diff options
| author |   Jeff Layton <jlayton@redhat.com> | 2014-03-10 09:54:15 -0400 |
|---|---|---|
| committer | Jeff Layton <jlayton@redhat.com> | 2014-03-31 08:24:43 -0400 |
| commit | d7a06983a01a33605191c0766857b832ac32a2b6 (patch) | |
| tree | d6a0f83579e0d7a20a235ddb568d935fe54b24fb /mm | |
| parent | locks: require that flock->l_pid be set to 0 for file-private locks (diff) | |
| download | linux-dev-d7a06983a01a33605191c0766857b832ac32a2b6.tar.xz linux-dev-d7a06983a01a33605191c0766857b832ac32a2b6.zip | |
locks: fix locks_mandatory_locked to respect file-private locks
As Trond pointed out, you can currently deadlock yourself by setting a
file-private lock on a file that requires mandatory locking and then
trying to do I/O on it.
Avoid this problem by plumbing some knowledge of file-private locks into
the mandatory locking code. In order to do this, we must pass down
information about the struct file that's being used to
locks_verify_locked.
Reported-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/mmap.c | 2 | ||||
| -rw-r--r-- | mm/nommu.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 20ff0c33274c..5932ce961218 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1299,7 +1299,7 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, /* * Make sure there are no mandatory locks on the file. */ - if (locks_verify_locked(inode)) + if (locks_verify_locked(file)) return -EAGAIN; vm_flags |= VM_SHARED | VM_MAYSHARE; diff --git a/mm/nommu.c b/mm/nommu.c index 8740213b1647..a554e5a451cd 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -995,7 +995,7 @@ static int validate_mmap_request(struct file *file, (file->f_mode & FMODE_WRITE)) return -EACCES; - if (locks_verify_locked(file_inode(file))) + if (locks_verify_locked(file)) return -EAGAIN; if (!(capabilities & BDI_CAP_MAP_DIRECT)) |