lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[CIFS] Byte range unlock request to non-Unix server can unlock too much

Browse Source 
On a mount without posix extensions enabled, when an unlock request is
made, the client can release more than is intended. To reproduce, on a
CIFS mount without posix extensions enabled:

1) open file
2) do fcntl lock: start=0 len=1
3) do fcntl lock: start=2 len=1
4) do fcntl unlock: start=0 len=1

...on the unlock call the client sends an unlock request to the server
for both locks. The problem is a bad test in cifs_lock.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This commit is contained in:
Jeff Layton
2007-08-24 03:16:51 +00:00
committed by Steve French
parent 95ba736210
commit 39db810cb6
2 changed files with 6 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
fs/cifs/file.c
View File

@ -767,7 +767,8 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
mutex_lock(&fid->lock_mutex);
list_for_each_entry_safe(li, tmp, &fid->llist, llist) {
if (pfLock->fl_start <= li->offset &&
length >= li->length) {
(pflock->fl_start + length) >=
(li->offset + li->length)) {
stored_rc = CIFSSMBLock(xid, pTcon,
netfid,
li->length, li->offset,