linux/fs/locks.c, branch v3.4.19

locks: fix checking of fcntl_setlease argument

2012-08-09T15:31:29Z

commit 0ec4f431eb56d633da3a55da67d5c4b88886ccc7 upstream. The only checks of the long argument passed to fcntl(fd,F_SETLEASE,.) are done after converting the long to an int. Thus some illegal values may be let through and cause problems in later code. [ They actually *don't* cause problems in mainline, as of Dave Jones's commit 8d657eb3b438 "Remove easily user-triggerable BUG from generic_setlease", but we should fix this anyway. And this patch will be necessary to fix real bugs on earlier kernels. ] Signed-off-by: J. Bruce Fields Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Remove easily user-triggerable BUG from generic_setlease

2012-07-19T15:58:54Z

commit 8d657eb3b43861064d36241e88d9d61c709f33f0 upstream. This can be trivially triggered from userspace by passing in something unexpected. kernel BUG at fs/locks.c:1468! invalid opcode: 0000 [#1] SMP RIP: 0010:generic_setlease+0xc2/0x100 Call Trace: __vfs_setlease+0x35/0x40 fcntl_setlease+0x76/0x150 sys_fcntl+0x1c6/0x810 system_call_fastpath+0x1a/0x1f Signed-off-by: Dave Jones Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

CIFS: Fix VFS lock usage for oplocked files

2012-04-01T18:54:27Z

We can deadlock if we have a write oplock and two processes use the same file handle. In this case the first process can't unlock its lock if the second process blocked on the lock in the same time. Fix it by using posix_lock_file rather than posix_lock_file_wait under cinode->lock_mutex. If we request a blocking lock and posix_lock_file indicates that there is another lock that prevents us, wait untill that lock is released and restart our call. Cc: stable@kernel.org Acked-by: Jeff Layton Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French

vfs: fix handling of lock allocation failure in lease-break case

2011-12-26T18:25:26Z

Bruce Fields notes that commit 778fc546f749 ("locks: fix tracking of inprogress lease breaks") introduced a possible error pointer dereference on failure to allocate memory. locks_conflict() will dereference the passed-in new lease lock structure that may be an error pointer. This means an open (without O_NONBLOCK set) on a file with a lease applied (generally only done when Samba or nfsd (with v4) is running) could crash if a kmalloc() fails. So instead of playing games with IS_ERROR() all over the place, just check the allocation failure early. That makes the code more straightforward, and avoids this possible bad pointer dereference. Based-on-patch-by: J. Bruce Fields Cc: Al Viro Signed-off-by: Linus Torvalds

Merge branch 'for-3.2' of git://linux-nfs.org/~bfields/linux

2011-10-25T13:42:01Z

* 'for-3.2' of git://linux-nfs.org/~bfields/linux: (103 commits) nfs41: implement DESTROY_CLIENTID operation nfsd4: typo logical vs bitwise negate for want_mask nfsd4: allow NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL | NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED nfsd4: seq->status_flags may be used unitialized nfsd41: use SEQ4_STATUS_BACKCHANNEL_FAULT when cb_sequence is invalid nfsd4: implement new 4.1 open reclaim types nfsd4: remove unneeded CLAIM_DELEGATE_CUR workaround nfsd4: warn on open failure after create nfsd4: preallocate open stateid in process_open1() nfsd4: do idr preallocation with stateid allocation nfsd4: preallocate nfs4_file in process_open1() nfsd4: clean up open owners on OPEN failure nfsd4: simplify process_open1 logic nfsd4: make is_open_owner boolean nfsd4: centralize renew_client() calls nfsd4: typo logical vs bitwise negate nfs: fix bug about IPv6 address scope checking nfsd4: more robust ignoring of WANT bits in OPEN nfsd4: move name-length checks to xdr nfsd4: move access/deny validity checks to xdr code ...

doc: fix broken references

2011-09-27T16:08:04Z

There are numerous broken references to Documentation files (in other Documentation files, in comments, etc.). These broken references are caused by typo's in the references, and by renames or removals of the Documentation files. Some broken references are simply odd. Fix these broken references, sometimes by dropping the irrelevant text they were part of. Signed-off-by: Paul Bolle Signed-off-by: Jiri Kosina

leases: split up generic_setlease into lock/unlock cases

2011-09-21T14:40:54Z

Eventually we should probably do the same thing to the file operations as well. Signed-off-by: J. Bruce Fields

locks: setlease cleanup

2011-08-19T17:25:35Z

There's an incorrect comment here. Also clean up the logic: the "rdlease" and "wrlease" locals are confusingly named, and don't really add anything since we can make a decision as soon as we hit one of these cases. Signed-off-by: J. Bruce Fields

locks: fix tracking of inprogress lease breaks

2011-08-19T17:25:34Z

We currently use a bit in fl_flags to record whether a lease is being broken, and set fl_type to the type (RDLCK or UNLCK) that it will eventually have. This means that once the lease break starts, we forget what the lease's type *used* to be. Breaking a read lease will then result in blocking read opens, even though there's no conflict--because the lease type is now F_UNLCK and we can no longer tell whether it was previously a read or write lease. So, instead keep fl_type as the original type (the type which we enforce), and keep track of whether we're unlocking or merely downgrading by replacing the single FL_INPROGRESS flag by FL_UNLOCK_PENDING and FL_DOWNGRADE_PENDING flags. To get this right we also need to track separate downgrade and break times, to handle the case where a write-leased file gets conflicting opens first for read, then later for write. (I first considered just eliminating the downgrade behavior completely--nfsv4 doesn't need it, and nobody as far as I can tell actually uses it currently--but Jeremy Allison tells me that Windows oplocks do behave this way, so Samba will probably use this some day.) Reviewed-by: Jeff Layton Signed-off-by: J. Bruce Fields

locks: move F_INPROGRESS from fl_type to fl_flags field

2011-08-19T17:25:34Z

F_INPROGRESS isn't exposed to userspace. To me it makes more sense in fl_flags.... Reviewed-by: Jeff Layton Signed-off-by: J. Bruce Fields