[PATCH AUTOSEL 5.4 51/51] cifs: prevent NULL deref in cifs_compose_mount_options()
From: Sasha Levin <sashal@kernel.org>
Date: 2021-07-14 19:59:47
Also in:
linux-cifs, lkml
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
From: Paulo Alcantara <redacted>
[ Upstream commit 03313d1c3a2f086bb60920607ab79ac8f8578306 ]
The optional @ref parameter might contain an NULL node_name, so
prevent dereferencing it in cifs_compose_mount_options().
Addresses-Coverity: 1476408 ("Explicit null dereferenced")
Signed-off-by: Paulo Alcantara (SUSE) <redacted>
Signed-off-by: Steve French <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/cifs/cifs_dfs_ref.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c
index cc3ada12848d..42125601ebb1 100644
--- a/fs/cifs/cifs_dfs_ref.c
+++ b/fs/cifs/cifs_dfs_ref.c@@ -151,6 +151,9 @@ char *cifs_compose_mount_options(const char *sb_mountdata, return ERR_PTR(-EINVAL); if (ref) { + if (WARN_ON_ONCE(!ref->node_name || ref->path_consumed < 0)) + return ERR_PTR(-EINVAL); + if (strlen(fullpath) - ref->path_consumed) { prepath = fullpath + ref->path_consumed; /* skip initial delimiter */
--
2.30.2