cifs: fix lock length calculation

The lock length was wrongly set to 0 when fl_end == OFFSET_MAX, thus failing to lock the whole file when l_start=0 and l_len=0. This fixes test 2 from cthon04. Before patch: $ ./cthon04/lock/tlocklfs -t 2 /mnt Creating parent/child synchronization pipes. Test #1 - Test regions of an unlocked file. Parent: 1.1 - F_TEST [ 0, 1] PASSED. Parent: 1.2 - F_TEST [ 0, ENDING] PASSED. Parent: 1.3 - F_TEST [ 0,7fffffffffffffff] PASSED. Parent: 1.4 - F_TEST [ 1, 1] PASSED. Parent: 1.5 - F_TEST [ 1, ENDING] PASSED. Parent: 1.6 - F_TEST [ 1,7fffffffffffffff] PASSED. Parent: 1.7 - F_TEST [7fffffffffffffff, 1] PASSED. Parent: 1.8 - F_TEST [7fffffffffffffff, ENDING] PASSED. Parent: 1.9 - F_TEST [7fffffffffffffff,7fffffffffffffff] PASSED. Test #2 - Try to lock the whole file. Parent: 2.0 - F_TLOCK [ 0, ENDING] PASSED. Child: 2.1 - F_TEST [ 0, 1] FAILED! Child: **** Expected EACCES, returned success... Child: **** Probably implementation error. ** CHILD pass 1 results: 0/0 pass, 0/0 warn, 1/1 fail (pass/total). Parent: Child died ** PARENT pass 1 results: 10/10 pass, 0/0 warn, 0/0 fail (pass/total). After patch: $ ./cthon04/lock/tlocklfs -t 2 /mnt Creating parent/child synchronization pipes. Test #2 - Try to lock the whole file. Parent: 2.0 - F_TLOCK [ 0, ENDING] PASSED. Child: 2.1 - F_TEST [ 0, 1] PASSED. Child: 2.2 - F_TEST [ 0, ENDING] PASSED. Child: 2.3 - F_TEST [ 0,7fffffffffffffff] PASSED. Child: 2.4 - F_TEST [ 1, 1] PASSED. Child: 2.5 - F_TEST [ 1, ENDING] PASSED. Child: 2.6 - F_TEST [ 1,7fffffffffffffff] PASSED. Child: 2.7 - F_TEST [7fffffffffffffff, 1] PASSED. Child: 2.8 - F_TEST [7fffffffffffffff, ENDING] PASSED. Child: 2.9 - F_TEST [7fffffffffffffff,7fffffffffffffff] PASSED. Parent: 2.10 - F_ULOCK [ 0, ENDING] PASSED. ** PARENT pass 1 results: 2/2 pass, 0/0 warn, 0/0 fail (pass/total). ** CHILD pass 1 results: 9/9 pass, 0/0 warn, 0/0 fail (pass/total). Fixes: d80c698 ("cifs: fix signed integer overflow when fl_end is OFFSET_MAX") Reported-by: Xiaoli Feng <[email protected]> Cc: <[email protected]> Signed-off-by: Paulo Alcantara (SUSE) <[email protected]> Reviewed-by: Ronnie Sahlberg <[email protected]> Signed-off-by: Steve French <[email protected]>
aospm · Aug 10, 2022 · 773891f · 773891f
1 parent 0d168a5
commit 773891f
Show file tree

Hide file tree

Showing 2 changed files with 5 additions and 5 deletions.
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
@@ -2132,9 +2132,9 @@ static inline bool cifs_is_referral_server(struct cifs_tcon *tcon,
 	return is_tcon_dfs(tcon) || (ref && (ref->flags & DFSREF_REFERRAL_SERVER));
 }
 
-static inline u64 cifs_flock_len(struct file_lock *fl)
+static inline u64 cifs_flock_len(const struct file_lock *fl)
 {
-	return fl->fl_end == OFFSET_MAX ? 0 : fl->fl_end - fl->fl_start + 1;
+	return (u64)fl->fl_end - fl->fl_start + 1;
 }
 
 static inline size_t ntlmssp_workstation_name_size(const struct cifs_ses *ses)

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
@@ -1936,9 +1936,9 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *flock)
 	rc = -EACCES;
 	xid = get_xid();
 
-	cifs_dbg(FYI, "Lock parm: 0x%x flockflags: 0x%x flocktype: 0x%x start: %lld end: %lld\n",
-		 cmd, flock->fl_flags, flock->fl_type,
-		 flock->fl_start, flock->fl_end);
+	cifs_dbg(FYI, "%s: %pD2 cmd=0x%x type=0x%x flags=0x%x r=%lld:%lld\n", __func__, file, cmd,
+		 flock->fl_flags, flock->fl_type, (long long)flock->fl_start,
+		 (long long)flock->fl_end);
 
 	cfile = (struct cifsFileInfo *)file->private_data;
 	tcon = tlink_tcon(cfile->tlink);