eventfs: Test for dentries array allocated in eventfs_release()

The dcache_dir_open_wrapper() could be called when a dynamic event is
being deleted leaving a dentry with no children. In this case the
dlist->dentries array will never be allocated. This needs to be checked
for in eventfs_release(), otherwise it will trigger a NULL pointer
dereference.

Link: https://lore.kernel.org/linux-trace-kernel/20230930090106.1c3164e9@rorschach.local.home

Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Fixes: ef36b4f928 ("eventfs: Remember what dentries were created on dir open")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Google) 2023-09-30 09:01:06 -04:00
parent 2de9ee9405
commit 2598bd3ca8

View file

@ -421,7 +421,7 @@ static int eventfs_release(struct inode *inode, struct file *file)
if (WARN_ON_ONCE(!dlist))
return -EINVAL;
for (i = 0; dlist->dentries[i]; i++) {
for (i = 0; dlist->dentries && dlist->dentries[i]; i++) {
dput(dlist->dentries[i]);
}