| Message ID | 20221111131153.27075-1-jlayton@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | ksmbd: use F_SETLK when unlocking a file | expand |
2022-11-11 22:11 GMT+09:00, Jeff Layton <jlayton@kernel.org>: > ksmbd seems to be trying to use a cmd value of 0 when unlocking a file. > That activity requires a type of F_UNLCK with a cmd of F_SETLK. For > local POSIX locking, it doesn't matter much since vfs_lock_file ignores > @cmd, but filesystems that define their own ->lock operation expect to > see it set sanely. > > Cc: David Howells <dhowells@redhat.com> > Signed-off-by: Jeff Layton <jlayton@kernel.org> Acked-by: Namjae Jeon <linkinjeon@kernel.org> Thanks for your patch.
Jeff Layton <jlayton@kernel.org> wrote: > ksmbd seems to be trying to use a cmd value of 0 when unlocking a file. > That activity requires a type of F_UNLCK with a cmd of F_SETLK. For > local POSIX locking, it doesn't matter much since vfs_lock_file ignores > @cmd, but filesystems that define their own ->lock operation expect to > see it set sanely. > > Cc: David Howells <dhowells@redhat.com> > Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: David Howells <dhowells@redhat.com>
On Fri, Nov 11, 2022 at 08:11:53AM -0500, Jeff Layton wrote: > ksmbd seems to be trying to use a cmd value of 0 when unlocking a file. > That activity requires a type of F_UNLCK with a cmd of F_SETLK. For > local POSIX locking, it doesn't matter much since vfs_lock_file ignores > @cmd, but filesystems that define their own ->lock operation expect to > see it set sanely. Btw, I really wonder if we should split vfs_lock_file into separate calls for locking vs unlocking. The current interface seems very confusing.
On Tue, 2022-11-15 at 01:01 -0800, Christoph Hellwig wrote: > On Fri, Nov 11, 2022 at 08:11:53AM -0500, Jeff Layton wrote: > > ksmbd seems to be trying to use a cmd value of 0 when unlocking a file. > > That activity requires a type of F_UNLCK with a cmd of F_SETLK. For > > local POSIX locking, it doesn't matter much since vfs_lock_file ignores > > @cmd, but filesystems that define their own ->lock operation expect to > > see it set sanely. > > Btw, I really wonder if we should split vfs_lock_file into separate > calls for locking vs unlocking. The current interface seems very > confusing. Maybe, though the current scheme basically of mirrors the userland API, as do the ->lock and ->flock file_operations. FWIW, the filelocking API is pretty rife with warts. Several other things that I wouldn't mind doing, just off the top of my head: - move the file locking API into a separate header. No need for it to be in fs.h, which is already too bloated. - define a new struct for leases, and drop lease-specific fields from file_lock - remove more separate filp and inode arguments - maybe rename locks.c to filelock.c? "locks.c" is too ambiguous Any others?
On Tue, Nov 15, 2022 at 10:22:42AM -0500, Jeff Layton wrote: > Maybe, though the current scheme basically of mirrors the userland API, > as do the ->lock and ->flock file_operations. Yes. But the userland API is pretty horrible and the file_operations should go along with any locks API change. > FWIW, the filelocking API is pretty rife with warts. Several other > things that I wouldn't mind doing, just off the top of my head: > > - move the file locking API into a separate header. No need for it to be > in fs.h, which is already too bloated. > > - define a new struct for leases, and drop lease-specific fields from > file_lock > > - remove more separate filp and inode arguments > > - maybe rename locks.c to filelock.c? "locks.c" is too ambiguous These all sounds pretty reasonable to me.
diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index b2fc85d440d0..f2bcd2a5fb7f 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -6751,7 +6751,7 @@ static int smb2_set_flock_flags(struct file_lock *flock, int flags) case SMB2_LOCKFLAG_UNLOCK: ksmbd_debug(SMB, "received unlock request\n"); flock->fl_type = F_UNLCK; - cmd = 0; + cmd = F_SETLK; break; } @@ -7129,7 +7129,7 @@ int smb2_lock(struct ksmbd_work *work) rlock->fl_start = smb_lock->start; rlock->fl_end = smb_lock->end; - rc = vfs_lock_file(filp, 0, rlock, NULL); + rc = vfs_lock_file(filp, F_SETLK, rlock, NULL); if (rc) pr_err("rollback unlock fail : %d\n", rc);
ksmbd seems to be trying to use a cmd value of 0 when unlocking a file. That activity requires a type of F_UNLCK with a cmd of F_SETLK. For local POSIX locking, it doesn't matter much since vfs_lock_file ignores @cmd, but filesystems that define their own ->lock operation expect to see it set sanely. Cc: David Howells <dhowells@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> --- fs/ksmbd/smb2pdu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)