rethook: use preempt_{disable, enable}_notrace in rethook_trampoline_handler
authorZe Gao <zegao2021@gmail.com>
Wed, 17 May 2023 03:45:06 +0000 (11:45 +0800)
committerMasami Hiramatsu (Google) <mhiramat@kernel.org>
Wed, 17 May 2023 22:08:01 +0000 (07:08 +0900)
This patch replaces preempt_{disable, enable} with its corresponding
notrace version in rethook_trampoline_handler so no worries about stack
recursion or overflow introduced by preempt_count_{add, sub} under
fprobe + rethook context.

Link: https://lore.kernel.org/all/20230517034510.15639-2-zegao@tencent.com/
Fixes: 54ecbe6f1ed5 ("rethook: Add a generic return hook")
Signed-off-by: Ze Gao <zegao@tencent.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
kernel/trace/rethook.c

index 32c3dfdb4d6a74b9bba4dffb57914f9d71e5a591..60f6cb2b486bf466227ca2ac68070349e07556e7 100644 (file)
@@ -288,7 +288,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs,
         * These loops must be protected from rethook_free_rcu() because those
         * are accessing 'rhn->rethook'.
         */
-       preempt_disable();
+       preempt_disable_notrace();
 
        /*
         * Run the handler on the shadow stack. Do not unlink the list here because
@@ -321,7 +321,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs,
                first = first->next;
                rethook_recycle(rhn);
        }
-       preempt_enable();
+       preempt_enable_notrace();
 
        return correct_ret_addr;
 }