diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-09-28 13:02:53 -0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-09-28 13:02:53 -0400 |
commit | 7596824e6626c62557b9eb6411ee74fec68b8ff9 (patch) | |
tree | 4a906422538887be858b9cbdf848d68f8db6c116 /fs | |
parent | 97956605d8f2a0d17706cbd338a6cfe8de1920e9 (diff) | |
parent | c5aa1e554a20fb3542c62688ae46049c9225a965 (diff) |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
"A couple of fixes; one for automount/lazy umount race, another a
classic "we don't protect the refcount transition to zero with the
lock that protects looking for object in hash" kind of crap in lockd."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
close the race in nlmsvc_free_block()
do_add_mount()/umount -l races
Diffstat (limited to 'fs')
-rw-r--r-- | fs/lockd/svclock.c | 3 | ||||
-rw-r--r-- | fs/namespace.c | 10 |
2 files changed, 9 insertions, 4 deletions
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c index fb1a2bedbe9..8d80c990dff 100644 --- a/fs/lockd/svclock.c +++ b/fs/lockd/svclock.c | |||
@@ -289,7 +289,6 @@ static void nlmsvc_free_block(struct kref *kref) | |||
289 | dprintk("lockd: freeing block %p...\n", block); | 289 | dprintk("lockd: freeing block %p...\n", block); |
290 | 290 | ||
291 | /* Remove block from file's list of blocks */ | 291 | /* Remove block from file's list of blocks */ |
292 | mutex_lock(&file->f_mutex); | ||
293 | list_del_init(&block->b_flist); | 292 | list_del_init(&block->b_flist); |
294 | mutex_unlock(&file->f_mutex); | 293 | mutex_unlock(&file->f_mutex); |
295 | 294 | ||
@@ -303,7 +302,7 @@ static void nlmsvc_free_block(struct kref *kref) | |||
303 | static void nlmsvc_release_block(struct nlm_block *block) | 302 | static void nlmsvc_release_block(struct nlm_block *block) |
304 | { | 303 | { |
305 | if (block != NULL) | 304 | if (block != NULL) |
306 | kref_put(&block->b_count, nlmsvc_free_block); | 305 | kref_put_mutex(&block->b_count, nlmsvc_free_block, &block->b_file->f_mutex); |
307 | } | 306 | } |
308 | 307 | ||
309 | /* | 308 | /* |
diff --git a/fs/namespace.c b/fs/namespace.c index 4d31f73e256..7bdf7907413 100644 --- a/fs/namespace.c +++ b/fs/namespace.c | |||
@@ -1886,8 +1886,14 @@ static int do_add_mount(struct mount *newmnt, struct path *path, int mnt_flags) | |||
1886 | return err; | 1886 | return err; |
1887 | 1887 | ||
1888 | err = -EINVAL; | 1888 | err = -EINVAL; |
1889 | if (!(mnt_flags & MNT_SHRINKABLE) && !check_mnt(real_mount(path->mnt))) | 1889 | if (unlikely(!check_mnt(real_mount(path->mnt)))) { |
1890 | goto unlock; | 1890 | /* that's acceptable only for automounts done in private ns */ |
1891 | if (!(mnt_flags & MNT_SHRINKABLE)) | ||
1892 | goto unlock; | ||
1893 | /* ... and for those we'd better have mountpoint still alive */ | ||
1894 | if (!real_mount(path->mnt)->mnt_ns) | ||
1895 | goto unlock; | ||
1896 | } | ||
1891 | 1897 | ||
1892 | /* Refuse the same filesystem on the same mount point */ | 1898 | /* Refuse the same filesystem on the same mount point */ |
1893 | err = -EBUSY; | 1899 | err = -EBUSY; |