From: Artem Savkov Date: Wed, 25 Jul 2018 14:20:38 +0000 (+0200) Subject: tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=86428ec165ee9c25618794b442827ab78b3da087;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure commit 57ea2a34adf40f3a6e88409aafcf803b8945619a upstream. If enable_trace_kprobe fails to enable the probe in enable_k(ret)probe it returns an error, but does not unset the tp flags it set previously. This results in a probe being considered enabled and failures like being unable to remove the probe through kprobe_events file since probes_open() expects every probe to be disabled. Link: http://lkml.kernel.org/r/20180725102826.8300-1-asavkov@redhat.com Link: http://lkml.kernel.org/r/20180725142038.4765-1-asavkov@redhat.com Cc: Ingo Molnar Cc: stable@vger.kernel.org Fixes: 41a7dd420c57 ("tracing/kprobes: Support ftrace_event_file base multibuffer") Acked-by: Masami Hiramatsu Reviewed-by: Josh Poimboeuf Signed-off-by: Artem Savkov Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index f8d3bd974bcc..474ada34ef26 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -376,11 +376,10 @@ static struct trace_kprobe *find_trace_kprobe(const char *event, static int enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) { + struct event_file_link *link; int ret = 0; if (file) { - struct event_file_link *link; - link = kmalloc(sizeof(*link), GFP_KERNEL); if (!link) { ret = -ENOMEM; @@ -400,6 +399,16 @@ enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) else ret = enable_kprobe(&tk->rp.kp); } + + if (ret) { + if (file) { + list_del_rcu(&link->list); + kfree(link); + tk->tp.flags &= ~TP_FLAG_TRACE; + } else { + tk->tp.flags &= ~TP_FLAG_PROFILE; + } + } out: return ret; }