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52501 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Linus Torvalds
|
864be1277d |
tracing fix for 7.2:
- Move rb_desc->nr_page_va before updating dynamic array The rb_descr->page_va is a dynamic array counted by nr_page_va. But the updating of the page_va[] is done before the nr_page_va is incremented causing a build with CONFIG_UBSAN_BOUNDS to flag it as an overflow. Move the increment of the counted by value before the array element is updated. - Propagate errors from remote event bulk updates The return value of trace_remote_enable_event() was not being checked by remote_events_dir_enable_write() where it would silently fail. Have it check the return value and propagate that back up to user space. - Fix resource leak on mmiotrace trace_pipe close The mmiotrace tracer was created in 2008 before the trace_pipe had a close callback to allow tracers to do clean up from trace_pipe open. The trace_pipe close cleanup callback was added in 2009 but the mmiotrace tracer was not updated. It had a hack to do the cleanup in the read call, where it may leak if user space did not read the entire buffer. Add a callback to mmiotrace trace_pipe close do to the cleanup properly. - Fix a possible NULL pointer dereference in the mmiotrace tracer If the mmio_pipe_open() fails to find a PCI device, it will set the hiter->dev pointer to NULL. The read function will blindly dereference that pointer. Fix the read call to check to see if that pointer is populated before dereferencing it. - Fix union collision of module and refcnt for dynamic events In 'struct trace_event_call', the 'module' pointer and the 'refcnt' atomic variable share the same memory space in a union. The filter on module logic only checked if the 'module' was set to determine if the event belonged to the module. As dynamic events are always builtin, it doesn't need the 'module' field of the structure and used a refcount. But the module filtering logic would then mistaken these dynamic events as a module and call module_name(event->module) on it. Add a check to see if the event is a dynamic event and if so, do not check it for being part of the given module. - Reset the top level buffer in selftests before running instances The ftracetest selftest initializes each instance before executing the tests. But it does not reset the top level buffer. Dynamic events are only added and removed by the top level so any left over dynamic events will not be removed by the reset in the instances. Left over dynamic events can cause the tests to incorrectly fail. Reset the top level buffer before running the instances. - Make the context_switch counter 64 bit The code to read user space for a system call trace event or for a trace_marker will disable migration, enable preemption, read user space into a per CPU buffer, disable preemption and enable migration again. It checks if the per CPU context switch counter to see if it changed, and if it did not, it would know that the per CPU buffer was not touched by another task. But the save counter was 32 bit and it would compare it to the 64 bit context_switch variable. A long running system could have the context_switch variable greater that 1<<32 in which case the compare will always fail. The compare will promote the 32 bit int saved value to 64 bit and compare it to the full 64 bit counter. Since the top 32 bits of the saved value was zero, it would never match. - Fix a use-after-free of the event_enable trigger The event_enable trigger allows for enabling one event when another event is triggered. When the trigger is removed, it must go through a synchronization phase to make sure it is not triggered again. The trigger itself is delayed by the "bulk delay" logic that was recently added. But the code that frees the event_enable data used to rely on the trigger code to do the synchronization. Now that the code uses the call RCU functions (and a workqueue), that delay no longer is there. Add a callback private_data_free() function that allows triggers to clean up data after the synchronization phase has completed. - Move the module_ref counter into the delay callback Since an event of the event_enable trigger can enable an event for a module, it ups the module ref count for that event's module. This prevents the event from trying to enable an event that no longer exists and cause a use-after-free bug. The ref counter was set back down when the trigger was removed but not after thy synchronization phase. This could lead to the module data being accessed after module was unloaded. Move the module ref decrement into the private_data_free() callback of the event_enable trigger. - Add mutex to protect parser in ftrace filtering The set_ftrace_filter file uses a parsing descriptor that is allocated at open and modified by writes. If multiple threads were to write to the descriptor at the same time, it can corrupt the parser. Add a mutex around the modifications of the parser descriptor. - Fix possible corruption in perf syscall tracing The perf system call trace events can now read user space. To do so, the reads of user space enable preemption and disables it again. During this time that preemption is enabled, the task can migrate. The perf event list head is assigned via a per CPU pointer. It is done before the user space part is called. If the user space reading migrates the task to another CPU, then the head pointer is no longer valid. Re-assign the head pointer after the reading of user space to keep it using the correct data. -----BEGIN PGP SIGNATURE----- iIoEABYKADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCamYDGhQccm9zdGVkdEBn b29kbWlzLm9yZwAKCRAp5XQQmuv6qkhYAP9G5wDTVQQzitl900iWp9rvQ2Qm5UWN JDnK2HO1elmj0AD8CRiHBI5W3O2yUmoO4bOFZ9YFXz+DqJ1jwkDs5FfqjAU= =EMD9 -----END PGP SIGNATURE----- Merge tag 'trace-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Move rb_desc->nr_page_va before updating dynamic array The rb_descr->page_va is a dynamic array counted by nr_page_va. But the updating of the page_va[] is done before the nr_page_va is incremented causing a build with CONFIG_UBSAN_BOUNDS to flag it as an overflow. Move the increment of the counted by value before the array element is updated. - Propagate errors from remote event bulk updates The return value of trace_remote_enable_event() was not being checked by remote_events_dir_enable_write() where it would silently fail. Have it check the return value and propagate that back up to user space. - Fix resource leak on mmiotrace trace_pipe close The mmiotrace tracer was created in 2008 before the trace_pipe had a close callback to allow tracers to do clean up from trace_pipe open. The trace_pipe close cleanup callback was added in 2009 but the mmiotrace tracer was not updated. It had a hack to do the cleanup in the read call, where it may leak if user space did not read the entire buffer. Add a callback to mmiotrace trace_pipe close do to the cleanup properly. - Fix a possible NULL pointer dereference in the mmiotrace tracer If the mmio_pipe_open() fails to find a PCI device, it will set the hiter->dev pointer to NULL. The read function will blindly dereference that pointer. Fix the read call to check to see if that pointer is populated before dereferencing it. - Fix union collision of module and refcnt for dynamic events In 'struct trace_event_call', the 'module' pointer and the 'refcnt' atomic variable share the same memory space in a union. The filter on module logic only checked if the 'module' was set to determine if the event belonged to the module. As dynamic events are always builtin, it doesn't need the 'module' field of the structure and used a refcount. But the module filtering logic would then mistaken these dynamic events as a module and call module_name(event->module) on it. Add a check to see if the event is a dynamic event and if so, do not check it for being part of the given module. - Reset the top level buffer in selftests before running instances The ftracetest selftest initializes each instance before executing the tests. But it does not reset the top level buffer. Dynamic events are only added and removed by the top level so any left over dynamic events will not be removed by the reset in the instances. Left over dynamic events can cause the tests to incorrectly fail. Reset the top level buffer before running the instances. - Make the context_switch counter 64 bit The code to read user space for a system call trace event or for a trace_marker will disable migration, enable preemption, read user space into a per CPU buffer, disable preemption and enable migration again. It checks if the per CPU context switch counter to see if it changed, and if it did not, it would know that the per CPU buffer was not touched by another task. But the save counter was 32 bit and it would compare it to the 64 bit context_switch variable. A long running system could have the context_switch variable greater that 1<<32 in which case the compare will always fail. The compare will promote the 32 bit int saved value to 64 bit and compare it to the full 64 bit counter. Since the top 32 bits of the saved value was zero, it would never match. - Fix a use-after-free of the event_enable trigger The event_enable trigger allows for enabling one event when another event is triggered. When the trigger is removed, it must go through a synchronization phase to make sure it is not triggered again. The trigger itself is delayed by the "bulk delay" logic that was recently added. But the code that frees the event_enable data used to rely on the trigger code to do the synchronization. Now that the code uses the call RCU functions (and a workqueue), that delay no longer is there. Add a callback private_data_free() function that allows triggers to clean up data after the synchronization phase has completed. - Move the module_ref counter into the delay callback Since an event of the event_enable trigger can enable an event for a module, it ups the module ref count for that event's module. This prevents the event from trying to enable an event that no longer exists and cause a use-after-free bug. The ref counter was set back down when the trigger was removed but not after thy synchronization phase. This could lead to the module data being accessed after module was unloaded. Move the module ref decrement into the private_data_free() callback of the event_enable trigger. - Add mutex to protect parser in ftrace filtering The set_ftrace_filter file uses a parsing descriptor that is allocated at open and modified by writes. If multiple threads were to write to the descriptor at the same time, it can corrupt the parser. Add a mutex around the modifications of the parser descriptor. - Fix possible corruption in perf syscall tracing The perf system call trace events can now read user space. To do so, the reads of user space enable preemption and disables it again. During this time that preemption is enabled, the task can migrate. The perf event list head is assigned via a per CPU pointer. It is done before the user space part is called. If the user space reading migrates the task to another CPU, then the head pointer is no longer valid. Re-assign the head pointer after the reading of user space to keep it using the correct data. * tag 'trace-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: perf: Fix stale head for perf syscall tracing ftrace: Add global mutex to serialize trace_parser access tracing: Delay module ref count for "enable_event" trigger tracing: Fix use-after-free freeing trigger private data tracing: Fix context switch counter truncation selftests/ftrace: Reset triggers at top level before instance loop tracing: Fix union collision of module and refcnt for dynamic events tracing: Fix mmiotrace possible NULL dereferencing of hiter->dev tracing: Fix resource leak on mmiotrace trace_pipe close tracing: Propagate errors from remote event bulk updates tracing/remotes: Fix page_va[] access before counter update in trace_remote_alloc_buffer() |
||
|
Linus Torvalds
|
a6671109d6 |
- SMP-call fixes when CSD lock debugging is enabled (Chuyi Zhou)
Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmpl0OURHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1jnng/9HrimCemEFDFpbyfbqf5ucrV8FyrbIWIX HgxpXYKpOAobz2d0DYA0dn7y+HGVJr9rU7tLxeLpH+NSsT+nm/wva+2D0X4h8Lod VKNFXI1EeQ6GJ0bmRY/DBv2GKPrYfnb1gzn/HO6KE/GITWO79Uq48K/4GTE+mbR6 l++YilPqJfujYA6IlnxdexSJNZUkNbL8lDHsxBm0xM+TyG5JP+xpdHZLpU6Tf5fd l+DcTg6KriS1T+PqAWa+2BXhMhJg2BTEZmH3mU3uvqv8EDMyTUpP4X/f0JLVU/qi 24aFDCrd5zwDey58CXnOhybzpgH7Em8/1GMN5t+6eJBtPt4Hd48h7XVgJeGZje8t yxxtruQ/c5NiKYCoHPro0uMPYu6SWaz8k/h8U2dHqtg6nswVTv89V7jSno8UGsW0 W+vJcDpO3KlfHDRXLQg2E+/WRpQzD5bUeaV9/d0x/4BzokmSDNlafMNZ/bL0RUT+ I0ij4TI16RQNSMxUMTLRC9SP4n1YyH0VMGRn9goTEns2DBdl8Y+xHH+Cnk4RedwX 9MmTLvHyuKHh5VeytWlvNbQD7+L13neec/Hlhw7/sLH7+LMUJfeMM6y4roWQvDuG /5lIT/7P/ketFzgQSGVMtaUi3ZCgfT4ZCS6X6KyaSe3F654Jt0ZpdyUQ9t1Xc42U Z+QM5jJ/4gY= =6nVN -----END PGP SIGNATURE----- Merge tag 'smp-urgent-2026-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull SMP debug fixes from Ingo Molnar: - SMP-call fixes when CSD lock debugging is enabled (Chuyi Zhou) * tag 'smp-urgent-2026-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: smp: Make CSD lock acquisition atomic for debug mode smp: Avoid invalid per-CPU CSD lookup with CSD lock debug |
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Steven Rostedt
|
2c2b322acd |
tracing: perf: Fix stale head for perf syscall tracing
The code that can read the user space parameters of a system call may
enable preemption and migrate. The head of the per CPU perf events list
may be pointing to the wrong CPU event if the code migrates the task.
Reassign the head pointer if the system call event called the code that
may have caused a migration.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260724193210.03fae1d6@gandalf.local.home
Reported-by: Sashiko <>
Link: https://sashiko.dev/#/patchset/20260717173252.3431565-1-usama.arif%40linux.dev
Fixes:
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Tengda Wu
|
7720b63bce |
ftrace: Add global mutex to serialize trace_parser access
In ftrace, the trace_parser structure is allocated and initialized when a trace file is opened, and is subsequently used across write and release handlers to parse user input. The affected handler paths and their specific functions are: - Open paths: ftrace_regex_open(), ftrace_graph_open() - Write paths: ftrace_regex_write(), ftrace_graph_write() - Release paths: ftrace_regex_release(), ftrace_graph_release() If userspace opens a trace file descriptor and shares it across multiple threads, concurrent write calls will race on the parser's internal state, specifically the 'idx', 'cont', and 'buffer' fields, leading to corrupted input or undefined behavior. Fix this by adding a global mutex, parser_lock, to serialize all access to trace_parser across write and release paths, preventing concurrent corruption of parser state. Fixes: |
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Linus Torvalds
|
ae453eef92 |
BPF fixes:
- Fix tcp_bpf_sendmsg() error path mistaking a concurrently-freed sk_psock->cork for the local temporary message and freeing it again. (Chengfeng Ye) - Reject passing scalar NULL to nonnull arg of a global subprog. Previously the verifier did not account for the cases directly passing scalars to a global subprog, e.g.: 'global_func(0);' would pass even if 'global_func' argument was marked nonnull. (Amery Hung) Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRINyQBqoQUC24dy5htleuBPyPTXgUCamPsBwAKCRBtleuBPyPT Xo/uAP0YR6/9em1W/sZnss6Wkwfwd9NdmmlrJqSlt7aq+A+W7AD/V5HbigM4pJ76 CZFkKvnzhhU3dSXm/dBT1/GGJbL4pwo= =uzKM -----END PGP SIGNATURE----- Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Pull bpf fixes from Eduard Zingerman: - Fix tcp_bpf_sendmsg() error path mistaking a concurrently-freed sk_psock->cork for the local temporary message and freeing it again (Chengfeng Ye) - Reject passing scalar NULL to nonnull arg of a global subprog. Previously the verifier did not account for the cases directly passing scalars to a global subprog, e.g.: 'global_func(0);' would pass even if 'global_func' argument was marked nonnull (Amery Hung) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf, sockmap: Fix cork use-after-free in tcp_bpf_sendmsg() selftests/bpf: Test passing scalar NULL to nonnull global subprog bpf: Reject passing scalar NULL to nonnull arg of a global subprog |
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Steven Rostedt
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e091351b38 |
tracing: Delay module ref count for "enable_event" trigger
Triggers are now delayed from freeing, but can still be triggered until
after the RCU grace period has ended. The freeing of the enable_event data
is put into the private_data_free() callback, but the put of the module
refcount is done immediately.
It is possible that if a module is removed that has an event that would
enable (or disable) it is still active, it can read the data of the module
after it is removed causing a use-after-free bug.
Move the trace_event_put_ref() that releases the module into the delayed
callback so that the module can not be removed until any reference to its
events are finished.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260724132415.1b5005db@gandalf.local.home
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260724030523.19081-1-devnexen%40gmail.com
Fixes:
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David Carlier
|
7909781215 |
tracing: Fix use-after-free freeing trigger private data
Commit |
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Usama Arif
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8f76afb9b1 |
tracing: Fix context switch counter truncation
trace_user_fault_read() samples nr_context_switches_cpu() before enabling
preemption and retries the user copy if the counter changes. The helper
returns unsigned long long because rq->nr_switches is u64, but the saved
value is unsigned int.
Once a CPU has performed 2^32 context switches, assigning the counter to
cnt discards its upper bits. The comparison after the copy promotes cnt
back to unsigned long long, but the lost bits remain zero, so it reports a
change even when the task was never scheduled out. Every retry then fails
the same way until the 100-try guard warns and the user copy is abandoned.
This affects long-running systems and workloads with high context-switch
rates. A CPU switching 1,000 times per second takes about 50 days.
Store the sampled count in unsigned long long so the full value is
preserved.
Cc: stable@vger.kernel.org
Fixes:
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Masami Hiramatsu (Google)
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b4eb07bde6 |
tracing: Fix union collision of module and refcnt for dynamic events
In 'struct trace_event_call', the 'module' pointer and the 'refcnt'
atomic variable share the same memory space in a union. For dynamic
events, the union member is 'refcnt', which acts as an active
reference counter.
When a dynamic event (such as kprobe, uprobe, fprobe, eprobe, or
wprobe) has a non-zero reference count (e.g. due to active event
triggers or perf attachments), its 'call->module' evaluates to a
small non-zero integer instead of NULL.
When filtering or setting events for a specific module (e.g., writing
':mod:<module>' to 'set_event'), the code in
'__ftrace_set_clr_event_nolock()' and 'update_event_fields()' reads
'call->module' directly without checking whether the event is dynamic.
This causes the kernel to treat the small integer (refcnt) as a
'struct module' pointer, leading to a NULL/invalid pointer dereference
(Oops) when dereferencing the module name.
Fix this by ensuring that the 'TRACE_EVENT_FL_DYNAMIC' flag is checked
before treating 'call->module' as a valid pointer in these code paths.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/178425670947.84440.11344393611899824907.stgit@devnote2
Fixes:
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Steven Rostedt
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144f29e857 |
tracing: Fix mmiotrace possible NULL dereferencing of hiter->dev
If the mmio_pipe_open() fails to find a PCI device, the hiter->dev
will be assigned to NULL. The mmiotrace read() function dereferences the
hiter->dev if hiter exists.
Change the test of the read to not only check hiter being NULL, but also
the hiter->dev before dereferencing it.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260721211143.36dbd559@gandalf.local.home
Fixes:
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Amery Hung
|
289e680c89 |
bpf: Reject passing scalar NULL to nonnull arg of a global subprog
A global subprogram argument tagged __arg_nonnull is set up as a
non-nullable PTR_TO_MEM. However the verifier does not check against a
scalar NULL, leading to real NULL pointer dereference. Reject it as
well.
Fixes:
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deepakraog
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c1d87e724a |
tracing: Fix resource leak on mmiotrace trace_pipe close
The mmiotrace tracer was added May 12th 2008. At that time, resources
created in pipe_open() could not be freed because there was not
pipe_close function pointer of the tracer. The pipe_close function pointer
was added in December 7th, 2009, but the mmiotrace tracer was not updated.
mmio_pipe_open() allocates a header_iter and takes a pci_dev reference
when trace_pipe is opened. mmio_close() frees them, but it was only
wired to the tracer's .close callback.
tracing_release_pipe() invokes .pipe_close, not .close, when the
trace_pipe file is released. As a result, closing trace_pipe with the
mmiotrace tracer active leaked the header_iter allocation and left a
stale pci_dev reference.
Set .pipe_close to mmio_close, matching how function_graph wires both
callbacks to the same handler.
Note, if the trace_pipe is read to completion, it will clean up the
resources, but if one were to run:
# head -n 1 /sys/kernel/tracing/trace_pipe
VERSION 20070824
Over and over again, it would trigger a massive leak.
Cc: stable@vger.kernel.org
Fixes:
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Jackie Liu
|
655111f878 |
tracing: Propagate errors from remote event bulk updates
remote_events_dir_enable_write() ignores the return value from
trace_remote_enable_event(). If a remote rejects an event state change,
the write therefore reports success even though the affected event remains
in its previous state.
Keep trying all events, but retain and return the first error. This matches
__ftrace_set_clr_event_nolock(), which permits partial updates while
notifying userspace when an operation fails.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260715074455.3897-1-liu.yun@linux.dev
Fixes:
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Fuad Tabba
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94b83ff0c0 |
tracing/remotes: Fix page_va[] access before counter update in trace_remote_alloc_buffer()
page_va[] is annotated __counted_by(nr_page_va), so nr_page_va must
cover an index before that element is accessed. The allocation loop
writes page_va[id] while nr_page_va is still id and increments it only
afterwards, so every write is one element past the declared count.
The store is out of bounds with respect to the annotation: a build with
CONFIG_UBSAN_BOUNDS on a toolchain that honours __counted_by
(clang >= 20.1, gcc >= 15.1) flags it as an array-index overflow.
Increment nr_page_va before writing the element it now covers. A failed
allocation then leaves the slot counted but NULL; the error path frees
it with free_page(0), which is a no-op.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260713072823.2668323-1-fuad.tabba@linux.dev
Fixes:
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Chuyi Zhou
|
35551efb15 |
smp: Make CSD lock acquisition atomic for debug mode
Commit |
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Chuyi Zhou
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c58ea9adf7 |
smp: Avoid invalid per-CPU CSD lookup with CSD lock debug
Commit |
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Linus Torvalds
|
4539944e51 |
liveupdate: a fix for v7.2-rc5
* Fix validation of LIVEUPDATE_SESSION_GET_NAME ioctl argument caused by a wrong resolution of a merge conflict during the last merge window -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEeOVYVaWZL5900a/pOQOGJssO/ZEFAmpg7E4ACgkQOQOGJssO /ZHdXQf+KPPnhNyDqHgHtnsp/sd4wQ5vGVjfmAwtX7nxpxPenGSwhZ8yKShClMNM 2s0KDQmorqKK1j3MMy+xzI+MUl7uHMnHB4cpOsESrILzfqWUgo5VmEU4beCCYXXs 1JD4eKjAs+7F59g0HE75pwmqyXzrD2nq29xWlVxQCOxsTkGe+j28B/uqw0MI8CTd 66LZzyFRT/VBjyaZYSU03KN5heJsFsckYaoPCxK4bZqaiFi65bCyd/YZ7t6JgqDl PLx1fwjFpmCz6HArFfw3EnwVzkMoZ/qep4h+h+WMH3jiXUUKFHuJWpHYoXYN1C4r xuQm3Rpq3HmwR/8VHtwLTJSeNXtfBg== =KyUS -----END PGP SIGNATURE----- Merge tag 'liveupdate-fixes-2026-07-22' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux Pull liveupdate fix from Mike Rapoport: - Fix validation of LIVEUPDATE_SESSION_GET_NAME ioctl argument caused by a wrong resolution of a merge conflict during the last merge window * tag 'liveupdate-fixes-2026-07-22' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux: liveupdate: fix GET_NAME ioctl argument validation |
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Masami Hiramatsu (Google)
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f418d68d71 |
tracing/eprobe: Fix exact system name matching in eprobe_dyn_event_match()
eprobe_dyn_event_match() checks if the target event system in argv[0]
matches ep->event_system using strncmp(ep->event_system, argv[0], len).
However, if ep->event_system is longer than len (e.g. "eprobes" vs
"ep/event"), strncmp() still returns 0 because the first len characters
match.
Check that ep->event_system[len] is '\0' to ensure exact system name
matching.
Link: https://lore.kernel.org/all/178454235856.290363.14872590900774231133.stgit@devnote2/
Fixes:
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Masami Hiramatsu (Google)
|
8ce20bfba4 |
tracing/probes: Fix potential underflow in LEN_OR_ZERO macro
In __set_print_fmt(), LEN_OR_ZERO is defined as (len ? len - pos : 0).
If len is non-zero but smaller than pos, len - pos evaluates to a negative
integer. When passed as a size argument to snprintf(), this negative value
is cast to a large unsigned size_t, bypassing buffer size limits.
Ensure len > pos before subtracting to avoid integer underflow.
Link: https://lore.kernel.org/all/178454234934.290363.15247317871499514139.stgit@devnote2/
Fixes:
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Masami Hiramatsu (Google)
|
a9d6fb2840 |
tracing/probes: Prevent out-of-bounds write in __trace_probe_log_err()
If trace_probe_log.argc is 0 in __trace_probe_log_err(), the loop
constructing the command string will not execute and p will remain equal to
command. Writing to *(p - 1) will cause an out-of-bounds access before
command. This should not happen, but better to be treated.
Reject if trace_probe_log.argc is 0.
Link: https://lore.kernel.org/all/178454233992.290363.18323091580600697731.stgit@devnote2/
Fixes:
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Masami Hiramatsu (Google)
|
15f197856d |
tracing/probes: Avoid temporary buffer truncation in trace_probe_match_command_args()
In trace_probe_match_command_args(), a stack buffer buf[MAX_ARGSTR_LEN + 1]
(256 bytes) is used to format "<name>=<comm>". However, since name can
be up to 32 bytes (MAX_ARG_NAME_LEN) and comm up to 255 bytes
(MAX_ARGSTR_LEN), the formatted string can exceed 256 bytes and get
truncated by snprintf(), causing spurious argument matching failures.
Instead of formatting into a temporary buffer on stack, compare the
argument name, the '=' delimiter, and the comm expression directly.
Link: https://lore.kernel.org/all/178454233010.290363.10428767141343428804.stgit@devnote2/
Fixes:
|
||
|
Linus Torvalds
|
94515f3a7d |
BPF fixes:
- Fix a UAF in socket clone early bailout paths (Matt Bobrowski) - Reject unhashed UDP sockets on sockmap update to prevent refcount leaks (Michal Luczaj) - Account for receive queue data in FIONREAD on sockmap sockets without a verdict program (Mattia Meleleo) - Reject negative constant offsets for verifier buffer pointers (Sun Jian) - Fix for tracing of kfuncs with implicit arguments (Ihor Solodrai) Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQR0/74CM8h5+1E9pgtHLTd7Y1QvgwUCalp3/AAKCRBHLTd7Y1Qv g9J/AQCJzidAmStp1i074sZC7sC1uq+aYIvwycpMTp6hVgyP+AEAw7oKcnGkPGXs jeEDctaLtxBnPMXGAR5UaeqdNqu9ywQ= =zQgn -----END PGP SIGNATURE----- Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Pull bpf fixes from Kumar Kartikeya Dwivedi: - Fix a UAF in socket clone early bailout paths (Matt Bobrowski) - Reject unhashed UDP sockets on sockmap update to prevent refcount leaks (Michal Luczaj) - Account for receive queue data in FIONREAD on sockmap sockets without a verdict program (Mattia Meleleo) - Reject negative constant offsets for verifier buffer pointers (Sun Jian) - Fix for tracing of kfuncs with implicit arguments (Ihor Solodrai) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: selftests/bpf: Cover tracing implicit kfunc args bpf: Fix tracing of kfuncs with implicit args selftests/bpf: Cover negative buffer pointer offsets bpf: Reject negative const offsets for buffer pointers selftests/bpf: Test FIONREAD on a sockmap socket without a verdict program bpf, sockmap: Account for receive queue in FIONREAD without a verdict program selftests/bpf: Fail unbound UDP on sockmap update selftests/bpf: Adapt sockmap update error handling bpf, sockmap: Reject unhashed UDP sockets on sockmap update selftests/bpf: Ensure UDP sockets are bound bpf: Fix UAF in sock clone early bailouts |
||
|
Ihor Solodrai
|
3917b1012e |
bpf: Fix tracing of kfuncs with implicit args
A kfunc marked with KF_IMPLICIT_ARGS flag takes implicit arguments
(such as bpf_prog_aux) that the verifier injects at load time.
resolve_btfids strips those from the kfunc's BTF-visible prototype and
keeps the real kernel ABI in a counterpart _impl prototype [1].
fentry/fexit/fmod_ret/fsession programs may attach to the BPF kernel
functions, including those with implicit args. However
bpf_check_attach_target() and bpf_check_attach_btf_id_multi() extract
the struct btf_func_model from the wrong BTF prototype of the
kfunc. The btf_func_model is later read to construct the trampoline,
which then causes the injected implicit argument to be clobbered and
the kfunc dereferencing garbage.
Add btf_attach_func_proto() to resolve the real ABI prototype of the
kfunc the way the call site does: by looking up the _impl prototype
for a KF_IMPLICIT_ARGS kfunc. Use it at both attach-target model
construction sites.
To enable this, make two supporting changes:
* pass bpf_verifier_log instead of bpf_verifier_env to
find_kfunc_impl_proto(), so it can be reused from the attach path
* add btf_kfunc_check_flag() to test a flag across all of a kfunc's
hook sets, because a program attaching to a kfunc is not in the
kfunc's call-set
KF_IMPLICIT_ARGS must be consistent across the sets, so
btf_kfunc_check_flag() returns -EINVAL on inconsistency.
btf_kfunc_check_flag() reads the kfunc's flags from the target's
kfunc_set_tab. For a module BTF that table is stable only after the
module is live, so take a module reference around the read, mirroring
how the kfunc call path gates the same lookup with btf_try_get_module().
The remaining call sites of btf_distill_func_proto() are safe as
is. The BPF_TRACE_ITER case distills a registered iterator's
prototype, and bpf_struct_ops_desc_init() distills the
function-pointer members of a struct_ops type. Neither is a kfunc, and
so can't have implicit arguments.
[1] https://lore.kernel.org/all/20260120222638.3976562-1-ihor.solodrai@linux.dev/
Fixes:
|
||
|
Jackie Liu
|
4416f8a9ed |
liveupdate: fix GET_NAME ioctl argument validation
LIVEUPDATE_SESSION_GET_NAME was developed in the liveupdate/next branch while the session type validation change was carried in liveupdate-fixes. When the conflict between the two branches was resolved, the GET_NAME operation descriptor picked up the structure and last member from RETRIEVE_FD. This makes both its known size and minimum size 16 bytes rather than 72. A zero-initialized request still succeeds because luo_session_get_name() writes the full name before luo_ucmd_respond() copies the full GET_NAME response to userspace. However, copy_struct_from_user() treats the output-only name field as unknown trailing data and rejects the request with -E2BIG if any byte in that field is nonzero. Use the GET_NAME structure and its name field in the descriptor. Link: https://lore.kernel.org/all/ahWlYXNjGUbkKoHy@sirena.org.uk/ Assisted-by: Codex:gpt-5.6-sol Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org> Signed-off-by: Jackie Liu <liuyun01@kylinos.cn> Link: https://patch.msgid.link/20260716012607.22020-1-liu.yun@linux.dev Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> |
||
|
Sun Jian
|
fd4cfa8c8f |
bpf: Reject negative const offsets for buffer pointers
The verifier rejects variable offsets for PTR_TO_TP_BUFFER and PTR_TO_BUF accesses, but it currently accepts a constant negative offset produced by pointer arithmetic. Commit |
||
|
Linus Torvalds
|
3b029c035b |
cgroup: Fixes for v7.2-rc3
- A cpuset that never set its memory nodes could divide by zero when a task's mempolicy rebinds on CPU hotplug. Rebind against the effective nodes, which are always populated. - Documentation fixes for memory.stat, io.stat, and the misc and v1 RDMA controllers. -----BEGIN PGP SIGNATURE----- iIQEABYKACwWIQTfIjM1kS57o3GsC/uxYfJx3gVYGQUCalVWkg4cdGpAa2VybmVs Lm9yZwAKCRCxYfJx3gVYGet9AQD3/qE93E+PctxXa+rmRfSSjIzqqv9NUZa4THjs YOUqSAEApVSLPkhg3xHF61q9l+FuocLLY378Uf6LYGWet1SghAQ= =1Gp+ -----END PGP SIGNATURE----- Merge tag 'cgroup-for-7.2-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: - A cpuset that never set its memory nodes could divide by zero when a task's mempolicy rebinds on CPU hotplug. Rebind against the effective nodes, which are always populated - Documentation fixes for memory.stat, io.stat, and the misc and v1 RDMA controllers * tag 'cgroup-for-7.2-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: Docs/admin-guide/cgroup-v2: note blkcg_debug_stats gates io.latency stats Docs/admin-guide/cgroup-v1: document rdma.peak, rdma.events and rdma.events.local Docs/admin-guide/cgroup-v2: drop stale misc interface file count cgroup/cpuset: rebind mm mempolicy to effective_mems, not mems_allowed Docs/admin-guide/cgroup-v2: fix memory.stat doc details |
||
|
Linus Torvalds
|
f7574d3f90 |
sched_ext: Fixes for v7.2-rc3
- Lifecycle fixes for the new sub-scheduler support: two use-after-frees and an enable-failure path that left a half-initialized sub-scheduler linked. - Two dispatch-path locking bugs: a spurious scheduler abort from a migration race, and a lockdep splat from stale runqueue-lock tracking. - Callback and task-state fixes: stale scheduler-owned state on a task leaving SCX, a weight callback running after disable, and a bogus warning on core-scheduling forced idle. - On nohz_full, finite-slice tasks could miss the tick that expires their slice. Enable it when such a task is picked, with a selftest. - Smaller fixes: userspace CPU-mask helpers, ratelimited deprecation warnings, docs and a sparse annotation. -----BEGIN PGP SIGNATURE----- iIQEABYKACwWIQTfIjM1kS57o3GsC/uxYfJx3gVYGQUCalVWgw4cdGpAa2VybmVs Lm9yZwAKCRCxYfJx3gVYGTmUAP0QHX7Ae/g7yMPEB4slURpnSj/wE7hRCI5jTmay 2iIEJgD/RAhpwUUAp4Abozt0mjQMWh9UyEVjOxPCVNKaNh1XfwU= =EBCm -----END PGP SIGNATURE----- Merge tag 'sched_ext-for-7.2-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext Pull sched_ext fixes from Tejun Heo: - Lifecycle fixes for the new sub-scheduler support: two use-after-frees and an enable-failure path that left a half-initialized sub-scheduler linked. - Two dispatch-path locking bugs: a spurious scheduler abort from a migration race, and a lockdep splat from stale runqueue-lock tracking. - Callback and task-state fixes: stale scheduler-owned state on a task leaving SCX, a weight callback running after disable, and a bogus warning on core-scheduling forced idle. - On nohz_full, finite-slice tasks could miss the tick that expires their slice. Enable it when such a task is picked, with a selftest. - Smaller fixes: userspace CPU-mask helpers, ratelimited deprecation warnings, docs and a sparse annotation. * tag 'sched_ext-for-7.2-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: sched_ext: Skip ops.set_weight() for disabled tasks tools/sched_ext: scx - Fix cmask_subset(), cmask_equal() and cmask_weight() sched_ext: Fix premature ops->priv publication in scx_alloc_and_add_sched() sched_ext: Record an error on errno-only sub-enable failure selftests/sched_ext: Verify nohz_full tick behavior sched_ext: Enable tick for finite slices on nohz_full sched_ext: Preserve rq tracking across local DSQ dispatch sched_ext: Documentation: Fix ops table header reference sched_ext: Don't warn on core-sched forced idle in put_prev_task_scx() sched_ext: Pin parent scx_sched across a child sub-scheduler's lifetime sched_ext: Annotate ksyncs with __rcu in alloc/free_kick_syncs() sched_ext: Check remote rq eligibility under task's rq lock sched_ext: Reset dsq_vtime and slice when a task leaves SCX sched_ext: Avoid flooding the log with deprecation warnings |
||
|
Linus Torvalds
|
6205562c59 |
tracing fixes for 7.2:
- Free field in error path of synthetic event parse In __create_synth_event() the field was allocated but was not freed in the error path. - Fix ring_buffer_event_length() on 8 byte aligned architectures On architectures with CONFIG_HAVE_64BIT_ALIGNED_ACCESS set to y, the ring_buffer_event_length() may return the wrong size. This is because archs with that config set will always use the "big event meta header" as that is 8 bytes keeping the payload 8 bytes aligned, even when a 4 byte header could hold the size of the event. But ring_buffer_event_length() doesn't take this into account and only subtracts 4 bytes for the meta header in the length when it should have subtracted 8 bytes. - Have osnoise wait for a full rcu synchronization on unregister osnoise_unregister_instance() used to call synchronize_rcu() before freeing its copy of the instance but was switched to kfree_rcu(). The osniose tracer has code that traverses the instances that it uses, and inst is just a pointer to that instance. By using kfree_rcu() instead of synchronize_rcu(), the instance that the inst pointer is pointing to can be freed while the osnoise code is still referencing it. That is, a rmdir on an instance first unregisters the tracer. When the unregister finishes, the rmdir expects that the tracer is finished with the instance that it is using. By putting back the synchronize_rcu() in osnoise_unregister_instance() the unregistering of osnoise will now return when all the users of the instance have finished. - Remove an unused setting of "ret" in tracing_set_tracer() - Fix ring_buffer_read_page() copying events The commit that changed ring_buffer_read_page() to show dropped events from the buffer itself, split the "commit" variable between the commit value (with flags) and "size" that holds the size of the sub-buffer. A cut and paste error changed the test of the reading from checking the size of the buffer to the size of the event causing reads to only read one event at a time. - Make tracepoint_printk a static variable When the tracing sysctl knobs were move from sysctl.c to trace.c, the variable tracepoint_printk no longer needed to be global. Make it static. - Fix some typos - Fix NULL pointer dereference in func_set_flag() The flags update of the function tracer first checks if the value of the flag is the same and exits if they are, and then it checks if the current tracer is the function tracer and exits if it isn't. The problem is that these checks need to be in a reversed order, as if the tracer isn't the function tracer, then the flag being checked may not exist. Reverse the order of these checks. - Fix ufs core trace events to not dereference a pointer in TP_printk() The TP_printk() part of the TRACE_EVENT() macro is called when the user reads the "trace" file. This can be seconds, minutes, hours, days, weeks, and even months after the data was recorded into the ring buffer. Thus, saving a pointer to an object into the ring buffer and then dereferencing it from TP_printk() can cause harm as the object the pointer is pointing to may no longer exist. Fix all the trace events in ufs core to save the device name in the ring buffer instead of dereferencing the device descriptor from TP_printk(). - Prevent out-of-bound reads in glob matching of trace events The filter logic of events allows simple glob logic to add wild cards to filter on strings. But some events have fields that may not have a terminating 'nul' character. This may cause the glob matching to go beyond the string. Change the logic to always pass in the length of the field that is being matched. - Add no-rcu-check version of trace_##event##_enabled() The trace_##event##_enabled() usually wraps trace events to do extra work that is only needed when the trace event is enabled. But this can hide events that are placed in locations where RCU is not watching, and can make lockdep not see these bugs when the event is not enabled. The trace_##event##_enabled() was updated to always test to make sure RCU is watching to catch locations that may call events without RCU being active. This caused a false positive for the irq_disabled() and related events. As that use trace_irq_disabled_enabled() to force RCU to be watching when the event is enabled via the ct_irq_enter() function, calls the event, and then calls ct_irq_exit() to put RCU back to its original state. The trace_irq_disabled_enabled() should not trigger a warning when RCU is not watching because the code within its block handles the case properly. Make a __trace_##event##_enabled() version for this event to use that doesn't check RCU is watching as it handles the case when it isn't. - Fix use-after-free in user_event_mm_dup() When the enabler is removed from the link list, it is freed immediately. But it is protected via RCU and needs to be freed after an RCU grace period. Use queue_rcu_work() so that the event_mutex can also be taken as user_event_put() takes the mutex on the last reference is released. - Free type string in error path of parse_synth_field() There's an error path in parse_synth_field() where the allocated type string is not freed. - Add selftest that tests deferred event teardown - Fix leak in error path of trace_remote_alloc_buffer() If page allocation fails, the desc->nr_cpus is not incremented for the current CPU and the allocations done for it are not freed. - Fix allocation length in trace_remote_alloc_buffer() The logic to calculate the struct_len was doing a double count and setting the value too large. Calculate the size upfront to fix the error and simplify the logic. - Fix sparse CPU masks in ring_buffer_desc() If there are sparse CPUs (gaps in the numbering), the ring_buffer_desc() will fail as it tests the CPU number against the number of CPUs that are used. -----BEGIN PGP SIGNATURE----- iQJIBAABCgAyFiEEXtmkj8VMCiLR0IBM68Js21pW3nMFAmpTv/cUHHJvc3RlZHRA Z29vZG1pcy5vcmcACgkQ68Js21pW3nN80w/9HEbliUUrJVNw8QCY8BmeBEzfCRhZ 2CeDzTg+UrLMb2BtqUhA9EjQnRPawe8mPxAfpZ750SdFnCkRhbfNwYmKar3M/8iW y2Bhsvd3Hz6nRiHvKhG/1RkflgKOWLYf/TQSByKlakYLV8t4uffa0fe0N0zcnikK XPGrhrTeRDJ7s94vb1u7p7mSSp2iy4ZhfXbagk966X3I4zvseIYNn5IIzyM3IIPT M7mE60SxvgSRz0QqTJqihmqjXYSeNOQ2iU18wnvp4QfcT0IVuLKm027JnK/YpjWS ZasMNGzO1kp5uo6hkXLrMlT3LjaNEMFTGogs1m9o9auhbMf443LK8GtZ1m1rwnTG cXn1PocBevQIaXWPbnxMrSwIuN7YMUqjgX6SCxbXpDxSSuE5i/x1VmE08CjxnSm6 TdAdom9bE44FvMgaAz9+KhIUgm013c2rFDNiFroYtfkma5FqpfnfglA4/TkJvexY e2L75cR3lrDEDiXXMQDndmvxNMhppwNlAH3mOZLiaCmGyFQFHhgAaG250K2Y6a5K HtIfJkT6RQ3rWifV0E0+zlyRiOrvVCCA8WwNArWb1dTWrVU86Hr7q58jAq9p0Yrz FnhpjdE3eWoUHZ5f28AMR2k5lMG3o6mOGT55JyUVCLw+rPSG5358UIg2xZiEo22k RFlT26FFHbMW50Y= =+//w -----END PGP SIGNATURE----- Merge tag 'trace-v7.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Free field in error path of synthetic event parse In __create_synth_event() the field was allocated but was not freed in the error path - Fix ring_buffer_event_length() on 8 byte aligned architectures On architectures with CONFIG_HAVE_64BIT_ALIGNED_ACCESS set to y, the ring_buffer_event_length() may return the wrong size. This is because archs with that config set will always use the "big event meta header" as that is 8 bytes keeping the payload 8 bytes aligned, even when a 4 byte header could hold the size of the event But ring_buffer_event_length() doesn't take this into account and only subtracts 4 bytes for the meta header in the length when it should have subtracted 8 bytes - Have osnoise wait for a full rcu synchronization on unregister osnoise_unregister_instance() used to call synchronize_rcu() before freeing its copy of the instance but was switched to kfree_rcu(). The osniose tracer has code that traverses the instances that it uses, and inst is just a pointer to that instance. By using kfree_rcu() instead of synchronize_rcu(), the instance that the inst pointer is pointing to can be freed while the osnoise code is still referencing it That is, a rmdir on an instance first unregisters the tracer. When the unregister finishes, the rmdir expects that the tracer is finished with the instance that it is using. By putting back the synchronize_rcu() in osnoise_unregister_instance() the unregistering of osnoise will now return when all the users of the instance have finished - Remove an unused setting of "ret" in tracing_set_tracer() - Fix ring_buffer_read_page() copying events The commit that changed ring_buffer_read_page() to show dropped events from the buffer itself, split the "commit" variable between the commit value (with flags) and "size" that holds the size of the sub-buffer. A cut and paste error changed the test of the reading from checking the size of the buffer to the size of the event causing reads to only read one event at a time - Make tracepoint_printk a static variable When the tracing sysctl knobs were move from sysctl.c to trace.c, the variable tracepoint_printk no longer needed to be global. Make it static - Fix some typos - Fix NULL pointer dereference in func_set_flag() The flags update of the function tracer first checks if the value of the flag is the same and exits if they are, and then it checks if the current tracer is the function tracer and exits if it isn't. The problem is that these checks need to be in a reversed order, as if the tracer isn't the function tracer, then the flag being checked may not exist. Reverse the order of these checks - Fix ufs core trace events to not dereference a pointer in TP_printk() The TP_printk() part of the TRACE_EVENT() macro is called when the user reads the "trace" file. This can be seconds, minutes, hours, days, weeks, and even months after the data was recorded into the ring buffer. Thus, saving a pointer to an object into the ring buffer and then dereferencing it from TP_printk() can cause harm as the object the pointer is pointing to may no longer exist Fix all the trace events in ufs core to save the device name in the ring buffer instead of dereferencing the device descriptor from TP_printk() - Prevent out-of-bound reads in glob matching of trace events The filter logic of events allows simple glob logic to add wild cards to filter on strings. But some events have fields that may not have a terminating 'nul' character. This may cause the glob matching to go beyond the string. Change the logic to always pass in the length of the field that is being matched - Add no-rcu-check version of trace_##event##_enabled() The trace_##event##_enabled() usually wraps trace events to do extra work that is only needed when the trace event is enabled. But this can hide events that are placed in locations where RCU is not watching, and can make lockdep not see these bugs when the event is not enabled The trace_##event##_enabled() was updated to always test to make sure RCU is watching to catch locations that may call events without RCU being active This caused a false positive for the irq_disabled() and related events. As that use trace_irq_disabled_enabled() to force RCU to be watching when the event is enabled via the ct_irq_enter() function, calls the event, and then calls ct_irq_exit() to put RCU back to its original state The trace_irq_disabled_enabled() should not trigger a warning when RCU is not watching because the code within its block handles the case properly. Make a __trace_##event##_enabled() version for this event to use that doesn't check RCU is watching as it handles the case when it isn't - Fix use-after-free in user_event_mm_dup() When the enabler is removed from the link list, it is freed immediately. But it is protected via RCU and needs to be freed after an RCU grace period. Use queue_rcu_work() so that the event_mutex can also be taken as user_event_put() takes the mutex on the last reference is released - Free type string in error path of parse_synth_field() There's an error path in parse_synth_field() where the allocated type string is not freed - Add selftest that tests deferred event teardown - Fix leak in error path of trace_remote_alloc_buffer() If page allocation fails, the desc->nr_cpus is not incremented for the current CPU and the allocations done for it are not freed - Fix allocation length in trace_remote_alloc_buffer() The logic to calculate the struct_len was doing a double count and setting the value too large. Calculate the size upfront to fix the error and simplify the logic - Fix sparse CPU masks in ring_buffer_desc() If there are sparse CPUs (gaps in the numbering), the ring_buffer_desc() will fail as it tests the CPU number against the number of CPUs that are used * tag 'trace-v7.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Allow sparse CPU masks in ring_buffer_desc() tracing/remotes: Fix struct_len in trace_remote_alloc_buffer() tracing/remotes: Fix leak in trace_remote_alloc_buffer() error path selftests/user_events: Wait for deferred event teardown after unregister tracing/synthetic: Free type string on error path tracing/user_events: Fix use-after-free in user_event_mm_dup() tracing: Add a no-rcu-check version of trace_##event##_enabled() tracing: Prevent out-of-bounds read in glob matching ufs: core: tracing: Do not dereference pointers in TP_printk() tracing: Fix NULL pointer dereference in func_set_flag() samples: ftrace: Fix typos in benchmark comment tracing: Make tracepoint_printk static as not exported ring-buffer: Fix ring_buffer_read_page() copying only one event per page tracing: Remove unused ret assignment in tracing_set_tracer() tracing/osnoise: Call synchronize_rcu() when unregistering ring-buffer: Fix event length with forced 8-byte alignment tracing/synthetic: Free pending field on error path |
||
|
Linus Torvalds
|
cab9e339cf |
Misc perf events fixes:
- Fix SVM #GP on AMD CPUs that LBR but not BRS
(Sandipan Das)
- Fix UAF bug in the perf AUX code (Lee Jia Jie)
- Fix address leakage in the AMD LBR code
(Sandipan Das)
- Fix address leakage in the AMD BRS code
(Sandipan Das)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-urgent-2026-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf events fixes from Ingo Molnar:
- Fix SVM #GP on AMD CPUs that LBR but not BRS (Sandipan Das)
- Fix UAF bug in the perf AUX code (Lee Jia Jie)
- Fix address leakage in the AMD LBR code (Sandipan Das)
- Fix address leakage in the AMD BRS code (Sandipan Das)
* tag 'perf-urgent-2026-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd/brs: Fix kernel address leakage
perf/x86/amd/lbr: Fix kernel address leakage
perf/aux: Fix page UAF in map_range()
perf/x86/amd/core: Avoid enabling BRS from the SVM reload path
|
||
|
Linus Torvalds
|
767707a53e |
- Fix a subtle posix-cpu-timers vs. exec() race, which
unearthed other races in the area (Thomas Gleixner) Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmpSJ0gRHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1hyKA//W5KqLrRgXjH9cS7tF6PLo9NhbZZn5FhH jxThPvJosNyCj8UEVD+iCRjkqkNxiY9mzx3px2ZVlJg8K35ez2PeZ/zx0wvuSWlM sD7k4S3JJQ7vAE4CkYvsf91TxCWqiOMw+NLyo7MgDhwsOdgPgUAAKlCdCyoFzRK7 rAV7FQWMQag24donwPiesk8bnU4pWrooq8BoY7XVCy6aHDwwPVxrs1yPyUEikIXq AT2HiYFOu9ok6rSlJs+A2JQnmke6M6aIJ5dmUGR7gUDRAqlXesmM6jlwklzK0a4O j6lpE05ouIhZpYzQVTDxvf8cytp0+rutTX8w0lPRlqxYkaeBVEpktxfBAoqFCsoe GpK8hK0PM57W29zhnTygQib53QQAk9QBQetp0NwUjLSOu3ouhCAOC3wuoctJ4fKY oNSKGPBhHwJN5932JuxlEll/xbo+bFyHfP87tqn1SA0bgKMSNet5q7+wYE+1gcTp 9LHQnoMpjyRBjuOupnvxqeOVbN3qlNdY6MINFwxBZuKG7UwmYpTH7l72fuUM/eNr b4UHKgwv3vuQX/BfBoT1mLnzWQTltrfEywBCXHsEHUQ7KFhdRHEbnh3zVDZCT5S3 5N/RS8aFcryD/0/DhxWEhO2DBTgjDDvmOKplIPYFtikDI1dkjZ9dZ0BCI42u6wMH by25mw2rF2s= =2I60 -----END PGP SIGNATURE----- Merge tag 'timers-urgent-2026-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Ingo Molnar: - Fix a subtle posix-cpu-timers vs. exec() race, which unearthed other races in the area (Thomas Gleixner) * tag 'timers-urgent-2026-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: posix-cpu-timers: Prevent UAF caused by non-leader exec() race |
||
|
Linus Torvalds
|
bf124bae08 |
audit/stable-7.2 PR 20260710
-----BEGIN PGP SIGNATURE----- iQJIBAABCgAyFiEES0KozwfymdVUl37v6iDy2pc3iXMFAmpRNpEUHHBhdWxAcGF1 bC1tb29yZS5jb20ACgkQ6iDy2pc3iXN5+Q/+N1wsGx07LPmidKbPTx3R+yej3JCW hoLhnmPt7AXxVL671W29vkazKZ8hyQ5hzRy3wITyue9hsiXTNIwNffE1iBKkqMVA mchh38ziazJJ3h9PVWdiXdW/PoqOIAicFCUe0KJw8bV21Tdzjl+tCqVylU4j57k8 xpkGUifsK8FpkvDMzMlOfD5e4qShOqkPhacVz1OJDrW8gHV5Dh1AuTXdKz58dA1F Plu7IrtNd+CM1AQwS8ucawDB5PXnxHa708evS5bId/9fG/x5L5ZPJw6+jCPVA+Ea qUkWWalAJzOEp4jWDhvCyymtqiGhj9rFAydxCy32IAsF7TLTDCV8E+6Iq78wGtjg Oep+Tn9wOqV5QMILqlZ0zQxeDWnQWA0MzVRqIOFAvMrpurPLUbYZLFbUyNWouGBD cfU6O+AhADTmfkFfxxTFLsm0RQCEdnF1XeZEreXgwFuuF/A7SybmB2WTWE5wcmbu Riks3O9NHK620vCLf+wNpDc7+BkNmfBBhLUsyk0NDzEsIpViWS24stumBAP7+Fge 0KnWaB+vOD8IVub1YGgrxTNf3DfK6p8CLgwGYZMBjYFczJF8gCYXTfKlqmRVpXzw 20WaBbriMeMKgC5azD3aPqCg+/vgfBdCcEHSXAIS2KZivMQqYaodlFtTUowoDKng sn2hwA3SKfZ4aGw= =wY2k -----END PGP SIGNATURE----- Merge tag 'audit-pr-20260710' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit fixes from Paul Moore: "Two relatively small audit patches to fix potential data races with the main audit backlog queue as well as possible integer overflows when logging data as hex strings" * tag 'audit-pr-20260710' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: fix potential integer overflow in audit_log_n_hex() audit: Fix data races of skb_queue_len() readers on audit_queue |
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Vincent Donnefort
|
601ddaceb8 |
ring-buffer: Allow sparse CPU masks in ring_buffer_desc()
No user currently relies on sparse CPU masks, but the descriptor logic already
supports them via linear fallback. Remove the arbitrary limitation.
Link: https://patch.msgid.link/20260709160017.1729517-4-vdonnefort@google.com
Fixes:
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Vincent Donnefort
|
d471d4f86e |
tracing/remotes: Fix struct_len in trace_remote_alloc_buffer()
Pre-calculate desc->struct_len up-front in trace_remote_alloc_buffer()
with trace_buffer_desc_size() to fix double-counting.
While at it, use the accessor __first_ring_buffer_desc().
Link: https://patch.msgid.link/20260709160017.1729517-3-vdonnefort@google.com
Fixes:
|
||
|
Vincent Donnefort
|
ec082d0b97 |
tracing/remotes: Fix leak in trace_remote_alloc_buffer() error path
If page allocation fails in trace_remote_alloc_buffer(), desc->nr_cpus
is not yet incremented for the current CPU. As a consequence, on error,
half-allocated rb_desc will not be freed in trace_remote_free_buffer().
Increment desc->nr_cpus as soon as the first allocation for the current
CPU has succeeded.
Link: https://patch.msgid.link/20260709160017.1729517-2-vdonnefort@google.com
Fixes:
|
||
|
Kuba Piecuch
|
0e2f4ab68a |
sched_ext: Skip ops.set_weight() for disabled tasks
When switching a task's sched_class away from sched_ext, we get the
following sequence of events in __sched_setscheduler():
sched_change_begin()
switched_from_scx()
scx_disable_task(p)
ops.disable(p)
__setscheduler_params()
set_load_weight()
reweight_task_scx(p)
ops.set_weight(p)
p->sched_class = next_class;
sched_change_end()
...
Notably, ops.set_weight() is called _after_ ops.disable().
This violates the expected semantics of the callbacks, the expectation
being that ops.disable() can only be followed by ops.exit_task() or
ops.enable().
Skipping the weight adjustment for disabled tasks should be harmless
since the weight will be recalculated in scx_enable_task() if the task
ever rejoins SCX.
Fixes:
|
||
|
Lee Jia Jie
|
5948aaf64f |
perf/aux: Fix page UAF in map_range()
map_range() reads rb->aux_pages[], rb->aux_nr_pages and rb->aux_pgoff via
perf_mmap_to_page() while holding only event->mmap_mutex. Those fields are
serialized by rb->aux_mutex, and mmap_mutex is per event.
Thus, two events sharing one rb via PERF_EVENT_IOC_SET_OUTPUT can race
rb_alloc_aux() with map_range(), leading to a page-UAF scenario as follows:
CPU 0 CPU 1
===== =====
rb_alloc_aux() map_range()
[1]: allocate rb->aux_pages[0]
[2]: rb->aux_nr_pages++
[3]: perf_mmap_to_page()
returns rb->aux_pages[0]
[4]: map it as VM_PFNMAP
[5]: rb->aux_pgoff = 1
munmap the page
[6]: free rb->aux_pages[0]
Pages mapped as VM_PFNMAP have no refcount protection, so CPU 1 holds a
mapping to a freed physical frame.
Fix this by taking rb->aux_mutex across the page walk in map_range().
Fixes:
|
||
|
Tejun Heo
|
49b3378a75 |
sched_ext: Fix premature ops->priv publication in scx_alloc_and_add_sched()
scx_alloc_and_add_sched() publishes @sch through ops->priv before allocating
the cgroup path. If that allocation fails, the unwind path clears ops->priv
and frees @sch immediately. scx_prog_sched() callers can dereference
ops->priv from RCU context the moment it is set, so freeing without a grace
period can use-after-free a concurrent kfunc caller.
Move the publication below the cgroup path allocation so that every failure
path after publication frees @sch through kobject_put(), whose release path
defers the freeing by a grace period.
Fixes:
|
||
|
Tejun Heo
|
db4e9defd2 |
sched_ext: Record an error on errno-only sub-enable failure
scx_sub_enable_workfn() has several failure paths that only return an errno
(e.g. -ENOMEM from an allocation) and jump to err_disable without calling
scx_error(). scx_flush_disable_work() runs the disable, and thus ops.exit(),
only when an error has been recorded, so an errno-only failure leaves the
half-initialized sub-scheduler linked.
Record an error at the err_disable sink so every errno-only failure runs the
disable path.
Fixes:
|
||
|
Andrea Righi
|
4ec10f38ff |
sched_ext: Enable tick for finite slices on nohz_full
set_next_task_scx() updates the tick dependency before __schedule()
updates rq->curr. When switching from a non-EXT task, such as idle, to
an EXT task with a finite slice, sched_update_tick_dependency() checks
the outgoing task and can allow the tick to remain stopped.
The dependency can also be lost without a slice-type transition. After a
finite-slice task leaves the CPU idle, the enqueue path can clear the
dependency against the idle rq->curr. SCX_RQ_CAN_STOP_TICK still records
a finite slice, so another finite task skips the transition block and
can run without the ticks needed to expire its slice.
The reverse mismatch can also happen when the last finite-slice EXT task
is dequeued: sub_nr_running() updates the dependency before rq->curr
changes, so the outgoing task state can keep the dependency set after
the CPU goes idle.
Fix this by unconditionally enabling the scheduler tick whenever a
finite-slice EXT task is selected on a nohz_full CPU. Moreover, when the
last runnable EXT task leaves, ignore the outgoing EXT slice state so
the generic scheduler can correctly re-evaluate and clear the tick
dependency.
Fixes:
|
||
|
Ricardo Robaina
|
65dfde57d1 |
audit: fix potential integer overflow in audit_log_n_hex()
The function calculates new_len as len << 1 for hex encoding. This
has two overflow risks: the shift itself can overflow when len is
large, and the result can be truncated when assigned to new_len
(declared as int) from the size_t calculation.
Fix by using check_shl_overflow() to catch shift overflow and
changing new_len and loop counter i to size_t to prevent truncation.
Cc: stable@vger.kernel.org
Fixes:
|
||
|
Andrea Righi
|
18d62044cd |
sched_ext: Preserve rq tracking across local DSQ dispatch
dispatch_to_local_dsq() can run from scx_bpf_dsq_move_to_local() while
ops.dispatch() has recorded the current rq. Moving a task to a local DSQ
may switch to the source or destination rq before synchronously invoking
ops.dequeue() through the following path:
SCX_CALL_OP(dispatch, rq)
ops.dispatch()
scx_bpf_dsq_move_to_local()
scx_flush_dispatch_buf()
finish_dispatch()
dispatch_to_local_dsq()
scx_dispatch_enqueue()
local_dsq_post_enq()
call_task_dequeue()
SCX_CALL_OP_TASK(dequeue, locked_rq, ...)
The nested callback saves the recorded rq and restores it on return. If
the rq tracking does not follow the lock switch, update_locked_rq() can
trigger the following lockdep assertion while restoring an rq which is
no longer held:
WARNING: kernel/sched/sched.h:1641 at call_task_dequeue+0x160/0x170
Call Trace:
scx_dispatch_enqueue+0x2b0/0x460
dispatch_to_local_dsq+0x138/0x230
scx_flush_dispatch_buf+0x1af/0x220
scx_bpf_dsq_move_to_local___v2+0xe2/0x1c0
bpf__sched_ext_ops_dispatch+0x4b/0xa7
do_pick_task_scx+0x3b6/0x910
__pick_next_task+0x105/0x1f0
__schedule+0x3e7/0x1980
Introduce switch_rq_lock() to update the tracking state together with
each rq lock handoff. Use it in dispatch_to_local_dsq(),
move_remote_task_to_local_dsq() and the in-balance paths of
scx_dsq_move(), ensuring that scx_locked_rq() consistently refers to the
rq whose lock is actually held throughout the lock dance.
Fixes:
|
||
|
Yu Peng
|
05074bb90a |
tracing/synthetic: Free type string on error path
parse_synth_field() builds a "__data_loc ..." type string before assigning it to field->type. If the seq_buf check fails, the common cleanup cannot free the temporary string. Free it before leaving. Link: https://patch.msgid.link/20260603062533.1096320-2-pengyu@kylinos.cn Signed-off-by: Yu Peng <pengyu@kylinos.cn> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> |
||
|
Michael Bommarito
|
50fd6dd755 |
tracing/user_events: Fix use-after-free in user_event_mm_dup()
user_event_mm_dup() walks the parent mm's enabler list locklessly under
rcu_read_lock() during fork() (from copy_process()); it does not take
event_mutex:
rcu_read_lock();
list_for_each_entry_rcu(enabler, &old_mm->enablers, mm_enablers_link)
enabler->event = user_event_get(orig->event);
user_event_enabler_destroy() removes an enabler from that list with
list_del_rcu() and then, without waiting for a grace period, drops the
enabler's user_event reference with user_event_put() and frees the enabler
with kfree(). A reader that loaded the enabler before the list_del_rcu()
can still be walking it, which leads to two use-after-frees:
- kfree(enabler) frees the enabler while that reader dereferences
enabler->event.
- user_event_put() may drop the last reference to the user_event, which
is then freed (via delayed_destroy_user_event() on a work queue), while
the same reader does user_event_get(orig->event) on it.
Both are reachable by an unprivileged task that can open user_events_data:
one multithreaded process that registers an enabler and then concurrently
unregisters it and calls fork() triggers the race. KASAN reports a
slab-use-after-free in user_event_mm_dup() during clone(), with a
"refcount_t: addition on 0" warning when the user_event is freed.
The enabler use-after-free was found first; the user_event one was reported
by XIAO WU, and the earlier enabler-only fix did not address it.
Defer both the user_event_put() and the kfree(enabler) to a work item
queued with queue_rcu_work(), so they run only after an RCU grace period,
once all readers walking the enabler list have finished. The put must run
in process context because user_event_put() takes event_mutex on the last
reference, so a work queue is used rather than call_rcu(). The now-unlocked
put lets the locked argument of user_event_enabler_destroy() be removed;
all callers are updated.
Fixes:
|
||
|
Steven Rostedt
|
1e67bb60bb |
tracing: Add a no-rcu-check version of trace_##event##_enabled()
Tracepoints require that RCU is watching. To prevent them from being used in places that RCU is not watching, the trace_##event() macro always calls rcu_is_watching() even when the event is not enabled and warns if RCU is not watching. This is to make sure a warning is triggered even if the tracepoint is never enabled (as it is only a bug when it is). It was noticed that tracepoints could be hidden within trace_#event#_enabled() calls, which are used to do extra work for the tracepoint only if the tracepoint is enabled. But this also can hide the fact that a tracepoint is placed in a location that can be called when RCU is not watching. Commit |
||
|
Huihui Huang
|
0a6070839b |
tracing: Prevent out-of-bounds read in glob matching
String event fields are not necessarily NUL-terminated, so the filter
predicate functions (filter_pred_string(), filter_pred_strloc() and
filter_pred_strrelloc()) pass the field length to the regex match
callbacks, and the length-aware matchers honour it.
regex_match_glob() was the exception: it ignored the length and called
glob_match(), which scans the string until it hits a NUL byte. Some
string fields are not NUL-terminated. One example is the dynamic char
array of the xfs_* namespace tracepoints, which is copied without a
trailing NUL. For such a field, glob matching reads past the end of
the event field, causing a KASAN slab-out-of-bounds read in
glob_match(), reached via regex_match_glob() and filter_match_preds()
from the xfs_lookup tracepoint.
Add a length-bounded glob_match_len() and use it from regex_match_glob()
so glob matching always stops at the field boundary. The matching loop
is factored into a shared helper so glob_match() keeps its behaviour.
Fixes:
|
||
|
Yuanhe Shu
|
c3e9460467 |
tracing: Fix NULL pointer dereference in func_set_flag()
func_set_flag() dereferences tr->current_trace_flags before verifying
that the current tracer is actually the function tracer. When the active
tracer has been switched away from "function" (e.g., to "wakeup_rt"),
tr->current_trace_flags can be NULL, leading to a NULL pointer
dereference and kernel crash.
The call chain that triggers this is:
trace_options_write()
-> __set_tracer_option()
-> trace->set_flag() /* func_set_flag */
In func_set_flag(), the first operation is:
if (!!set == !!(tr->current_trace_flags->val & bit))
This dereferences tr->current_trace_flags unconditionally. The safety
check that guards against a non-function tracer:
if (tr->current_trace != &function_trace)
return 0;
is placed *after* the dereference, which is too late.
This was observed with the following crash dump:
BUG: unable to handle page fault at 0000000000000000
RIP: func_set_flag+0xd
Call Trace:
__set_tracer_option+0x27
trace_options_write+0x75
vfs_write+0x12a
ksys_write+0x66
do_syscall_64+0x5b
RIP: ffffffff914c973d RSP: ff67ec88b01dfdf0 RFLAGS: 00010202
RAX: 0000000000000000 RBX: ff3a826e80354580 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffffff93918080
The disassembly confirms the fault:
func_set_flag+0: mov 0x1f08(%rdi), %rax ; RAX = tr->current_trace_flags = NULL
func_set_flag+13: mov (%rax), %eax ; page fault: dereference NULL
At the time of the crash:
tr->current_trace_flags = 0x0 (NULL)
tr->current_trace = wakeup_rt_tracer (not function_trace)
The scenario is that a process opens a function tracer option file (such
as "func_stack_trace"), then the current tracer is switched to another
tracer (e.g., "wakeup_rt"), which sets current_trace_flags to NULL. When
the process subsequently writes to the option file, func_set_flag() is
invoked and crashes on the NULL dereference.
Fix this by moving the current_trace check before the
current_trace_flags dereference, so that func_set_flag() returns early
when the function tracer is not active.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260624061715.1445655-1-xiangzao@linux.alibaba.com
Fixes:
|
||
|
Ben Dooks
|
d5c6785f94 |
tracing: Make tracepoint_printk static as not exported
The tracepoint_printk symbol is not exported, so make it
static to remove the following sparse warning:
kernel/trace/trace.c:90:5: warning: symbol 'tracepoint_printk' was not declared. Should it be static?
Fixes:
|
||
|
David Carlier
|
af05b4e062 |
ring-buffer: Fix ring_buffer_read_page() copying only one event per page
Commit |
||
|
Farhad Alemi
|
b983c56426 |
cgroup/cpuset: rebind mm mempolicy to effective_mems, not mems_allowed
Creating a child cpuset where cpuset.mems is never set leads to a div/0
when a VMA mempolicy with MPOL_F_RELATIVE_NODES rebinds in response to a
CPU hotplug event.
Reproduction steps:
1) Create a cgroup w/ cpuset controls (do not set cpuset.mems)
2) Move the task into the child cpuset
3) Create a VMA mempolicy for that task with MPOL_F_RELATIVE_NODES
4) unplug and hotplug a cpu
echo 0 > /sys/devices/system/cpu/cpu1/online
echo 1 > /sys/devices/system/cpu/cpu1/online
5) mempolicy rebind does a div/0 in mpol_relative_nodemask on the
call to __nodes_fold()
The cpuset code passes (cs->mems_allowed) which is not guaranteed to have
nodes to the rebind routine. Use cs->effective_mems instead, which is
guaranteed to have a non-empty nodemask once we reach that code path.
Link: https://lore.kernel.org/all/CA+0ovCiEz6SP_sn3kN4Tb+_oC=eHMXy_Ffj=usV3wREdQrUtww@mail.gmail.com/
Fixes:
|
||
|
Wayen.Yan
|
a20b08de86 |
tracing: Remove unused ret assignment in tracing_set_tracer()
In tracing_set_tracer(), the assignment 'ret = 0' following the __tracing_resize_ring_buffer() error check is a dead store. After this point, all subsequent code paths either return with a constant value (-EINVAL, 0, -EBUSY) or reassign ret before reading it (tracing_arm_snapshot_locked, tracer_init). Remove the unnecessary assignment. No functional change. Link: https://patch.msgid.link/6a2a37c4.f0a9eb5a.2fc603.7724@mx.google.com Signed-off-by: Wayen.Yan <win847@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> |