linux.git/kernel/kprobes.c, branch v6.18.21

kprobes: Remove unneeded warnings from __arm_kprobe_ftrace()

2026-03-19T15:08:44+00:00

commit 5ef268cb7a0aac55521fd9881f1939fa94a8988e upstream.

Remove unneeded warnings for handled errors from __arm_kprobe_ftrace()
because all caller handled the error correctly.

Link: https://lore.kernel.org/all/177261531182.1312989.8737778408503961141.stgit@mhiramat.tok.corp.google.com/

Reported-by: Zw Tang 
Closes: https://lore.kernel.org/all/CAPHJ_V+J6YDb_wX2nhXU6kh466Dt_nyDSas-1i_Y8s7tqY-Mzw@mail.gmail.com/
Fixes: 9c89bb8e3272 ("kprobes: treewide: Cleanup the error messages for kprobes")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) 
Signed-off-by: Greg Kroah-Hartman

kprobes: avoid crash when rmmod/insmod after ftrace killed

2026-03-19T15:08:29+00:00

commit e113f0b46d19626ec15388bcb91432c9a4fd6261 upstream.

After we hit ftrace is killed by some errors, the kernel crash if
we remove modules in which kprobe probes.

BUG: unable to handle page fault for address: fffffbfff805000d
PGD 817fcc067 P4D 817fcc067 PUD 817fc8067 PMD 101555067 PTE 0
Oops: Oops: 0000 [#1] SMP KASAN PTI
CPU: 4 UID: 0 PID: 2012 Comm: rmmod Tainted: G        W  OE
Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
RIP: 0010:kprobes_module_callback+0x89/0x790
RSP: 0018:ffff88812e157d30 EFLAGS: 00010a02
RAX: 1ffffffff805000d RBX: dffffc0000000000 RCX: ffffffff86a8de90
RDX: ffffed1025c2af9b RSI: 0000000000000008 RDI: ffffffffc0280068
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1025c2af9a
R10: ffff88812e157cd7 R11: 205d323130325420 R12: 0000000000000002
R13: ffffffffc0290488 R14: 0000000000000002 R15: ffffffffc0280040
FS:  00007fbc450dd740(0000) GS:ffff888420331000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffbfff805000d CR3: 000000010f624000 CR4: 00000000000006f0
Call Trace:
 
 notifier_call_chain+0xc6/0x280
 blocking_notifier_call_chain+0x60/0x90
 __do_sys_delete_module.constprop.0+0x32a/0x4e0
 do_syscall_64+0x5d/0xfa0
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

This is because the kprobe on ftrace does not correctly handles
the kprobe_ftrace_disabled flag set by ftrace_kill().

To prevent this error, check kprobe_ftrace_disabled in
__disarm_kprobe_ftrace() and skip all ftrace related operations.

Link: https://lore.kernel.org/all/176473947565.1727781.13110060700668331950.stgit@mhiramat.tok.corp.google.com/

Reported-by: Ye Bin 
Closes: https://lore.kernel.org/all/20251125020536.2484381-1-yebin@huaweicloud.com/
Fixes: ae6aa16fdc16 ("kprobes: introduce ftrace based optimization")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) 
Acked-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

kprobes: Add missing kerneldoc for __get_insn_slot

2025-07-15T09:45:34+00:00

Add kerneldoc for '__get_insn_slot' function to fix W=1 warnings:

  kernel/kprobes.c:141 function parameter 'c' not described in '__get_insn_slot'

Link: https://lore.kernel.org/all/20250704143817707TOCcfTRWsO5OAbQ2eYoU9@zte.com.cn/

Signed-off-by: Peng Jiang 
Signed-off-by: Masami Hiramatsu (Google)

kprobes: Use RCU in all users of __module_text_address().

2025-03-10T10:54:46+00:00

__module_text_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_text_address()
with RCU.

Cc: David S. Miller 
Cc: Anil S Keshavamurthy 
Cc: Masami Hiramatsu 
Cc: Naveen N Rao 
Cc: linux-trace-kernel@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior 
Acked-by: Peter Zijlstra (Intel) 
Link: https://lore.kernel.org/r/20250129084925.9ppBjGLC@linutronix.de
Signed-off-by: Petr Pavlu

treewide: const qualify ctl_tables where applicable

2025-01-28T12:48:37+00:00

Add the const qualifier to all the ctl_tables in the tree except for
watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls,
loadpin_sysctl_table and the ones calling register_net_sysctl (./net,
drivers/inifiniband dirs). These are special cases as they use a
registration function with a non-const qualified ctl_table argument or
modify the arrays before passing them on to the registration function.

Constifying ctl_table structs will prevent the modification of
proc_handler function pointers as the arrays would reside in .rodata.
This is made possible after commit 78eb4ea25cd5 ("sysctl: treewide:
constify the ctl_table argument of proc_handlers") constified all the
proc_handlers.

Created this by running an spatch followed by a sed command:
Spatch:
    virtual patch

    @
    depends on !(file in "net")
    disable optional_qualifier
    @

    identifier table_name != {
      watchdog_hardlockup_sysctl,
      iwcm_ctl_table,
      ucma_ctl_table,
      memory_allocation_profiling_sysctls,
      loadpin_sysctl_table
    };
    @@

    + const
    struct ctl_table table_name [] = { ... };

sed:
    sed --in-place \
      -e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \
      kernel/utsname_sysctl.c

Reviewed-by: Song Liu 
Acked-by: Steven Rostedt (Google)  # for kernel/trace/
Reviewed-by: Martin K. Petersen  # SCSI
Reviewed-by: Darrick J. Wong  # xfs
Acked-by: Jani Nikula 
Acked-by: Corey Minyard 
Acked-by: Wei Liu 
Acked-by: Thomas Gleixner 
Reviewed-by: Bill O'Donnell 
Acked-by: Baoquan He 
Acked-by: Ashutosh Dixit 
Acked-by: Anna Schumaker 
Signed-off-by: Joel Granados

kprobes: Remove remaining gotos

2025-01-10T00:00:13+00:00

Remove remaining gotos from kprobes.c to clean up the code.
This does not use cleanup macros, but changes code flow for avoiding
gotos.

Link: https://lore.kernel.org/all/173371212474.480397.5684523564137819115.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google)

kprobes: Remove unneeded goto

2025-01-10T00:00:13+00:00

Remove unneeded gotos. Since the labels referred by these gotos have
only one reference for each, we can replace those gotos with the
referred code.

Link: https://lore.kernel.org/all/173371211203.480397.13988907319659165160.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google)

kprobes: Use guard for rcu_read_lock

2025-01-10T00:00:13+00:00

Use guard(rcu) for rcu_read_lock so that it can remove unneeded
gotos and make it more structured.

Link: https://lore.kernel.org/all/173371209846.480397.3852648910271029695.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google)

kprobes: Use guard() for external locks

2025-01-10T00:00:13+00:00

Use guard() for text_mutex, cpu_read_lock, and jump_label_lock in
the kprobes.

Link: https://lore.kernel.org/all/173371208663.480397.7535769878667655223.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google)

kprobes: Adopt guard() and scoped_guard()

2025-01-10T00:00:12+00:00

Use guard() or scoped_guard() for critical sections rather than
discrete lock/unlock pairs.

Link: https://lore.kernel.org/all/173289887835.73724.608223217359025939.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google)