diff options
| author | Shyam Prasad N <sprasad@microsoft.com> | 2023-06-22 18:16:03 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-07-11 19:39:51 +0200 |
| commit | b6353518ef8180816e863aa23b06456f395404d6 (patch) | |
| tree | 87a172271090ff7b0ef250d2b4a6f2a4727087c5 | |
| parent | 1df929db46b8f15dce5adafc2e62f88395fd8755 (diff) | |
cifs: prevent use-after-free by freeing the cfile later
[ Upstream commit 33f736187d08f6bc822117629f263b97d3df4165 ]
In smb2_compound_op we have a possible use-after-free
which can cause hard to debug problems later on.
This was revealed during stress testing with KASAN enabled
kernel. Fixing it by moving the cfile free call to
a few lines below, after the usage.
Fixes: 76894f3e2f71 ("cifs: improve symlink handling for smb2+")
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | fs/cifs/smb2inode.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c index 163a03298430..7e3ac4cb4efa 100644 --- a/fs/cifs/smb2inode.c +++ b/fs/cifs/smb2inode.c @@ -398,9 +398,6 @@ static int smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, rsp_iov); finished: - if (cfile) - cifsFileInfo_put(cfile); - SMB2_open_free(&rqst[0]); if (rc == -EREMCHG) { pr_warn_once("server share %s deleted\n", tcon->tree_name); @@ -529,6 +526,9 @@ static int smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, break; } + if (cfile) + cifsFileInfo_put(cfile); + if (rc && err_iov && err_buftype) { memcpy(err_iov, rsp_iov, 3 * sizeof(*err_iov)); memcpy(err_buftype, resp_buftype, 3 * sizeof(*err_buftype)); |