diff options
| author | Colin Ian King <colin.king@canonical.com> | 2018-11-01 13:14:30 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-11-27 16:10:46 +0100 |
| commit | 426477d9f68b56ab71f52a5ce2dd6da0699d89c3 (patch) | |
| tree | 9cd54a99ed7ac6a01c2fb93cd86348bda623d99d /fs/cifs | |
| parent | 1d4bd2e4e1d26c5384d52ca4a1953cb0cfc934f1 (diff) | |
cifs: don't dereference smb_file_target before null check
[ Upstream commit 8c6c9bed8773375b1d54ccca2911ec892c59db5d ]
There is a null check on dst_file->private data which suggests
it can be potentially null. However, before this check, pointer
smb_file_target is derived from dst_file->private and dereferenced
in the call to tlink_tcon, hence there is a potential null pointer
deference.
Fix this by assigning smb_file_target and target_tcon after the
null pointer sanity checks.
Detected by CoverityScan, CID#1475302 ("Dereference before null check")
Fixes: 04b38d601239 ("vfs: pull btrfs clone API to vfs layer")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs/cifs')
| -rw-r--r-- | fs/cifs/cifsfs.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 44a7b2dea688..c5fd5abf7206 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -933,8 +933,8 @@ static int cifs_clone_file_range(struct file *src_file, loff_t off, struct inode *src_inode = file_inode(src_file); struct inode *target_inode = file_inode(dst_file); struct cifsFileInfo *smb_file_src = src_file->private_data; - struct cifsFileInfo *smb_file_target = dst_file->private_data; - struct cifs_tcon *target_tcon = tlink_tcon(smb_file_target->tlink); + struct cifsFileInfo *smb_file_target; + struct cifs_tcon *target_tcon; unsigned int xid; int rc; @@ -948,6 +948,9 @@ static int cifs_clone_file_range(struct file *src_file, loff_t off, goto out; } + smb_file_target = dst_file->private_data; + target_tcon = tlink_tcon(smb_file_target->tlink); + /* * Note: cifs case is easier than btrfs since server responsible for * checks for proper open modes and file type and if it wants |