diff options
| author | Di Shen <di.shen@unisoc.com> | 2025-05-20 13:49:43 +0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2025-05-22 07:49:32 -0700 |
| commit | 4e2e6841ff761cc15a54e8bebcf35d7325ec78a2 (patch) | |
| tree | 78095837215a39e22fa8d1ef43903393dc752437 | |
| parent | 25b6d5def6f8d3081f69c8b73cb934942c11e63a (diff) | |
bpf: Revert "bpf: remove unnecessary rcu_read_{lock,unlock}() in multi-uprobe attach logic"
This reverts commit 4a8f635a6054.
Althought get_pid_task() internally already calls rcu_read_lock() and
rcu_read_unlock(), the find_vpid() was not.
The documentation for find_vpid() clearly states:
"Must be called with the tasklist_lock or rcu_read_lock() held."
Add proper rcu_read_lock/unlock() to protect the find_vpid().
Fixes: 4a8f635a6054 ("bpf: remove unnecessary rcu_read_{lock,unlock}() in multi-uprobe attach logic")
Reported-by: Xuewen Yan <xuewen.yan@unisoc.com>
Signed-off-by: Di Shen <di.shen@unisoc.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20250520054943.5002-1-xuewen.yan@unisoc.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | kernel/trace/bpf_trace.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index b0eb721fcfb5..289ff0caa83e 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -3318,7 +3318,9 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr } if (pid) { + rcu_read_lock(); task = get_pid_task(find_vpid(pid), PIDTYPE_TGID); + rcu_read_unlock(); if (!task) { err = -ESRCH; goto error_path_put; |