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| author | Marc Dionne <marc.dionne@auristor.com> | 2017-07-06 16:50:18 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-07-09 23:40:12 +0200 |
| commit | fd2498211a551fd42b2d6b9050d649d43536e75c (patch) | |
| tree | 584019e61d101ed7bdfa209c55463da751ed55ae /fs/afs/security.c | |
| parent | mqueue: fix a use-after-free in sys_mq_notify() (diff) | |
| download | linux-fd2498211a551fd42b2d6b9050d649d43536e75c.tar.xz linux-fd2498211a551fd42b2d6b9050d649d43536e75c.zip | |
afs: Ignore AFS_ACE_READ and AFS_ACE_WRITE for directories
The AFS_ACE_READ and AFS_ACE_WRITE permission bits should not
be used to make access decisions for the directory itself. They
are meant to control access for the objects contained in that
directory.
Reading a directory is allowed if the AFS_ACE_LOOKUP bit is set.
This would cause an incorrect access denied error for a directory
with AFS_ACE_LOOKUP but not AFS_ACE_READ.
The AFS_ACE_WRITE bit does not allow operations that modify the
directory. For a directory with AFS_ACE_WRITE but neither
AFS_ACE_INSERT nor AFS_ACE_DELETE, this would result in trying
operations that would ultimately be denied by the server.
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/afs/security.c')
| -rw-r--r-- | fs/afs/security.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/fs/afs/security.c b/fs/afs/security.c index ecb86a670180..faca66227ecf 100644 --- a/fs/afs/security.c +++ b/fs/afs/security.c @@ -327,12 +327,11 @@ int afs_permission(struct inode *inode, int mask) if (!(access & AFS_ACE_LOOKUP)) goto permission_denied; } else if (mask & MAY_READ) { - if (!(access & AFS_ACE_READ)) + if (!(access & AFS_ACE_LOOKUP)) goto permission_denied; } else if (mask & MAY_WRITE) { if (!(access & (AFS_ACE_DELETE | /* rmdir, unlink, rename from */ - AFS_ACE_INSERT | /* create, mkdir, symlink, rename to */ - AFS_ACE_WRITE))) /* chmod */ + AFS_ACE_INSERT))) /* create, mkdir, symlink, rename to */ goto permission_denied; } else { BUG(); |