linux/fs/afs
David Howells 17eabd4256 afs: Fix infinite loop found by xfstest generic/676
In AFS, a directory is handled as a file that the client downloads and
parses locally for the purposes of performing lookup and getdents
operations.  The in-kernel afs filesystem has a number of functions that
do this.

A directory file is arranged as a series of 2K blocks divided into
32-byte slots, where a directory entry occupies one or more slots, plus
each block starts with one or more metadata blocks.

When parsing a block, if the last slots are occupied by a dirent that
occupies more than a single slot and the file position points at a slot
that's not the initial one, the logic in afs_dir_iterate_block() that
skips over it won't advance the file pointer to the end of it.  This
will cause an infinite loop in getdents() as it will keep retrying that
block and failing to advance beyond the final entry.

Fix this by advancing the file pointer if the next entry will be beyond
it when we skip a block.

This was found by the generic/676 xfstest but can also be triggered with
something like:

	~/xfstests-dev/src/t_readdir_3 /xfstest.test/z 4000 1

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
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: http://lore.kernel.org/r/165391973497.110268.2939296942213894166.stgit@warthog.procyon.org.uk/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-06-01 11:11:51 -07:00
..
addr_list.c afs: Use kfree_rcu() instead of casting kfree() to rcu_callback_t 2020-03-13 10:47:33 -07:00
afs_cm.h
afs_fs.h
afs_vl.h afs: Implement client support for the YFSVL.GetCellName RPC op 2020-06-04 15:37:57 +01:00
afs.h afs: Implement client support for the YFSVL.GetCellName RPC op 2020-06-04 15:37:57 +01:00
callback.c afs: Try to avoid taking RCU read lock when checking vnode validity 2021-09-13 09:10:39 +01:00
cell.c afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
cmservice.c afs: Fix tracepoint string placement with built-in AFS 2021-07-21 15:08:35 +01:00
dir_edit.c afs: Use folios in directory handling 2021-11-10 21:17:09 +00:00
dir_silly.c afs: Fix kerneldoc warning shown up by W=1 2021-10-04 22:04:44 +01:00
dir.c afs: Fix infinite loop found by xfstest generic/676 2022-06-01 11:11:51 -07:00
dynroot.c netfs: Add a netfs inode context 2022-03-18 09:29:05 +00:00
file.c afs: Convert to release_folio 2022-05-09 23:12:32 -04:00
flock.c fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
fs_operation.c afs: Fix speculative status fetches 2021-05-01 11:55:36 -07:00
fs_probe.c afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS server 2021-09-13 09:14:21 +01:00
fsclient.c afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS server 2021-09-13 09:14:21 +01:00
inode.c afs: Fix afs_getattr() to refetch file status if callback break occurred 2022-05-22 09:25:47 -10:00
internal.h afs: Convert to release_folio 2022-05-09 23:12:32 -04:00
Kconfig afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
main.c afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
Makefile afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
misc.c afs: Adjust ACK interpretation to try and cope with NAT 2022-05-22 21:03:02 +01:00
mntpt.c afs: Stop listxattr() from listing "afs.*" attributes 2021-03-15 17:09:54 +00:00
proc.c proc: remove PDE_DATA() completely 2022-01-22 08:33:37 +02:00
protocol_afs.h afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS server 2021-09-13 09:14:21 +01:00
protocol_uae.h
protocol_yfs.h afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS server 2021-09-13 09:14:21 +01:00
rotate.c afs: Adjust ACK interpretation to try and cope with NAT 2022-05-22 21:03:02 +01:00
rxrpc.c rxrpc, afs: Fix selection of abort codes 2022-05-22 21:03:02 +01:00
security.c afs: Prefer struct_size over open coded arithmetic 2022-04-26 10:20:00 -05:00
server_list.c afs: Reorganise volume and server trees to be rooted on the cell 2020-06-04 15:37:57 +01:00
server.c afs: Fix mmap coherency vs 3rd-party changes 2021-09-13 09:10:39 +01:00
super.c Netfs prep for write helpers 2022-03-31 15:49:36 -07:00
vl_alias.c afs: Add tracing for cell refcount and active user count 2020-10-16 14:39:21 +01:00
vl_list.c afs: Don't use VL probe running state to make decisions outside probe code 2020-08-20 18:21:28 +01:00
vl_probe.c afs: Don't use VL probe running state to make decisions outside probe code 2020-08-20 18:21:28 +01:00
vl_rotate.c afs: Add tracing for cell refcount and active user count 2020-10-16 14:39:21 +01:00
vlclient.c afs: Fix fall-through warnings for Clang 2021-05-25 07:30:34 -10:00
volume.c afs: Convert afs to use the new fscache API 2022-01-07 13:44:47 +00:00
write.c Networking changes for 5.19. 2022-05-25 12:22:58 -07:00
xattr.c afs: Stop listxattr() from listing "afs.*" attributes 2021-03-15 17:09:54 +00:00
xdr_fs.h afs: Fix directory entry size calculation 2021-01-04 12:25:19 +00:00
yfsclient.c afs: Set mtime from the client for yfs create operations 2021-11-02 09:42:26 +00:00