[PATCH next] audit: fix potential double free on error path from fsnotify_add_inode_mark

From: Gaosheng Cui
Date: Sun Aug 21 2022 - 22:29:15 EST


Audit_alloc_mark() assign pathname to audit_mark->path, on error path
from fsnotify_add_inode_mark(), fsnotify_put_mark will free memory
of audit_mark->path, but the caller of audit_alloc_mark will free
the pathname again, so there will be double free problem.

Fix this by resetting audit_mark->path to NULL pointer on error path
from fsnotify_add_inode_mark().

Fixes: 7b1293234084d ("fsnotify: Add group pointer in fsnotify_init_mark()")
Signed-off-by: Gaosheng Cui <cuigaosheng1@xxxxxxxxxx>
---
kernel/audit_fsnotify.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/kernel/audit_fsnotify.c b/kernel/audit_fsnotify.c
index 6432a37ac1c9..c565fbf66ac8 100644
--- a/kernel/audit_fsnotify.c
+++ b/kernel/audit_fsnotify.c
@@ -102,6 +102,7 @@ struct audit_fsnotify_mark *audit_alloc_mark(struct audit_krule *krule, char *pa

ret = fsnotify_add_inode_mark(&audit_mark->mark, inode, 0);
if (ret < 0) {
+ audit_mark->path = NULL;
fsnotify_put_mark(&audit_mark->mark);
audit_mark = ERR_PTR(ret);
}
--
2.25.1