diff options
| author | Tim Chase <[email protected]> | 2013-06-24 22:03:56 -0500 |
|---|---|---|
| committer | Brian Behlendorf <[email protected]> | 2013-07-01 14:51:45 -0700 |
| commit | ab68b6e5db29abcd20c0c7b12a8c2fa570031c8b (patch) | |
| tree | b63560481a046181a28132572591f4e406d89701 | |
| parent | 64d7b6cf75e52a4698d9bdec61745573c39d2e5a (diff) | |
Fix zfs_sb_teardown/zfs_resume_fs NULL dereference
Fix a pair of conditions in which a concurrent umount can cause
NULL pointer dereferences:
* zfs_sb_teardown - prevent a NULL dereference by not calling
dmu_objset_pool with a null z_os.
* zfs_resume_fs - don't try to unmount with a null z_os. This
change makes the ZoL code more consistent
with both Illumos and FreeBSD.
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #1543
| -rw-r--r-- | module/zfs/zfs_vfsops.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/module/zfs/zfs_vfsops.c b/module/zfs/zfs_vfsops.c index e618f2bbf..602c332ea 100644 --- a/module/zfs/zfs_vfsops.c +++ b/module/zfs/zfs_vfsops.c @@ -1056,10 +1056,12 @@ zfs_sb_teardown(zfs_sb_t *zsb, boolean_t unmounting) } /* - * Drain the iput_taskq to ensure all active references to the + * If someone has not already unmounted this file system, + * drain the iput_taskq to ensure all active references to the * zfs_sb_t have been handled only then can it be safely destroyed. */ - taskq_wait(dsl_pool_iput_taskq(dmu_objset_pool(zsb->z_os))); + if (zsb->z_os) + taskq_wait(dsl_pool_iput_taskq(dmu_objset_pool(zsb->z_os))); /* * Close the zil. NB: Can't close the zil while zfs_inactive @@ -1480,10 +1482,11 @@ bail: if (err) { /* - * Since we couldn't reopen zfs_sb_t, force - * unmount this file system. + * Since we couldn't reopen zfs_sb_t or, setup the + * sa framework, force unmount this file system. */ - (void) zfs_umount(zsb->z_sb); + if (zsb->z_os) + (void) zfs_umount(zsb->z_sb); } return (err); } |