summaryrefslogtreecommitdiffstats
path: root/fs
diff options
context:
space:
mode:
authorDavid Howells <dhowells@redhat.com>2022-06-21 15:59:57 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2022-06-21 11:47:30 -0500
commitcb78d1b5efffe4cf97e16766329dd7358aed3deb (patch)
tree21ef8ae07a03eea8f99e07ea6bc322877f8202c5 /fs
parent78ca55889a549a9a194c6ec666836329b774ab6d (diff)
downloadlinux-cb78d1b5efffe4cf97e16766329dd7358aed3deb.tar.bz2
afs: Fix dynamic root getattr
The recent patch to make afs_getattr consult the server didn't account for the pseudo-inodes employed by the dynamic root-type afs superblock not having a volume or a server to access, and thus an oops occurs if such a directory is stat'd. Fix this by checking to see if the vnode->volume pointer actually points anywhere before following it in afs_getattr(). This can be tested by stat'ing a directory in /afs. It may be sufficient just to do "ls /afs" and the oops looks something like: BUG: kernel NULL pointer dereference, address: 0000000000000020 ... RIP: 0010:afs_getattr+0x8b/0x14b ... Call Trace: <TASK> vfs_statx+0x79/0xf5 vfs_fstatat+0x49/0x62 Fixes: 2aeb8c86d499 ("afs: Fix afs_getattr() to refetch file status if callback break occurred") Reported-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Tested-by: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/165408450783.1031787.7941404776393751186.stgit@warthog.procyon.org.uk/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
-rw-r--r--fs/afs/inode.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index 89630acbc2cc..64dab70d4a4f 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -745,7 +745,8 @@ int afs_getattr(struct user_namespace *mnt_userns, const struct path *path,
_enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
- if (!(query_flags & AT_STATX_DONT_SYNC) &&
+ if (vnode->volume &&
+ !(query_flags & AT_STATX_DONT_SYNC) &&
!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
key = afs_request_key(vnode->volume->cell);
if (IS_ERR(key))