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Miller" Cc: JP Kobryn , linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, Luigi Rizzo Content-Type: text/plain; charset="UTF-8" In unregister_kretprobes(), rps[i]->rph can be NULL e.g. when called after kretprobe failed registration. Under !CONFIG_KRETPROBE_ON_RETHOOK, the unconditional access to rps[i]->rph->rp, causes a kernel panic due to NULL pointer dereference. Add a NULL check for rps[i]->rph before invoking rcu_assign_pointer(). Fixes: d839a656d0f3 ("kprobes: consistent rcu api usage for kretprobe holder") Signed-off-by: Luigi Rizzo --- kernel/kprobes.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index bfc89083daa93..5dd4786c455de 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2359,7 +2359,8 @@ void unregister_kretprobes(struct kretprobe **rps, int num) #ifdef CONFIG_KRETPROBE_ON_RETHOOK rethook_free(rps[i]->rh); #else - rcu_assign_pointer(rps[i]->rph->rp, NULL); + if (rps[i]->rph) + rcu_assign_pointer(rps[i]->rph->rp, NULL); #endif } -- 2.48.1.500.g5897711438-goog