x86/traps: Mark do_int3() NOKPROBE_SYMBOL

Li Huafei · suryasaimadhu · commit a365a65f9ca1 · 2022-03-11T19:19:30.000+01:00
Since kprobe_int3_handler() is called in do_int3(), probing do_int3() can cause a breakpoint recursion and crash the kernel. Therefore, do_int3() should be marked as NOKPROBE_SYMBOL. Fixes: 21e2829 ("x86/traps: Split int3 handler up") Signed-off-by: Li Huafei <lihuafei1@huawei.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220310120915.63349-1-lihuafei1@huawei.com
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
@@ -659,6 +659,7 @@ static bool do_int3(struct pt_regs *regs)
 
 	return res == NOTIFY_STOP;
 }
+NOKPROBE_SYMBOL(do_int3);
 
 static void do_int3_user(struct pt_regs *regs)
 {

Original file line number	Diff line number	Diff line change
`@@ -659,6 +659,7 @@ static bool do_int3(struct pt_regs *regs)`
`659`	`659`
`660`	`660`	`return res == NOTIFY_STOP;`
`661`	`661`	`}`
	`662`	`+NOKPROBE_SYMBOL(do_int3);`
`662`	`663`
`663`	`664`	`static void do_int3_user(struct pt_regs *regs)`
`664`	`665`	`{`