fast enough to cause unexpected and arguably incorrect behavior. Cc: stable@vger.kernel.org Fixes: a27341cd5fcb ("Prioritize synchronous signals over 'normal' signals") Tested-by: Dmitry Vyukov <dvyukov@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-02-07signal: Always notice exiting tasksEric W. Biederman1-0/+6
Recently syzkaller was able to create unkillablle processes by creating a timer that is delivered as a thread local signal on SIGHUP, and receiving SIGHUP SA_NODEFERER. Ultimately causing a loop failing to deliver SIGHUP but always trying. Upon examination it turns out part of the problem is actually most of the solution. Since 2.5 signal delivery has found all fatal signals, marked the signal group for death, and queued SIGKILL in every threads thread queue relying on signal->group_exit_code to preserve the information of which was the actual fatal signal. The conversion of all fatal signals to SIGKILL results in the synchronous signal heuristic in next_signal kicking in and preferring SIGHUP to SIGKILL. Which is especially problematic as all fatal signals have already been transformed into SIGKILL. Instead of dequeueing signals and depending upon SIGKILL to be the first signal dequeued, first test if the signal group has already been marked for death. This guarantees that nothing in the signal queue can prevent a process that needs to exit from exiting. Cc: stable@vger.kernel.org Tested-by: Dmitry Vyukov <dvyukov@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Ref: ebf5ebe31d2c ("[PATCH] signal-fixes-2.5.59-A4") History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-02-07y2038: syscalls: rename y2038 compat syscallsArnd Bergmann1-1/+1
A lot of system calls that pass a time_t somewhere have an implementation using a COMPAT_SYSCALL_DEFINEx() on 64-bit architectures, and have been reworked so that this implementation can now be used on 32-bit architectures as well. The missing step is to redefine them using the regular SYSCALL_DEFINEx() to get them out of the compat namespace and make it possible to build them on 32-bit architectures. Any system call that ends in 'time' gets a '32' suffix on its name for that version, while the others get a '_time32' suffix, to distinguish them from the normal version, which takes a 64-bit time argument in the future. In this step, only 64-bit architectures are changed, doing this rename first lets us avoid touching the 32-bit architectures twice. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-02-05signal: Always attempt to allocate siginfo for SIGSTOPEric W. Biederman1-3/+2
Since 2.5.34 the code has had the potential to not allocate siginfo for SIGSTOP signals. Except for ptrace this is perfectly fine as only ptrace can use PTRACE_PEEK_SIGINFO and see what the contents of the delivered siginfo are. Users of PTRACE_PEEK_SIGINFO that care about the contents siginfo for SIGSTOP are rare, but they do exist. A seccomp self test has cared and lldb cares. Jack Andersen <jackoalan@gmail.com> writes: > The patch titled > `signal: Never allocate siginfo for SIGKILL or SIGSTOP` > created a regression for users of PTRACE_GETSIGINFO needing to > discern signals that were raised via the tgkill syscall. > > A notable user of this tgkill+ptrace combination is lldb while > debugging a multithreaded program. Without the ability to detect a > SIGSTOP originating from tgkill, lldb does not have a way to > synchronize on a per-thread basis and falls back to SIGSTOP-ing the > entire process. Everyone affected by this please note. The kernel can still fail to allocate a siginfo structure. The allocation is with GFP_KERNEL and is best effort only. If memory is tight when the signal allocation comes in this will fail to allocate a siginfo. So I strongly recommend looking at more robust solutions for synchronizing with a single thread such as PTRACE_INTERRUPT. Or if that does not work persuading your friendly local kernel developer to build the interface you need. Reported-by: Tycho Andersen <tycho@tycho.ws> Reported-by: Kees Cook <keescook@chromium.org> Reported-by: Jack Andersen <jackoalan@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Christian Brauner <christian@brauner.io> Cc: stable@vger.kernel.org Fixes: f149b3155744 ("signal: Never allocate siginfo for SIGKILL or SIGSTOP") Fixes: 6dfc88977e42 ("[PATCH] shared thread signals") History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-01-03Remove 'type' argument from access_ok() functionLinus Torvalds1-4/+4
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-18y2038: signal: Add compat_sys_rt_sigtimedwait_time64Arnd Bergmann1-0/+32
Now that 32-bit architectures have two variants of sys_rt_sigtimedwaid() for 32-bit and 64-bit time_t, we also need to have a second compat system call entry point on the corresponding 64-bit architectures. The traditional system call keeps getting handled by compat_sys_rt_sigtimedwait(), and this adds a new compat_sys_rt_sigtimedwait_time64() that differs only in the timeout argument type. The naming remains a bit asymmetric for the moment. Ideally we would want to have compat_sys_rt_sigtimedwait_time32() for the old version and compat_sys_rt_sigtimedwait() for the new one to mirror the names of the native entry points, but renaming the existing system call tables causes unnecessary churn. I would suggest renaming all such system calls together at a later point. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-18y2038: signal: Add sys_rt_sigtimedwait_time32Arnd Bergmann1-0/+33
Once sys_rt_sigtimedwait() gets changed to a 64-bit time_t, we have to provide compatibility support for existing binaries. An earlier version of this patch reused the compat_sys_rt_sigtimedwait entry point to avoid code duplication, but this newer approach duplicates the existing native entry point instead, which seems a bit cleaner. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06signal: Add restore_user_sigmask()Deepa Dinamani1-0/+33
Refactor the logic to restore the sigmask before the syscall returns into an api. This is useful for versions of syscalls that pass in the sigmask and expect the current->sigmask to be changed during the execution and restored after the execution of the syscall. With the advent of new y2038 syscalls in the subsequent patches, we add two more new versions of the syscalls (for pselect, ppoll and io_pgetevents) in addition to the existing native and compat versions. Adding such an api reduces the logic that would need to be replicated otherwise. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06signal: Add set_user_sigmask()Deepa Dinamani1-0/+45
Refactor reading sigset from userspace and updating sigmask into an api. This is useful for versions of syscalls that pass in the sigmask and expect the current->sigmask to be changed during, and restored after, the execution of the syscall. With the advent of new y2038 syscalls in the subsequent patches, we add two more new versions of the syscalls (for pselect, ppoll, and io_pgetevents) in addition to the existing native and compat versions. Adding such an api reduces the logic that would need to be replicated otherwise. Note that the calls to sigprocmask() ignored the return value from the api as the function only returns an error on an invalid first argument that is hardcoded at these call sites. The updated logic uses set_current_blocked() instead. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-10-31kernel/signal.c: fix a comment errorWeikang Shi1-1/+1
Because get_signal_to_deliver() was renamed to get_signal() the comment should be fixed. Link: http://lkml.kernel.org/r/1539179128-45709-1-git-send-email-swkhack@gmail.com Signed-off-by: Weikang Shi <swkhack@gmail.com> Reported-by: Christian Brauner <christian@brauner.io> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-25Merge branch 'timers-core-for-linus' of ↵Linus Torvalds1-9/+10
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timekeeping updates from Thomas Gleixner: "The timers and timekeeping departement provides: - Another large y2038 update with further preparations for providing the y2038 safe timespecs closer to the syscalls. - An overhaul of the SHCMT clocksource driver - SPDX license identifier updates - Small cleanups and fixes all over the place" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits) tick/sched : Remove redundant cpu_online() check clocksource/drivers/dw_apb: Add reset control clocksource: Remove obsolete CLOCKSOURCE_OF_DECLARE clocksource/drivers: Unify the names to timer-* format clocksource/drivers/sh_cmt: Add R-Car gen3 support dt-bindings: timer: renesas: cmt: document R-Car gen3 support clocksource/drivers/sh_cmt: Properly line-wrap sh_cmt_of_table[] initializer clocksource/drivers/sh_cmt: Fix clocksource width for 32-bit machines clocksource/drivers/sh_cmt: Fixup for 64-bit machines clocksource/drivers/sh_tmu: Convert to SPDX identifiers clocksource/drivers/sh_mtu2: Convert to SPDX identifiers clocksource/drivers/sh_cmt: Convert to SPDX identifiers clocksource/drivers/renesas-ostm: Convert to SPDX identifiers clocksource: Convert to using %pOFn instead of device_node.name tick/broadcast: Remove redundant check RISC-V: Request newstat syscalls y2038: signal: Change rt_sigtimedwait to use __kernel_timespec y2038: socket: Change recvmmsg to use __kernel_timespec y2038: sched: Change sched_rr_get_interval to use __kernel_timespec y2038: utimes: Rework #ifdef guards for compat syscalls ...
2018-10-24Merge branch 'siginfo-linus' of ↵Linus Torvalds1-149/+272
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull siginfo updates from Eric Biederman: "I have been slowly sorting out siginfo and this is the culmination of that work. The primary result is in several ways the signal infrastructure has been made less error prone. The code has been updated so that manually specifying SEND_SIG_FORCED is never necessary. The conversion to the new siginfo sending functions is now complete, which makes it difficult to send a signal without filling in the proper siginfo fields. At the tail end of the patchset comes the optimization of decreasing the size of struct siginfo in the kernel from 128 bytes to about 48 bytes on 64bit. The fundamental observation that enables this is by definition none of the known ways to use struct siginfo uses the extra bytes. This comes at the cost of a small user space observable difference. For the rare case of siginfo being injected into the kernel only what can be copied into kernel_siginfo is delivered to the destination, the rest of the bytes are set to 0. For cases where the signal and the si_code are known this is safe, because we know those bytes are not used. For cases where the signal and si_code combination is unknown the bits that won't fit into struct kernel_siginfo are tested to verify they are zero, and the send fails if they are not. I made an extensive search through userspace code and I could not find anything that would break because of the above change. If it turns out I did break something it will take just the revert of a single change to restore kernel_siginfo to the same size as userspace siginfo. Testing did reveal dependencies on preferring the signo passed to sigqueueinfo over si->signo, so bit the bullet and added the complexity necessary to handle that case. Testing also revealed bad things can happen if a negative signal number is passed into the system calls. Something no sane application will do but something a malicious program or a fuzzer might do. So I have fixed the code that performs the bounds checks to ensure negative signal numbers are handled" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (80 commits) signal: Guard against negative signal numbers in copy_siginfo_from_user32 signal: Guard against negative signal numbers in copy_siginfo_from_user signal: In sigqueueinfo prefer sig not si_signo signal: Use a smaller struct siginfo in the kernel signal: Distinguish between kernel_siginfo and siginfo signal: Introduce copy_siginfo_from_user and use it's return value signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZE signal: Fail sigqueueinfo if si_signo != sig signal/sparc: Move EMT_TAGOVF into the generic siginfo.h signal/unicore32: Use force_sig_fault where appropriate signal/unicore32: Generate siginfo in ucs32_notify_die signal/unicore32: Use send_sig_fault where appropriate signal/arc: Use force_sig_fault where appropriate signal/arc: Push siginfo generation into unhandled_exception signal/ia64: Use force_sig_fault where appropriate signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn signal/ia64: Use the generic force_sigsegv in setup_frame signal/arm/kvm: Use send_sig_mceerr signal/arm: Use send_sig_fault where appropriate signal/arm: Use force_sig_fault where appropriate ...
2018-10-10signal: Guard against negative signal numbers in copy_siginfo_from_user32Eric W. Biederman1-1/+1
While fixing an out of bounds array access in known_siginfo_layout reported by the kernel test robot it became apparent that the same bug exists in siginfo_layout and affects copy_siginfo_from_user32. The straight forward fix that makes guards against making this mistake in the future and should keep the code size small is to just take an unsigned signal number instead of a signed signal number, as I did to fix known_siginfo_layout. Cc: stable@vger.kernel.org Fixes: cc731525f26a ("signal: Remove kernel interal si_code magic") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-10signal: Guard against negative signal numbers in copy_siginfo_from_userEric W. Biederman1-1/+1
The bounds checks in known_siginfo_layout only guards against positive numbers that are too large, large negative can slip through and can cause out of bounds accesses. Ordinarily this is not a concern because early in signal processing the signal number is filtered with valid_signal which ensures it is a small positive signal number, but copy_siginfo_from_user is called before this check is performed. [ 73.031126] BUG: unable to handle kernel paging request at ffffffff6281bcb6 [ 73.032038] PGD 3014067 P4D 3014067 PUD 0 [ 73.032565] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI [ 73.033287] CPU: 0 PID: 732 Comm: trinity-c3 Tainted: G W T 4.19.0-rc1-00077-g4ce5f9c #1 [ 73.034423] RIP: 0010:copy_siginfo_from_user+0x4d/0xd0 [ 73.034908] Code: 00 8b 53 08 81 fa 80 00 00 00 0f 84 90 00 00 00 85 d2 7e 2d 48 63 0b 83 f9 1f 7f 1c 8d 71 ff bf d8 04 01 50 48 0f a3 f7 73 0e <0f> b6 8c 09 20 bb 81 82 39 ca 7f 15 eb 68 31 c0 83 fa 06 7f 0c eb [ 73.036665] RSP: 0018:ffff88001b8f7e20 EFLAGS: 00010297 [ 73.037160] RAX: 0000000000000000 RBX: ffff88001b8f7e90 RCX: fffffffff00000cb [ 73.037865] RDX: 0000000000000001 RSI: 00000000f00000ca RDI: 00000000500104d8 [ 73.038546] RBP: ffff88001b8f7e80 R08: 0000000000000000 R09: 0000000000000000 [ 73.039201] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000008 [ 73.039874] R13: 00000000000002dc R14: 0000000000000000 R15: 0000000000000000 [ 73.040613] FS: 000000000104a880(0000) GS:ffff88001f000000(0000) knlGS:0000000000000000 [ 73.041649] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 73.042405] CR2: ffffffff6281bcb6 CR3: 000000001cb52003 CR4: 00000000001606b0 [ 73.043351] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 73.044286] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 [ 73.045221] Call Trace: [ 73.045556] __x64_sys_rt_tgsigqueueinfo+0x34/0xa0 [ 73.046199] do_syscall_64+0x1a4/0x390 [ 73.046708] ? vtime_user_enter+0x61/0x80 [ 73.047242] ? __context_tracking_enter+0x4e/0x60 [ 73.047714] ? __context_tracking_enter+0x4e/0x60 [ 73.048278] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Therefore fix known_siginfo_layout to take an unsigned signal number instead of a signed signal number. All valid signal numbers are small positive numbers so they will not be affected, but invalid negative signal numbers will now become large positive signal numbers and will not be used as indices into the sig_sicodes array. Making the signal number unsigned makes it difficult for similar mistakes to happen in the future. Fixes: 4ce5f9c9e754 ("signal: Use a smaller struct siginfo in the kernel") Inspired-by: Sean Christopherson <sean.j.christopherson@intel.com> Reported-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-08signal: In sigqueueinfo prefer sig not si_signoEric W. Biederman1-57/+84
Andrei Vagin <avagin@gmail.com> reported: > Accoding to the man page, the user should not set si_signo, it has to be set > by kernel. > > $ man 2 rt_sigqueueinfo > > The uinfo argument specifies the data to accompany the signal. This > argument is a pointer to a structure of type siginfo_t, described in > sigaction(2) (and defined by including <sigaction.h>). The caller > should set the following fields in this structure: > > si_code > This must be one of the SI_* codes in the Linux kernel source > file include/asm-generic/siginfo.h, with the restriction that > the code must be negative (i.e., cannot be SI_USER, which is > used by the kernel to indicate a signal sent by kill(2)) and > cannot (since Linux 2.6.39) be SI_TKILL (which is used by the > kernel to indicate a signal sent using tgkill(2)). > > si_pid This should be set to a process ID, typically the process ID of > the sender. > > si_uid This should be set to a user ID, typically the real user ID of > the sender. > > si_value > This field contains the user data to accompany the signal. For > more information, see the description of the last (union sigval) > argument of sigqueue(3). > > Internally, the kernel sets the si_signo field to the value specified > in sig, so that the receiver of the signal can also obtain the signal > number via that field. > > On Tue, Sep 25, 2018 at 07:19:02PM +0200, Eric W. Biederman wrote: >> >> If there is some application that calls sigqueueinfo directly that has >> a problem with this added sanity check we can revisit this when we see >> what kind of crazy that application is doing. > > > I already know two "applications" ;) > > https://github.com/torvalds/linux/blob/master/tools/testing/selftests/ptrace/peeksiginfo.c > https://github.com/checkpoint-restore/criu/blob/master/test/zdtm/static/sigpending.c > > Disclaimer: I'm the author of both of them. Looking at the kernel code the historical behavior has alwasy been to prefer the signal number passed in by the kernel. So sigh. Implmenet __copy_siginfo_from_user and __copy_siginfo_from_user32 to take that signal number and prefer it. The user of ptrace will still use copy_siginfo_from_user and copy_siginfo_from_user32 as they do not and never have had a signal number there. Luckily this change has never made it farther than linux-next. Fixes: e75dc036c445 ("signal: Fail sigqueueinfo if si_signo != sig") Reported-by: Andrei Vagin <avagin@gmail.com> Tested-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03signal: Use a smaller struct siginfo in the kernelEric W. Biederman1-18/+64
We reserve 128 bytes for struct siginfo but only use about 48 bytes on 64bit and 32 bytes on 32bit. Someday we might use more but it is unlikely to be anytime soon. Userspace seems content with just enough bytes of siginfo to implement sigqueue. Or in the case of checkpoint/restart reinjecting signals the kernel has sent. Reducing the stack footprint and the work to copy siginfo around from 2 cachelines to 1 cachelines seems worth doing even if I don't have benchmarks to show a performance difference. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03signal: Distinguish between kernel_siginfo and siginfoEric W. Biederman1-52/+99
Linus recently observed that if we did not worry about the padding member in struct siginfo it is only about 48 bytes, and 48 bytes is much nicer than 128 bytes for allocating on the stack and copying around in the kernel. The obvious thing of only adding the padding when userspace is including siginfo.h won't work as there are sigframe definitions in the kernel that embed struct siginfo. So split siginfo in two; kernel_siginfo and siginfo. Keeping the traditional name for the userspace definition. While the version that is used internally to the kernel and ultimately will not be padded to 128 bytes is called kernel_siginfo. The definition of struct kernel_siginfo I have put in include/signal_types.h A set of buildtime checks has been added to verify the two structures have the same field offsets. To make it easy to verify the change kernel_siginfo retains the same size as siginfo. The reduction in size comes in a following change. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03signal: Introduce copy_siginfo_from_user and use it's return valueEric W. Biederman1-9/+16
In preparation for using a smaller version of siginfo in the kernel introduce copy_siginfo_from_user and use it when siginfo is copied from userspace. Make the pattern for using copy_siginfo_from_user and copy_siginfo_from_user32 to capture the return value and return that value on error. This is a necessary prerequisite for using a smaller siginfo in the kernel than the kernel exports to userspace. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZEEric W. Biederman1-3/+0
Rework the defintion of struct siginfo so that the array padding struct siginfo to SI_MAX_SIZE can be placed in a union along side of the rest of the struct siginfo members. The result is that we no longer need the __ARCH_SI_PREAMBLE_SIZE or SI_PAD_SIZE definitions. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03signal: Fail sigqueueinfo if si_signo != sigEric W. Biederman1-2/+4
The kernel needs to validate that the contents of struct siginfo make sense as siginfo is copied into the kernel, so that the proper union members can be put in the appropriate locations. The field si_signo is a fundamental part of that validation. As such changing the contents of si_signo after the validation make no sense and can result in nonsense values in the kernel. As such simply fail if someone is silly enough to set si_signo out of sync with the signal number passed to sigqueueinfo. I don't expect a problem as glibc's sigqueue implementation sets "si_signo = sig" and CRIU just returns to the kernel what the kernel gave to it. If there is some application that calls sigqueueinfo directly that has a problem with this added sanity check we can revisit this when we see what kind of crazy that application is doing. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03signal/sparc: Move EMT_TAGOVF into the generic siginfo.hEric W. Biederman1-1/+1
When moving all of the architectures specific si_codes into siginfo.h, I apparently overlooked EMT_TAGOVF. Move it now. Remove the now redundant test in siginfo_layout for SIGEMT as now NSIGEMT is always defined. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-01signal: Introduce COMPAT_SIGMINSTKSZ for use in compat_sys_sigaltstackWill Deacon1-5/+9
The sigaltstack(2) system call fails with -ENOMEM if the new alternative signal stack is found to be smaller than SIGMINSTKSZ. On architectures such as arm64, where the native value for SIGMINSTKSZ is larger than the compat value, this can result in an unexpected error being reported to a compat task. See, for example: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=904385 This patch fixes the problem by extending do_sigaltstack to take the minimum signal stack size as an additional parameter, allowing the native and compat system call entry code to pass in their respective values. COMPAT_SIGMINSTKSZ is just defined as SIGMINSTKSZ if it has not been defined by the architecture. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Oleg Nesterov <oleg@redhat.com> Reported-by: Steve McIntyre <steve.mcintyre@arm.com> Tested-by: Steve McIntyre <93sam@debian.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-16signal: Pair exports with their functionsEric W. Biederman1-8/+7
For readability and consistency with the other exports in kernel/signal.c pair the exports of signal sending functions with their functions, instead of having the exports in one big clump. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-16signal: Remove specific_send_sig_infoEric W. Biederman1-8/+2
This function is static and it only has two callers. As specific_send_sig_info is only called twice remembering what specific_send_sig_info does when reading the code is difficutl and it makes it hard to see which sending sending functions are equivalent to which others. So remove specific_send_sig_info to make the code easier to read. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-11signal: Remove SEND_SIG_FORCEDEric W. Biederman1-4/+3
There are no more users of SEND_SIG_FORCED so it may be safely removed. Remove the definition of SEND_SIG_FORCED, it's use in is_si_special, it's use in TP_STORE_SIGINFO, and it's use in __send_signal as without any users the uses of SEND_SIG_FORCED are now unncessary. This makes the code simpler, easier to understand and use. Users of signal sending functions now no longer need to ask themselves do I need to use SEND_SIG_FORCED. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-11signal: Never allocate siginfo for SIGKILL or SIGSTOPEric W. Biederman1-3/+4
The SIGKILL and SIGSTOP signals are never delivered to userspace so queued siginfo for these signals can never be observed. Therefore remove the chance of failure by never even attempting to allocate siginfo in those cases. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-11signal: Don't send siginfo to kthreads.Eric W. Biederman1-1/+1
Today kernel threads never dequeue siginfo so it is pointless to enqueue siginfo for them. The usb gadget mass storage driver goes one farther and uses SEND_SIG_FORCED to guarantee that no siginfo is even enqueued. Generalize the optimization of the usb mass storage driver and never perform an unnecessary allocation when delivering signals to kthreads. Switch the mass storage driver from sending signals with SEND_SIG_FORCED to SEND_SIG_PRIV. As using SEND_SIG_FORCED is now unnecessary. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-11signal: Always deliver the kernel's SIGKILL and SIGSTOP to a pid namespace initEric W. Biederman1-1/+1
Instead of playing whack-a-mole and changing SEND_SIG_PRIV to SEND_SIG_FORCED throughout the kernel to ensure a pid namespace init gets signals sent by the kernel, stop allowing a pid namespace init to ignore SIGKILL or SIGSTOP sent by the kernel. A pid namespace init is only supposed to be able to ignore signals sent from itself and children with SIG_DFL. Fixes: 921cf9f63089 ("signals: protect cinit from unblocked SIG_DFL signals") Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-11signal: Always ignore SIGKILL and SIGSTOP sent to the global initEric W. Biederman1-0/+4
If the first process started (aka /sbin/init) receives a SIGKILL it will panic the system if it is delivered. Making the system unusable and undebugable. It isn't much better if the first process started receives SIGSTOP. So always ignore SIGSTOP and SIGKILL sent to init. This is done in a separate clause in sig_task_ignored as force_sig_info can clear SIG_UNKILLABLE and this protection should work even then. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-08-29y2038: signal: Change rt_sigtimedwait to use __kernel_timespecArnd Bergmann1-8/+9
This changes sys_rt_sigtimedwait() to use get_timespec64(), changing the timeout type to __kernel_timespec, which will be changed to use a 64-bit time_t in the future. Since the do_sigtimedwait() core function changes, we also have to modify the compat version of this system call in the same way. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-08-27y2038: globally rename compat_time to old_time32Arnd Bergmann1-1/+1
Christoph Hellwig suggested a slightly different path for handling backwards compatibility with the 32-bit time_t based system calls: Rather than simply reusing the compat_sys_* entry points on 32-bit architectures unchanged, we get rid of those entry points and the compat_time types by renaming them to something that makes more sense on 32-bit architectures (which don't have a compat mode otherwise), and then share the entry points under the new name with the 64-bit architectures that use them for implementing the compatibility. The following types and interfaces are renamed here, and moved from linux/compat_time.h to linux/time32.h: old new --- --- compat_time_t old_time32_t struct compat_timeval struct old_timeval32 struct compat_timespec struct old_timespec32 struct compat_itimerspec struct old_itimerspec32 ns_to_compat_timeval() ns_to_old_timeval32() get_compat_itimerspec64() get_old_itimerspec32() put_compat_itimerspec64() put_old_itimerspec32() compat_get_timespec64() get_old_timespec32() compat_put_timespec64() put_old_timespec32() As we already have aliases in place, this patch addresses only the instances that are relevant to the system call interface in particular, not those that occur in device drivers and other modules. Those will get handled separately, while providing the 64-bit version of the respective interfaces. I'm not renaming the timex, rusage and itimerval structures, as we are still debating what the new interface will look like, and whether we will need a replacement at all. This also doesn't change the names of the syscall entry points, which can be done more easily when we actually switch over the 32-bit architectures to use them, at that point we need to change COMPAT_SYSCALL_DEFINEx to SYSCALL_DEFINEx with a new name, e.g. with a _time32 suffix. Suggested-by: Christoph Hellwig <hch@infradead.org> Link: https://lore.kernel.org/lkml/20180705222110.GA5698@infradead.org/ Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-08-22Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-87/+83
Merge more updates from Andrew Morton: - the rest of MM - procfs updates - various misc things - more y2038 fixes - get_maintainer updates - lib/ updates - checkpatch updates - various epoll updates - autofs updates - hfsplus - some reiserfs work - fatfs updates - signal.c cleanups - ipc/ updates * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (166 commits) ipc/util.c: update return value of ipc_getref from int to bool ipc/util.c: further variable name cleanups ipc: simplify ipc initialization ipc: get rid of ids->tables_initialized hack lib/rhashtable: guarantee initial hashtable allocation lib/rhashtable: simplify bucket_table_alloc() ipc: drop ipc_lock() ipc/util.c: correct comment in ipc_obtain_object_check ipc: rename ipcctl_pre_down_nolock() ipc/util.c: use ipc_rcu_putref() for failues in ipc_addid() ipc: reorganize initialization of kern_ipc_perm.seq ipc: compute kern_ipc_perm.id under the ipc lock init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp adfs: use timespec64 for time conversion kernel/sysctl.c: fix typos in comments drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md fork: don't copy inconsistent signal handler state to child signal: make get_signal() return bool signal: make sigkill_pending() return bool ...
2018-08-22signal: make get_signal() return boolChristian Brauner1-2/+2
make get_signal() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-18-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make sigkill_pending() return boolChristian Brauner1-3/+3
sigkill_pending() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-17-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make legacy_queue() return boolChristian Brauner1-1/+1
legacy_queue() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-16-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make wants_signal() return boolChristian Brauner1-5/+9
wants_signal() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-15-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make flush_sigqueue_mask() voidChristian Brauner1-3/+2
The return value of flush_sigqueue_mask() is never checked anywhere. Link: http://lkml.kernel.org/r/20180602103653.18181-14-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make unhandled_signal() return boolChristian Brauner1-3/+5
unhandled_signal() already behaves like a boolean function. Let's actually declare it as such too. All callers treat it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-13-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make recalc_sigpending_tsk() return boolChristian Brauner1-3/+4
recalc_sigpending_tsk() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-12-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make has_pending_signals() return boolChristian Brauner1-1/+1
has_pending_signals() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-11-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make sig_ignored() return boolChristian Brauner1-3/+3
sig_ignored() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-10-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make sig_task_ignored() return boolChristian Brauner1-2/+2
sig_task_ignored() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-9-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make sig_handler_ignored() return boolChristian Brauner1-2/+2
sig_handler_ignored() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-8-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make kill_ok_by_cred() return boolChristian Brauner1-11/+6
kill_ok_by_cred() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-7-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: simplify rt_sigaction()Christian Brauner1-12/+10
The goto is not needed and does not add any clarity. Simply return -EINVAL on unexpected sigset_t struct size directly. Link: http://lkml.kernel.org/r/20180602103653.18181-6-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Acked-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make do_sigpending() voidChristian Brauner1-21/+20
do_sigpending() returned 0 unconditionally so it doesn't make sense to have it return at all. This allows us to simplify a bunch of syscall callers. Link: http://lkml.kernel.org/r/20180602103653.18181-5-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make may_ptrace_stop() return boolChristian Brauner1-4/+4
may_ptrace_stop() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-4-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22signal: make kill_as_cred_perm() return boolChristian Brauner1-6/+7
kill_as_cred_perm() already behaves like a boolean function. Let's actually declare it as such too. Link: http://lkml.kernel.org/r/20180602103653.18181-3-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Morris <james.morris@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>