From: Paulo Alcantara <pc@cjr.nz>
Date: Mon, 8 Aug 2022 13:41:18 -0300
Subject: [PATCH] cifs: fix lock length calculation
Git-commit: 773891ffd4d628d05c4e22f34541e4779ee7a076
References: bsc#1190317
Patch-mainline: v6.0-rc1
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: d80c69846ddf ("cifs: fix signed integer overflow when fl_end is OFFSET_MAX")
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
fs/cifs/cifsglob.h | 4 ++--
fs/cifs/file.c | 6 +++---
2 files changed, 5 insertions(+), 5 deletions(-)
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -2016,9 +2016,9 @@ static inline bool cifs_is_referral_serv
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;
}
#endif /* _CIFS_GLOB_H */
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1791,9 +1791,9 @@ int cifs_lock(struct file *file, int cmd
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);