summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorRoss Lagerwall <ross.lagerwall@citrix.com>2019-01-08 18:30:57 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-01-16 22:16:10 +0100
commit9c87abaf4d12413531ce689b781120ebaeeef044 (patch)
tree1cffc5e67c1a89e383bcaca21acf3a80d231641e
parent05ce0d9d5600b88f72427fc93613ef09006b3f91 (diff)
cifs: Fix potential OOB access of lock element array
commit b9a74cde94957d82003fb9f7ab4777938ca851cd upstream. If maxBuf is small but non-zero, it could result in a zero sized lock element array which we would then try and access OOB. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--fs/cifs/file.c8
-rw-r--r--fs/cifs/smb2file.c4
2 files changed, 6 insertions, 6 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 0141aba9eca6..026b399af215 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1073,10 +1073,10 @@ cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
/*
* Accessing maxBuf is racy with cifs_reconnect - need to store value
- * and check it for zero before using.
+ * and check it before using.
*/
max_buf = tcon->ses->server->maxBuf;
- if (!max_buf) {
+ if (max_buf < (sizeof(struct smb_hdr) + sizeof(LOCKING_ANDX_RANGE))) {
free_xid(xid);
return -EINVAL;
}
@@ -1404,10 +1404,10 @@ cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
/*
* Accessing maxBuf is racy with cifs_reconnect - need to store value
- * and check it for zero before using.
+ * and check it before using.
*/
max_buf = tcon->ses->server->maxBuf;
- if (!max_buf)
+ if (max_buf < (sizeof(struct smb_hdr) + sizeof(LOCKING_ANDX_RANGE)))
return -EINVAL;
max_num = (max_buf - sizeof(struct smb_hdr)) /
diff --git a/fs/cifs/smb2file.c b/fs/cifs/smb2file.c
index b2aff0c6f22c..b7885dc0d9bb 100644
--- a/fs/cifs/smb2file.c
+++ b/fs/cifs/smb2file.c
@@ -123,10 +123,10 @@ smb2_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
/*
* Accessing maxBuf is racy with cifs_reconnect - need to store value
- * and check it for zero before using.
+ * and check it before using.
*/
max_buf = tcon->ses->server->maxBuf;
- if (!max_buf)
+ if (max_buf < sizeof(struct smb2_lock_element))
return -EINVAL;
max_num = max_buf / sizeof(struct smb2_lock_element);