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2021-09-30kprobes: treewide: Make it harder to refer kretprobe_trampoline directlyMasami Hiramatsu1-1/+1
Since now there is kretprobe_trampoline_addr() for referring the address of kretprobe trampoline code, we don't need to access kretprobe_trampoline directly. Make it harder to refer by renaming it to __kretprobe_trampoline(). Link: https://lkml.kernel.org/r/163163045446.489837.14510577516938803097.stgit@devnote2 Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: treewide: Remove trampoline_address from kretprobe_trampoline_handler()Masami Hiramatsu1-2/+1
The __kretprobe_trampoline_handler() callback, called from low level arch kprobes methods, has the 'trampoline_address' parameter, which is entirely superfluous as it basically just replicates: dereference_kernel_function_descriptor(kretprobe_trampoline) In fact we had bugs in arch code where it wasn't replicated correctly. So remove this superfluous parameter and use kretprobe_trampoline_addr() instead. Link: https://lkml.kernel.org/r/163163044546.489837.13505751885476015002.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: treewide: Replace arch_deref_entry_point() with ↵Masami Hiramatsu1-6/+1
dereference_symbol_descriptor() ~15 years ago kprobes grew the 'arch_deref_entry_point()' __weak function: 3d7e33825d87: ("jprobes: make jprobes a little safer for users") But this is just open-coded dereference_symbol_descriptor() in essence, and its obscure nature was causing bugs. Just use the real thing and remove arch_deref_entry_point(). Link: https://lkml.kernel.org/r/163163043630.489837.7924988885652708696.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: Use bool type for functions which returns boolean valueMasami Hiramatsu2-14/+14
Use the 'bool' type instead of 'int' for the functions which returns a boolean value, because this makes clear that those functions don't return any error code. Link: https://lkml.kernel.org/r/163163041649.489837.17311187321419747536.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: treewide: Use 'kprobe_opcode_t *' for the code address in ↵Masami Hiramatsu1-5/+5
get_optimized_kprobe() Since get_optimized_kprobe() is only used inside kprobes, it doesn't need to use 'unsigned long' type for 'addr' parameter. Make it use 'kprobe_opcode_t *' for the 'addr' parameter and subsequent call of arch_within_optimized_kprobe() also should use 'kprobe_opcode_t *'. Note that MAX_OPTIMIZED_LENGTH and RELATIVEJUMP_SIZE are defined by byte-size, but the size of 'kprobe_opcode_t' depends on the architecture. Therefore, we must be careful when calculating addresses using those macros. Link: https://lkml.kernel.org/r/163163040680.489837.12133032364499833736.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: Add assertions for required lockMasami Hiramatsu1-7/+12
Add assertions for required locks instead of comment it so that the lockdep can inspect locks automatically. Link: https://lkml.kernel.org/r/163163039572.489837.18011973177537476885.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: Fix coding style issuesMasami Hiramatsu1-114/+122
Fix coding style issues reported by checkpatch.pl and update comments to quote variable names and add "()" to function name. One TODO comment in __disarm_kprobe() is removed because it has been done by following commit. Link: https://lkml.kernel.org/r/163163037468.489837.4282347782492003960.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: treewide: Cleanup the error messages for kprobesMasami Hiramatsu1-20/+16
This clean up the error/notification messages in kprobes related code. Basically this defines 'pr_fmt()' macros for each files and update the messages which describes - what happened, - what is the kernel going to do or not do, - is the kernel fine, - what can the user do about it. Also, if the message is not needed (e.g. the function returns unique error code, or other error message is already shown.) remove it, and replace the message with WARN_*() macros if suitable. Link: https://lkml.kernel.org/r/163163036568.489837.14085396178727185469.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: Make arch_check_ftrace_location staticPunit Agrawal1-2/+2
arch_check_ftrace_location() was introduced as a weak function in commit f7f242ff004499 ("kprobes: introduce weak arch_check_ftrace_location() helper function") to allow architectures to handle kprobes call site on their own. Recently, the only architecture (csky) to implement arch_check_ftrace_location() was migrated to using the common version. As a result, further cleanup the code to drop the weak attribute and rename the function to remove the architecture specific implementation. Link: https://lkml.kernel.org/r/163163035673.489837.2367816318195254104.stgit@devnote2 Signed-off-by: Punit Agrawal <punitagrawal@gmail.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobe: Simplify prepare_kprobe() by dropping redundant versionPunit Agrawal1-14/+9
The function prepare_kprobe() is called during kprobe registration and is responsible for ensuring any architecture related preparation for the kprobe is done before returning. One of two versions of prepare_kprobe() is chosen depending on the availability of KPROBE_ON_FTRACE in the kernel configuration. Simplify the code by dropping the version when KPROBE_ON_FTRACE is not selected - instead relying on kprobe_ftrace() to return false when KPROBE_ON_FTRACE is not set. No functional change. Link: https://lkml.kernel.org/r/163163033696.489837.9264661820279300788.stgit@devnote2 Signed-off-by: Punit Agrawal <punitagrawal@gmail.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: Use helper to parse boolean input from userspacePunit Agrawal1-22/+6
The "enabled" file provides a debugfs interface to arm / disarm kprobes in the kernel. In order to parse the buffer containing the values written from userspace, the callback manually parses the user input to convert it to a boolean value. As taking a string value from userspace and converting it to boolean is a common operation, a helper kstrtobool_from_user() is already available in the kernel. Update the callback to use the common helper to parse the write buffer from userspace. Link: https://lkml.kernel.org/r/163163032637.489837.10678039554832855327.stgit@devnote2 Signed-off-by: Punit Agrawal <punitagrawal@gmail.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30kprobes: Do not use local variable when creating debugfs filePunit Agrawal1-2/+1
debugfs_create_file() takes a pointer argument that can be used during file operation callbacks (accessible via i_private in the inode structure). An obvious requirement is for the pointer to refer to valid memory when used. When creating the debugfs file to dynamically enable / disable kprobes, a pointer to local variable is passed to debugfs_create_file(); which will go out of scope when the init function returns. The reason this hasn't triggered random memory corruption is because the pointer is not accessed during the debugfs file callbacks. Since the enabled state is managed by the kprobes_all_disabled global variable, the local variable is not needed. Fix the incorrect (and unnecessary) usage of local variable during debugfs_file_create() by passing NULL instead. Link: https://lkml.kernel.org/r/163163031686.489837.4476867635937014973.stgit@devnote2 Fixes: bf8f6e5b3e51 ("Kprobes: The ON/OFF knob thru debugfs") Signed-off-by: Punit Agrawal <punitagrawal@gmail.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-26Merge tag 'timers-urgent-2021-09-26' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Thomas Gleixner: "A single fix for the recently introduced regression in posix CPU timers which failed to stop the timer when requested. That caused unexpected signals to be sent to the process/thread causing malfunction" * tag 'timers-urgent-2021-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: posix-cpu-timers: Prevent spuriously armed 0-value itimer
2021-09-26Merge tag 'irq-urgent-2021-09-26' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "A set of fixes for interrupt chip drivers: - Work around a bad GIC integration on a Renesas platform which can't handle byte-sized MMIO access - Plug a potential memory leak in the GICv4 driver - Fix a regression in the Armada 370-XP IPI code which was caused by issuing EOI instack of ACK. - A couple of small fixes here and there" * tag 'irq-urgent-2021-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/gic: Work around broken Renesas integration irqchip/renesas-rza1: Use semicolons instead of commas irqchip/gic-v3-its: Fix potential VPE leak on error irqchip/goldfish-pic: Select GENERIC_IRQ_CHIP to fix build irqchip/mbigen: Repair non-kernel-doc notation irqdomain: Change the type of 'size' in __irq_domain_add() to be consistent irqchip/armada-370-xp: Fix ack/eoi breakage Documentation: Fix irq-domain.rst build warning
2021-09-25Merge tag 'block-5.15-2021-09-25' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+8
Pull block fixes from Jens Axboe: - NVMe pull request via Christoph: - keep ctrl->namespaces ordered (Christoph Hellwig) - fix incorrect h2cdata pdu offset accounting in nvme-tcp (Sagi Grimberg) - handled updated hw_queues in nvme-fc more carefully (Daniel Wagner, James Smart) - md lock order fix (Christoph) - fallocate locking fix (Ming) - blktrace UAF fix (Zhihao) - rq-qos bio tracking fix (Ming) * tag 'block-5.15-2021-09-25' of git://git.kernel.dk/linux-block: block: hold ->invalidate_lock in blkdev_fallocate blktrace: Fix uaf in blk_trace access after removing by sysfs block: don't call rq_qos_ops->done_bio if the bio isn't tracked md: fix a lock order reversal in md_alloc nvme: keep ctrl->namespaces ordered nvme-tcp: fix incorrect h2cdata pdu offset accounting nvme-fc: remove freeze/unfreeze around update_nr_hw_queues nvme-fc: avoid race between time out and tear down nvme-fc: update hardware queues before using them
2021-09-24blktrace: Fix uaf in blk_trace access after removing by sysfsZhihao Cheng1-0/+8
There is an use-after-free problem triggered by following process: P1(sda) P2(sdb) echo 0 > /sys/block/sdb/trace/enable blk_trace_remove_queue synchronize_rcu blk_trace_free relay_close rcu_read_lock __blk_add_trace trace_note_tsk (Iterate running_trace_list) relay_close_buf relay_destroy_buf kfree(buf) trace_note(sdb's bt) relay_reserve buf->offset <- nullptr deference (use-after-free) !!! rcu_read_unlock [ 502.714379] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 502.715260] #PF: supervisor read access in kernel mode [ 502.715903] #PF: error_code(0x0000) - not-present page [ 502.716546] PGD 103984067 P4D 103984067 PUD 17592b067 PMD 0 [ 502.717252] Oops: 0000 [#1] SMP [ 502.720308] RIP: 0010:trace_note.isra.0+0x86/0x360 [ 502.732872] Call Trace: [ 502.733193] __blk_add_trace.cold+0x137/0x1a3 [ 502.733734] blk_add_trace_rq+0x7b/0xd0 [ 502.734207] blk_add_trace_rq_issue+0x54/0xa0 [ 502.734755] blk_mq_start_request+0xde/0x1b0 [ 502.735287] scsi_queue_rq+0x528/0x1140 ... [ 502.742704] sg_new_write.isra.0+0x16e/0x3e0 [ 502.747501] sg_ioctl+0x466/0x1100 Reproduce method: ioctl(/dev/sda, BLKTRACESETUP, blk_user_trace_setup[buf_size=127]) ioctl(/dev/sda, BLKTRACESTART) ioctl(/dev/sdb, BLKTRACESETUP, blk_user_trace_setup[buf_size=127]) ioctl(/dev/sdb, BLKTRACESTART) echo 0 > /sys/block/sdb/trace/enable & // Add delay(mdelay/msleep) before kernel enters blk_trace_free() ioctl$SG_IO(/dev/sda, SG_IO, ...) // Enters trace_note_tsk() after blk_trace_free() returned // Use mdelay in rcu region rather than msleep(which may schedule out) Remove blk_trace from running_list before calling blk_trace_free() by sysfs if blk_trace is at Blktrace_running state. Fixes: c71a896154119f ("blktrace: add ftrace plugin") Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Link: https://lore.kernel.org/r/20210923134921.109194-1-chengzhihao1@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-09-24Merge tag 'irqchip-fixes-5.15-1' of ↵Thomas Gleixner1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes from Marc Zyngier: - Work around a bad GIC integration on a Renesas platform, where the interconnect cannot deal with byte-sized MMIO accesses - Cleanup another Renesas driver abusing the comma operator - Fix a potential GICv4 memory leak on an error path - Make the type of 'size' consistent with the rest of the code in __irq_domain_add() - Fix a regression in the Armada 370-XP IPI path - Fix the build for the obviously unloved goldfish-pic - Some documentation fixes Link: https://lore.kernel.org/r/20210924090933.2766857-1-maz@kernel.org
2021-09-23posix-cpu-timers: Prevent spuriously armed 0-value itimerFrederic Weisbecker1-1/+2
Resetting/stopping an itimer eventually leads to it being reprogrammed with an actual "0" value. As a result the itimer expires on the next tick, triggering an unexpected signal. To fix this, make sure that struct signal_struct::it[CPUCLOCK_PROF/VIRT]::expires is set to 0 when setitimer() passes a 0 it_value, indicating that the timer must stop. Fixes: 406dd42bd1ba ("posix-cpu-timers: Force next expiration recalc after itimer reset") Reported-by: Victor Stinner <vstinner@redhat.com> Reported-by: Chris Hixon <linux-kernel-bugs@hixontech.com> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210913145332.232023-1-frederic@kernel.org
2021-09-22entry: rseq: Call rseq_handle_notify_resume() in tracehook_notify_resume()Sean Christopherson2-6/+2
Invoke rseq_handle_notify_resume() from tracehook_notify_resume() now that the two function are always called back-to-back by architectures that have rseq. The rseq helper is stubbed out for architectures that don't support rseq, i.e. this is a nop across the board. Note, tracehook_notify_resume() is horribly named and arguably does not belong in tracehook.h as literally every line of code in it has nothing to do with tracing. But, that's been true since commit a42c6ded827d ("move key_repace_session_keyring() into tracehook_notify_resume()") first usurped tracehook_notify_resume() back in 2012. Punt cleaning that mess up to future patches. No functional change intended. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210901203030.1292304-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-22KVM: rseq: Update rseq when processing NOTIFY_RESUME on xfer to KVM guestSean Christopherson2-4/+14
Invoke rseq's NOTIFY_RESUME handler when processing the flag prior to transferring to a KVM guest, which is roughly equivalent to an exit to userspace and processes many of the same pending actions. While the task cannot be in an rseq critical section as the KVM path is reachable only by via ioctl(KVM_RUN), the side effects that apply to rseq outside of a critical section still apply, e.g. the current CPU needs to be updated if the task is migrated. Clearing TIF_NOTIFY_RESUME without informing rseq can lead to segfaults and other badness in userspace VMMs that use rseq in combination with KVM, e.g. due to the CPU ID being stale after task migration. Fixes: 72c3c0fe54a3 ("x86/kvm: Use generic xfer to guest work function") Reported-by: Peter Foley <pefoley@google.com> Bisected-by: Doug Evans <dje@google.com> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210901203030.1292304-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-22irqdomain: Change the type of 'size' in __irq_domain_add() to be consistentBixuan Cui1-1/+1
The 'size' is used in struct_size(domain, revmap, size) and its input parameter type is 'size_t'(unsigned int). Changing the size to 'unsigned int' to make the type consistent. Signed-off-by: Bixuan Cui <cuibixuan@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210916025203.44841-1-cuibixuan@huawei.com
2021-09-19Merge tag 'perf-urgent-2021-09-19' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf event fix from Thomas Gleixner: "A single fix for the perf core where a value read with READ_ONCE() was checked and then reread which makes all the checks invalid. Reuse the already read value instead" * tag 'perf-urgent-2021-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: events: Reuse value read using READ_ONCE instead of re-reading it
2021-09-19Merge tag 'locking-urgent-2021-09-19' of ↵Linus Torvalds1-20/+45
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "A set of updates for the RT specific reader/writer locking base code: - Make the fast path reader ordering guarantees correct. - Code reshuffling to make the fix simpler" [ This plays ugly games with atomic_add_return_release() because we don't have a plain atomic_add_release(), and should really be cleaned up, I think - Linus ] * tag 'locking-urgent-2021-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rwbase: Take care of ordering guarantee for fastpath reader locking/rwbase: Extract __rwbase_write_trylock() locking/rwbase: Properly match set_and_save_state() to restore_state()
2021-09-17Merge tag 'dma-mapping-5.15-1' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds2-2/+4
Pull dma-mapping fixes from Christoph Hellwig: - page align size in sparc32 arch_dma_alloc (Andreas Larsson) - tone down a new dma-debug message (Hamza Mahfooz) - fix the kerneldoc for dma_map_sg_attrs (me) * tag 'dma-mapping-5.15-1' of git://git.infradead.org/users/hch/dma-mapping: sparc32: page align size in arch_dma_alloc dma-debug: prevent an error message from causing runtime problems dma-mapping: fix the kerneldoc for dma_map_sg_attrs
2021-09-16Merge tag 'net-5.15-rc2' of ↵Linus Torvalds5-44/+22
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from bpf. Current release - regressions: - vhost_net: fix OoB on sendmsg() failure - mlx5: bridge, fix uninitialized variable usage - bnxt_en: fix error recovery regression Current release - new code bugs: - bpf, mm: fix lockdep warning triggered by stack_map_get_build_id_offset() Previous releases - regressions: - r6040: restore MDIO clock frequency after MAC reset - tcp: fix tp->undo_retrans accounting in tcp_sacktag_one() - dsa: flush switchdev workqueue before tearing down CPU/DSA ports Previous releases - always broken: - ptp: dp83640: don't define PAGE0, avoid compiler warning - igc: fix tunnel segmentation offloads - phylink: update SFP selected interface on advertising changes - stmmac: fix system hang caused by eee_ctrl_timer during suspend/resume - mlx5e: fix mutual exclusion between CQE compression and HW TS Misc: - bpf, cgroups: fix cgroup v2 fallback on v1/v2 mixed mode - sfc: fallback for lack of xdp tx queues - hns3: add option to turn off page pool feature" * tag 'net-5.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (67 commits) mlxbf_gige: clear valid_polarity upon open igc: fix tunnel offloading net/{mlx5|nfp|bnxt}: Remove unnecessary RTNL lock assert net: wan: wanxl: define CROSS_COMPILE_M68K selftests: nci: replace unsigned int with int net: dsa: flush switchdev workqueue before tearing down CPU/DSA ports Revert "net: phy: Uniform PHY driver access" net: dsa: destroy the phylink instance on any error in dsa_slave_phy_setup ptp: dp83640: don't define PAGE0 bnx2x: Fix enabling network interfaces without VFs Revert "Revert "ipv4: fix memory leaks in ip_cmsg_send() callers"" tcp: fix tp->undo_retrans accounting in tcp_sacktag_one() net-caif: avoid user-triggerable WARN_ON(1) bpf, selftests: Add test case for mixed cgroup v1/v2 bpf, selftests: Add cgroup v1 net_cls classid helpers bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed mode bpf: Add oversize check before call kvcalloc() net: hns3: fix the timing issue of VF clearing interrupt sources net: hns3: fix the exception when query imp info net: hns3: disable mac in flr process ...
2021-09-15locking/rwbase: Take care of ordering guarantee for fastpath readerBoqun Feng1-2/+19
Readers of rwbase can lock and unlock without taking any inner lock, if that happens, we need the ordering provided by atomic operations to satisfy the ordering semantics of lock/unlock. Without that, considering the follow case: { X = 0 initially } CPU 0 CPU 1 ===== ===== rt_write_lock(); X = 1 rt_write_unlock(): atomic_add(READER_BIAS - WRITER_BIAS, ->readers); // ->readers is READER_BIAS. rt_read_lock(): if ((r = atomic_read(->readers)) < 0) // True atomic_try_cmpxchg(->readers, r, r + 1); // succeed. <acquire the read lock via fast path> r1 = X; // r1 may be 0, because nothing prevent the reordering // of "X=1" and atomic_add() on CPU 1. Therefore audit every usage of atomic operations that may happen in a fast path, and add necessary barriers. Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20210909110203.953991276@infradead.org
2021-09-15locking/rwbase: Extract __rwbase_write_trylock()Peter Zijlstra1-18/+26
The code in rwbase_write_lock() is a little non-obvious vs the read+set 'trylock', extract the sequence into a helper function to clarify the code. This also provides a single site to fix fast-path ordering. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/YUCq3L+u44NDieEJ@hirez.programming.kicks-ass.net
2021-09-15locking/rwbase: Properly match set_and_save_state() to restore_state()Peter Zijlstra1-1/+1
Noticed while looking at the readers race. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20210909110203.828203010@infradead.org
2021-09-15events: Reuse value read using READ_ONCE instead of re-reading itBaptiste Lepers1-1/+1
In perf_event_addr_filters_apply, the task associated with the event (event->ctx->task) is read using READ_ONCE at the beginning of the function, checked, and then re-read from event->ctx->task, voiding all guarantees of the checks. Reuse the value that was read by READ_ONCE to ensure the consistency of the task struct throughout the function. Fixes: 375637bc52495 ("perf/core: Introduce address range filtering") Signed-off-by: Baptiste Lepers <baptiste.lepers@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210906015310.12802-1-baptiste.lepers@gmail.com
2021-09-14memblock: introduce saner 'memblock_free_ptr()' interfaceLinus Torvalds1-2/+2
The boot-time allocation interface for memblock is a mess, with 'memblock_alloc()' returning a virtual pointer, but then you are supposed to free it with 'memblock_free()' that takes a _physical_ address. Not only is that all kinds of strange and illogical, but it actually causes bugs, when people then use it like a normal allocation function, and it fails spectacularly on a NULL pointer: https://lore.kernel.org/all/20210912140820.GD25450@xsang-OptiPlex-9020/ or just random memory corruption if the debug checks don't catch it: https://lore.kernel.org/all/61ab2d0c-3313-aaab-514c-e15b7aa054a0@suse.cz/ I really don't want to apply patches that treat the symptoms, when the fundamental cause is this horribly confusing interface. I started out looking at just automating a sane replacement sequence, but because of this mix or virtual and physical addresses, and because people have used the "__pa()" macro that can take either a regular kernel pointer, or just the raw "unsigned long" address, it's all quite messy. So this just introduces a new saner interface for freeing a virtual address that was allocated using 'memblock_alloc()', and that was kept as a regular kernel pointer. And then it converts a couple of users that are obvious and easy to test, including the 'xbc_nodes' case in lib/bootconfig.c that caused problems. Reported-by: kernel test robot <oliver.sang@intel.com> Fixes: 40caa127f3c7 ("init: bootconfig: Remove all bootconfig data when the init memory is removed") Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller5-44/+22
Daniel Borkmann says: ==================== pull-request: bpf 2021-09-14 The following pull-request contains BPF updates for your *net* tree. We've added 7 non-merge commits during the last 13 day(s) which contain a total of 18 files changed, 334 insertions(+), 193 deletions(-). The main changes are: 1) Fix mmap_lock lockdep splat in BPF stack map's build_id lookup, from Yonghong Song. 2) Fix BPF cgroup v2 program bypass upon net_cls/prio activation, from Daniel Borkmann. 3) Fix kvcalloc() BTF line info splat on oversized allocation attempts, from Bixuan Cui. 4) Fix BPF selftest build of task_pt_regs test for arm64/s390, from Jean-Philippe Brucker. 5) Fix BPF's disasm.{c,h} to dual-license so that it is aligned with bpftool given the former is a build dependency for the latter, from Daniel Borkmann with ACKs from contributors. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-13bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed modeDaniel Borkmann1-40/+10
Fix cgroup v1 interference when non-root cgroup v2 BPF programs are used. Back in the days, commit bd1060a1d671 ("sock, cgroup: add sock->sk_cgroup") embedded per-socket cgroup information into sock->sk_cgrp_data and in order to save 8 bytes in struct sock made both mutually exclusive, that is, when cgroup v1 socket tagging (e.g. net_cls/net_prio) is used, then cgroup v2 falls back to the root cgroup in sock_cgroup_ptr() (&cgrp_dfl_root.cgrp). The assumption made was "there is no reason to mix the two and this is in line with how legacy and v2 compatibility is handled" as stated in bd1060a1d671. However, with Kubernetes more widely supporting cgroups v2 as well nowadays, this assumption no longer holds, and the possibility of the v1/v2 mixed mode with the v2 root fallback being hit becomes a real security issue. Many of the cgroup v2 BPF programs are also used for policy enforcement, just to pick _one_ example, that is, to programmatically deny socket related system calls like connect(2) or bind(2). A v2 root fallback would implicitly cause a policy bypass for the affected Pods. In production environments, we have recently seen this case due to various circumstances: i) a different 3rd party agent and/or ii) a container runtime such as [0] in the user's environment configuring legacy cgroup v1 net_cls tags, which triggered implicitly mentioned root fallback. Another case is Kubernetes projects like kind [1] which create Kubernetes nodes in a container and also add cgroup namespaces to the mix, meaning programs which are attached to the cgroup v2 root of the cgroup namespace get attached to a non-root cgroup v2 path from init namespace point of view. And the latter's root is out of reach for agents on a kind Kubernetes node to configure. Meaning, any entity on the node setting cgroup v1 net_cls tag will trigger the bypass despite cgroup v2 BPF programs attached to the namespace root. Generally, this mutual exclusiveness does not hold anymore in today's user environments and makes cgroup v2 usage from BPF side fragile and unreliable. This fix adds proper struct cgroup pointer for the cgroup v2 case to struct sock_cgroup_data in order to address these issues; this implicitly also fixes the tradeoffs being made back then with regards to races and refcount leaks as stated in bd1060a1d671, and removes the fallback, so that cgroup v2 BPF programs always operate as expected. [0] https://github.com/nestybox/sysbox/ [1] https://kind.sigs.k8s.io/ Fixes: bd1060a1d671 ("sock, cgroup: add sock->sk_cgroup") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Stanislav Fomichev <sdf@google.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/bpf/20210913230759.2313-1-daniel@iogearbox.net
2021-09-13bpf: Add oversize check before call kvcalloc()Bixuan Cui1-0/+2
Commit 7661809d493b ("mm: don't allow oversized kvmalloc() calls") add the oversize check. When the allocation is larger than what kmalloc() supports, the following warning triggered: WARNING: CPU: 0 PID: 8408 at mm/util.c:597 kvmalloc_node+0x108/0x110 mm/util.c:597 Modules linked in: CPU: 0 PID: 8408 Comm: syz-executor221 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:kvmalloc_node+0x108/0x110 mm/util.c:597 Call Trace: kvmalloc include/linux/mm.h:806 [inline] kvmalloc_array include/linux/mm.h:824 [inline] kvcalloc include/linux/mm.h:829 [inline] check_btf_line kernel/bpf/verifier.c:9925 [inline] check_btf_info kernel/bpf/verifier.c:10049 [inline] bpf_check+0xd634/0x150d0 kernel/bpf/verifier.c:13759 bpf_prog_load kernel/bpf/syscall.c:2301 [inline] __sys_bpf+0x11181/0x126e0 kernel/bpf/syscall.c:4587 __do_sys_bpf kernel/bpf/syscall.c:4691 [inline] __se_sys_bpf kernel/bpf/syscall.c:4689 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4689 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported-by: syzbot+f3e749d4c662818ae439@syzkaller.appspotmail.com Signed-off-by: Bixuan Cui <cuibixuan@huawei.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210911005557.45518-1-cuibixuan@huawei.com
2021-09-13dma-debug: prevent an error message from causing runtime problemsHamza Mahfooz1-1/+2
For some drivers, that use the DMA API. This error message can be reached several millions of times per second, causing spam to the kernel's printk buffer and bringing the CPU usage up to 100% (so, it should be rate limited). However, since there is at least one driver that is in the mainline and suffers from the error condition, it is more useful to err_printk() here instead of just rate limiting the error message (in hopes that it will make it easier for other drivers that suffer from this issue to be spotted). Link: https://lkml.kernel.org/r/fd67fbac-64bf-f0ea-01e1-5938ccfab9d0@arm.com Reported-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Hamza Mahfooz <someguy@effective-light.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-09-12Merge tag 'sched_urgent_for_v5.15_rc1' of ↵Linus Torvalds2-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Borislav Petkov: - Make sure the idle timer expires in hardirq context, on PREEMPT_RT - Make sure the run-queue balance callback is invoked only on the outgoing CPU * tag 'sched_urgent_for_v5.15_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Prevent balance_push() on remote runqueues sched/idle: Make the idle timer expire in hard interrupt context
2021-09-12Merge tag 'locking_urgent_for_v5.15_rc1' of ↵Linus Torvalds3-84/+118
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Borislav Petkov: - Fix the futex PI requeue machinery to not return to userspace in inconsistent state - Avoid a potential null pointer dereference in the ww_mutex deadlock check - Other smaller cleanups and optimizations * tag 'locking_urgent_for_v5.15_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rtmutex: Fix ww_mutex deadlock check futex: Remove unused variable 'vpid' in futex_proxy_trylock_atomic() futex: Avoid redundant task lookup futex: Clarify comment for requeue_pi_wake_futex() futex: Prevent inconsistent state and exit race futex: Return error code instead of assigning it without effect locking/rwsem: Add missing __init_rwsem() for PREEMPT_RT
2021-09-11Merge tag 'trace-v5.15-3' of ↵Linus Torvalds1-19/+18
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Minor fixes to the processing of the bootconfig tree" * tag 'trace-v5.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: bootconfig: Rename xbc_node_find_child() to xbc_node_find_subkey() tracing/boot: Fix to check the histogram control param is a leaf node tracing/boot: Fix trace_boot_hist_add_array() to check array is value
2021-09-10bpf, mm: Fix lockdep warning triggered by stack_map_get_build_id_offset()Yonghong Song1-2/+8
Currently the bpf selftest "get_stack_raw_tp" triggered the warning: [ 1411.304463] WARNING: CPU: 3 PID: 140 at include/linux/mmap_lock.h:164 find_vma+0x47/0xa0 [ 1411.304469] Modules linked in: bpf_testmod(O) [last unloaded: bpf_testmod] [ 1411.304476] CPU: 3 PID: 140 Comm: systemd-journal Tainted: G W O 5.14.0+ #53 [ 1411.304479] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 1411.304481] RIP: 0010:find_vma+0x47/0xa0 [ 1411.304484] Code: de 48 89 ef e8 ba f5 fe ff 48 85 c0 74 2e 48 83 c4 08 5b 5d c3 48 8d bf 28 01 00 00 be ff ff ff ff e8 2d 9f d8 00 85 c0 75 d4 <0f> 0b 48 89 de 48 8 [ 1411.304487] RSP: 0018:ffffabd440403db8 EFLAGS: 00010246 [ 1411.304490] RAX: 0000000000000000 RBX: 00007f00ad80a0e0 RCX: 0000000000000000 [ 1411.304492] RDX: 0000000000000001 RSI: ffffffff9776b144 RDI: ffffffff977e1b0e [ 1411.304494] RBP: ffff9cf5c2f50000 R08: ffff9cf5c3eb25d8 R09: 00000000fffffffe [ 1411.304496] R10: 0000000000000001 R11: 00000000ef974e19 R12: ffff9cf5c39ae0e0 [ 1411.304498] R13: 0000000000000000 R14: 0000000000000000 R15: ffff9cf5c39ae0e0 [ 1411.304501] FS: 00007f00ae754780(0000) GS:ffff9cf5fba00000(0000) knlGS:0000000000000000 [ 1411.304504] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1411.304506] CR2: 000000003e34343c CR3: 0000000103a98005 CR4: 0000000000370ee0 [ 1411.304508] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1411.304510] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1411.304512] Call Trace: [ 1411.304517] stack_map_get_build_id_offset+0x17c/0x260 [ 1411.304528] __bpf_get_stack+0x18f/0x230 [ 1411.304541] bpf_get_stack_raw_tp+0x5a/0x70 [ 1411.305752] RAX: 0000000000000000 RBX: 5541f689495641d7 RCX: 0000000000000000 [ 1411.305756] RDX: 0000000000000001 RSI: ffffffff9776b144 RDI: ffffffff977e1b0e [ 1411.305758] RBP: ffff9cf5c02b2f40 R08: ffff9cf5ca7606c0 R09: ffffcbd43ee02c04 [ 1411.306978] bpf_prog_32007c34f7726d29_bpf_prog1+0xaf/0xd9c [ 1411.307861] R10: 0000000000000001 R11: 0000000000000044 R12: ffff9cf5c2ef60e0 [ 1411.307865] R13: 0000000000000005 R14: 0000000000000000 R15: ffff9cf5c2ef6108 [ 1411.309074] bpf_trace_run2+0x8f/0x1a0 [ 1411.309891] FS: 00007ff485141700(0000) GS:ffff9cf5fae00000(0000) knlGS:0000000000000000 [ 1411.309896] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1411.311221] syscall_trace_enter.isra.20+0x161/0x1f0 [ 1411.311600] CR2: 00007ff48514d90e CR3: 0000000107114001 CR4: 0000000000370ef0 [ 1411.312291] do_syscall_64+0x15/0x80 [ 1411.312941] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1411.313803] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 1411.314223] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1411.315082] RIP: 0033:0x7f00ad80a0e0 [ 1411.315626] Call Trace: [ 1411.315632] stack_map_get_build_id_offset+0x17c/0x260 To reproduce, first build `test_progs` binary: make -C tools/testing/selftests/bpf -j60 and then run the binary at tools/testing/selftests/bpf directory: ./test_progs -t get_stack_raw_tp The warning is due to commit 5b78ed24e8ec ("mm/pagemap: add mmap_assert_locked() annotations to find_vma*()") which added mmap_assert_locked() in find_vma() function. The mmap_assert_locked() function asserts that mm->mmap_lock needs to be held. But this is not the case for bpf_get_stack() or bpf_get_stackid() helper (kernel/bpf/stackmap.c), which uses mmap_read_trylock_non_owner() instead. Since mm->mmap_lock is not held in bpf_get_stack[id]() use case, the above warning is emitted during test run. This patch fixed the issue by (1). using mmap_read_trylock() instead of mmap_read_trylock_non_owner() to satisfy lockdep checking in find_vma(), and (2). droping lockdep for mmap_lock right before the irq_work_queue(). The function mmap_read_trylock_non_owner() is also removed since after this patch nobody calls it any more. Fixes: 5b78ed24e8ec ("mm/pagemap: add mmap_assert_locked() annotations to find_vma*()") Suggested-by: Jason Gunthorpe <jgg@ziepe.ca> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Luigi Rizzo <lrizzo@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: linux-mm@kvack.org Link: https://lore.kernel.org/bpf/20210909155000.1610299-1-yhs@fb.com
2021-09-09bootconfig: Rename xbc_node_find_child() to xbc_node_find_subkey()Masami Hiramatsu1-12/+12
Rename xbc_node_find_child() to xbc_node_find_subkey() for clarifying that function returns a key node (no value node). Since there are xbc_node_for_each_child() (loop on all child nodes) and xbc_node_for_each_subkey() (loop on only subkey nodes), this name distinction is necessary to avoid confusing users. Link: https://lkml.kernel.org/r/163119459826.161018.11200274779483115300.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-09tracing/boot: Fix to check the histogram control param is a leaf nodeMasami Hiramatsu1-3/+3
Since xbc_node_find_child() doesn't ensure the returned node is a leaf node (key-value pair or do not have subkeys), use xbc_node_find_value to ensure the histogram control parameter is a leaf node in trace_boot_compose_hist_cmd(). Link: https://lkml.kernel.org/r/163119459059.161018.18341288218424528962.stgit@devnote2 Fixes: e66ed86ca6c5 ("tracing/boot: Add per-event histogram action options") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-09tracing/boot: Fix trace_boot_hist_add_array() to check array is valueMasami Hiramatsu1-4/+3
trace_boot_hist_add_array() uses the combination of xbc_node_find_child() and xbc_node_get_child() to get the child node of the key node. But since it missed to check the child node is data node or not, user can pass the subkey node for the array node (anode). To avoid this issue, check the array node is a data node. Actually, there is xbc_node_find_value(node, key, vnode), which ensures the @vnode is a value node, so use it in trace_boot_hist_add_array() to fix this issue. Link: https://lkml.kernel.org/r/163119458308.161018.1516455973625940212.stgit@devnote2 Fixes: e66ed86ca6c5 ("tracing/boot: Add per-event histogram action options") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-09Merge tag 'trace-v5.15-2' of ↵Linus Torvalds8-21/+50
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull more tracing updates from Steven Rostedt: - Add migrate-disable counter to tracing header - Fix error handling in event probes - Fix missed unlock in osnoise in error path - Fix merge issue with tools/bootconfig - Clean up bootconfig data when init memory is removed - Fix bootconfig to loop only on subkeys - Have kernel command lines override bootconfig options - Increase field counts for synthetic events - Have histograms dynamic allocate event elements to save space - Fixes in testing and documentation * tag 'trace-v5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/boot: Fix to loop on only subkeys selftests/ftrace: Exclude "(fault)" in testing add/remove eprobe events tracing: Dynamically allocate the per-elt hist_elt_data array tracing: synth events: increase max fields count tools/bootconfig: Show whole test command for each test case bootconfig: Fix missing return check of xbc_node_compose_key function tools/bootconfig: Fix tracing_on option checking in ftrace2bconf.sh docs: bootconfig: Add how to use bootconfig for kernel parameters init/bootconfig: Reorder init parameter from bootconfig and cmdline init: bootconfig: Remove all bootconfig data when the init memory is removed tracing/osnoise: Fix missed cpus_read_unlock() in start_per_cpu_kthreads() tracing: Fix some alloc_event_probe() error handling bugs tracing: Add migrate-disabled counter to tracing output.
2021-09-09sched: Prevent balance_push() on remote runqueuesThomas Gleixner1-3/+3
sched_setscheduler() and rt_mutex_setprio() invoke the run-queue balance callback after changing priorities or the scheduling class of a task. The run-queue for which the callback is invoked can be local or remote. That's not a problem for the regular rq::push_work which is serialized with a busy flag in the run-queue struct, but for the balance_push() work which is only valid to be invoked on the outgoing CPU that's wrong. It not only triggers the debug warning, but also leaves the per CPU variable push_work unprotected, which can result in double enqueues on the stop machine list. Remove the warning and validate that the function is invoked on the outgoing CPU. Fixes: ae7927023243 ("sched: Optimize finish_lock_switch()") Reported-by: Sebastian Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/87zgt1hdw7.ffs@tglx
2021-09-09sched/idle: Make the idle timer expire in hard interrupt contextSebastian Andrzej Siewior1-2/+2
The intel powerclamp driver will setup a per-CPU worker with RT priority. The worker will then invoke play_idle() in which it remains in the idle poll loop until it is stopped by the timer it started earlier. That timer needs to expire in hard interrupt context on PREEMPT_RT. Otherwise the timer will expire in ksoftirqd as a SOFT timer but that task won't be scheduled on the CPU because its priority is lower than the priority of the worker which is in the idle loop. Always expire the idle timer in hard interrupt context. Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210906113034.jgfxrjdvxnjqgtmc@linutronix.de
2021-09-09locking/rtmutex: Fix ww_mutex deadlock checkPeter Zijlstra1-1/+1
Dan reported that rt_mutex_adjust_prio_chain() can be called with .orig_waiter == NULL however commit a055fcc132d4 ("locking/rtmutex: Return success on deadlock for ww_mutex waiters") unconditionally dereferences it. Since both call-sites that have .orig_waiter == NULL don't care for the return value, simply disable the deadlock squash by adding the NULL check. Notably, both callers use the deadlock condition as a termination condition for the iteration; once detected, it is sure that (de)boosting is done. Arguably step [3] would be a more natural termination point, but it's dubious whether adding a third deadlock detection state would improve the code. Fixes: a055fcc132d4 ("locking/rtmutex: Return success on deadlock for ww_mutex waiters") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/YS9La56fHMiCCo75@hirez.programming.kicks-ass.net
2021-09-08Merge branches 'akpm' and 'akpm-hotfixes' (patches from Andrew)Linus Torvalds4-89/+41
Merge yet more updates and hotfixes from Andrew Morton: "Post-linux-next material, based upon latest upstream to catch the now-merged dependencies: - 10 patches. Subsystems affected by this patch series: mm (vmstat and migration) and compat. And bunch of hotfixes, mostly cc:stable: - 8 patches. Subsystems affected by this patch series: mm (hmm, hugetlb, vmscan, pagealloc, pagemap, kmemleak, mempolicy, and memblock)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: arch: remove compat_alloc_user_space compat: remove some compat entry points mm: simplify compat numa syscalls mm: simplify compat_sys_move_pages kexec: avoid compat_alloc_user_space kexec: move locking into do_kexec_load mm: migrate: change to use bool type for 'page_was_mapped' mm: migrate: fix the incorrect function name in comments mm: migrate: introduce a local variable to get the number of pages mm/vmstat: protect per cpu variables with preempt disable on RT * emailed hotfixes from Andrew Morton <akpm@linux-foundation.org>: nds32/setup: remove unused memblock_region variable in setup_memory() mm/mempolicy: fix a race between offset_il_node and mpol_rebind_task mm/kmemleak: allow __GFP_NOLOCKDEP passed to kmemleak's gfp mmap_lock: change trace and locking order mm/page_alloc.c: avoid accessing uninitialized pcp page migratetype mm,vmscan: fix divide by zero in get_scan_count mm/hugetlb: initialize hugetlb_usage in mm_init mm/hmm: bypass devmap pte when all pfn requested flags are fulfilled
2021-09-08mm/hugetlb: initialize hugetlb_usage in mm_initLiu Zixian1-0/+1
After fork, the child process will get incorrect (2x) hugetlb_usage. If a process uses 5 2MB hugetlb pages in an anonymous mapping, HugetlbPages: 10240 kB and then forks, the child will show, HugetlbPages: 20480 kB The reason for double the amount is because hugetlb_usage will be copied from the parent and then increased when we copy page tables from parent to child. Child will have 2x actual usage. Fix this by adding hugetlb_count_init in mm_init. Link: https://lkml.kernel.org/r/20210826071742.877-1-liuzixian4@huawei.com Fixes: 5d317b2b6536 ("mm: hugetlb: proc: add HugetlbPages field to /proc/PID/status") Signed-off-by: Liu Zixian <liuzixian4@huawei.com> Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08arch: remove compat_alloc_user_spaceArnd Bergmann1-21/+0
All users of compat_alloc_user_space() and copy_in_user() have been removed from the kernel, only a few functions in sparc remain that can be changed to calling arch_copy_in_user() instead. Link: https://lkml.kernel.org/r/20210727144859.4150043-7-arnd@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08compat: remove some compat entry pointsArnd Bergmann1-5/+0
These are all handled correctly when calling the native system call entry point, so remove the special cases. Link: https://lkml.kernel.org/r/20210727144859.4150043-6-arnd@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08kexec: avoid compat_alloc_user_spaceArnd Bergmann1-36/+25
kimage_alloc_init() expects a __user pointer, so compat_sys_kexec_load() uses compat_alloc_user_space() to convert the layout and put it back onto the user space caller stack. Moving the user space access into the syscall handler directly actually makes the code simpler, as the conversion for compat mode can now be done on kernel memory. Link: https://lkml.kernel.org/r/20210727144859.4150043-3-arnd@kernel.org Link: https://lore.kernel.org/lkml/YPbtsU4GX6PL7%2F42@infradead.org/ Link: https://lore.kernel.org/lkml/m1y2cbzmnw.fsf@fess.ebiederm.org/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Co-developed-by: Eric Biederman <ebiederm@xmission.com> Co-developed-by: Christoph Hellwig <hch@infradead.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Feng Tang <feng.tang@intel.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>