summaryrefslogtreecommitdiff
path: root/kernel/trace
diff options
context:
space:
mode:
authorPuranjay Mohan <puranjay@kernel.org>2025-01-15 10:36:47 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2025-02-08 09:57:33 +0100
commit78b97783496b454435639937db3303e900a24d3f (patch)
treee1053c6e34df3c208d2da7b3a4f0bd1452cf1b1b /kernel/trace
parentee46db2c8f99144abff0119cde50afac329b6f1b (diff)
downloadlinux-78b97783496b454435639937db3303e900a24d3f.tar.gz
linux-78b97783496b454435639937db3303e900a24d3f.tar.bz2
linux-78b97783496b454435639937db3303e900a24d3f.zip
bpf: Send signals asynchronously if !preemptible
[ Upstream commit 87c544108b612512b254c8f79aa5c0a8546e2cc4 ] BPF programs can execute in all kinds of contexts and when a program running in a non-preemptible context uses the bpf_send_signal() kfunc, it will cause issues because this kfunc can sleep. Change `irqs_disabled()` to `!preemptible()`. Reported-by: syzbot+97da3d7e0112d59971de@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/67486b09.050a0220.253251.0084.GAE@google.com/ Fixes: 1bc7896e9ef4 ("bpf: Fix deadlock with rq_lock in bpf_send_signal()") Signed-off-by: Puranjay Mohan <puranjay@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20250115103647.38487-1-puranjay@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel/trace')
-rw-r--r--kernel/trace/bpf_trace.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index b5cf605fb0e6..449efaaa387a 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -833,7 +833,7 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type)
if (unlikely(is_global_init(current)))
return -EPERM;
- if (irqs_disabled()) {
+ if (!preemptible()) {
/* Do an early check on signal validity. Otherwise,
* the error is lost in deferred irq_work.
*/