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| author | Masami Hiramatsu <mhiramat@kernel.org> | 2021-09-14 17:42:02 +0300 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2021-10-01 04:24:07 +0300 |
| commit | 7391dd19027cec4e0edf81b7c27079ae0ecd2d6b (patch) | |
| tree | 5dbbd94c3d3a40026bcfe25d7687ed7e48db0808 | |
| parent | c1f76fe58f6983205ad14045dbc303416d5e990a (diff) | |
| download | linux-7391dd19027cec4e0edf81b7c27079ae0ecd2d6b.tar.xz | |
arm: kprobes: Make space for instruction pointer on stack
Since arm's __kretprobe_trampoline() saves partial 'pt_regs' on the
stack, 'regs->ARM_pc' (instruction pointer) is not accessible from
the kretprobe handler. This means if instruction_pointer_set() is
used from kretprobe handler, it will break the data on the stack.
Make space for instruction pointer (ARM_pc) on the stack in the
__kretprobe_trampoline() for fixing this problem.
Link: https://lkml.kernel.org/r/163163052262.489837.10327621053231461255.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| -rw-r--r-- | arch/arm/probes/kprobes/core.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/arm/probes/kprobes/core.c b/arch/arm/probes/kprobes/core.c index 67ce7eb8f285..95f23b47ba27 100644 --- a/arch/arm/probes/kprobes/core.c +++ b/arch/arm/probes/kprobes/core.c @@ -376,11 +376,13 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, void __naked __kprobes __kretprobe_trampoline(void) { __asm__ __volatile__ ( + "sub sp, sp, #16 \n\t" "stmdb sp!, {r0 - r11} \n\t" "mov r0, sp \n\t" "bl trampoline_handler \n\t" "mov lr, r0 \n\t" "ldmia sp!, {r0 - r11} \n\t" + "add sp, sp, #16 \n\t" #ifdef CONFIG_THUMB2_KERNEL "bx lr \n\t" #else |