On Tue, 2011-05-31 at 14:20 +1000, Dave Chinner wrote: > From: Dave Chinner <dchinner@xxxxxxxxxx> > > If the attribute fork on an inode is in btree format and has > multiple levels (i.e node format rather than leaf format), then a > lookup failure will trigger an assert failure in xfs_da_path_shift > if the flag XFS_DA_OP_OKNOENT is not set. This flag is used to > indicate to the directory btree code that not finding an entry is > not a fatal error. In the case of doing a lookup for a directory > name removal, this is valid as a user cannot insert an arbitrary > name to remove from the directory btree. > > However, in the case of the attribute tree, a user has direct > control over the attribute name and can ask for any random name to > be removed without any validation. In this case, fsstress is asking > for a non-existent user.selinux attribute to be removed, and that is > causing xfs_da_path_shift() to fall off the bottom of the tree where > it asserts that a lookup failure is allowed. Because the flag is not > set, we die a horrible death on a debug enable kernel. > > Prevent this assert from firing on attribute removes by adding the > op_flag XFS_DA_OP_OKNOENT to atribute removal operations. > > Discovered when testing on a SELinux enabled system by fsstress in > test 070 by trying to remove a non-existent user.selinux attribute. > > Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> I have not carefully verified this change, but your description of the problem was very good so based on this the change looks right to me. Signed-off-by: Alex Elder <aelder@xxxxxxx> _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
