linux/fs/afs
David Howells 366911cd76 afs: Fix directory entry size calculation
The number of dirent records used by an AFS directory entry should be
calculated using the assumption that there is a 16-byte name field in the
first block, rather than a 20-byte name field (which is actually the case).
This miscalculation is historic and effectively standard, so we have to use
it.

The calculation we need to use is:

	1 + (((strlen(name) + 1) + 15) >> 5)

where we are adding one to the strlen() result to account for the NUL
termination.

Fix this by the following means:

 (1) Create an inline function to do the calculation for a given name
     length.

 (2) Use the function to calculate the number of records used for a dirent
     in afs_dir_iterate_block().

     Use this to move the over-end check out of the loop since it only
     needs to be done once.

     Further use this to only go through the loop for the 2nd+ records
     composing an entry.  The only test there now is for if the record is
     allocated - and we already checked the first block at the top of the
     outer loop.

 (3) Add a max name length check in afs_dir_iterate_block().

 (4) Make afs_edit_dir_add() and afs_edit_dir_remove() use the function
     from (1) to calculate the number of blocks rather than doing it
     incorrectly themselves.

Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
2021-01-04 12:25:19 +00:00
..
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 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
afs_fs.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
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
cache.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
callback.c afs: Fix the by-UUID server tree to allow servers with the same UUID 2020-06-04 15:37:57 +01:00
cell.c afs: Fix tracing deref-before-check 2020-10-27 22:05:56 +00:00
cmservice.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
dir_edit.c afs: Fix directory entry size calculation 2021-01-04 12:25:19 +00:00
dir_silly.c afs: Fix silly rename 2020-06-16 22:00:28 +01:00
dir.c afs: Fix directory entry size calculation 2021-01-04 12:25:19 +00:00
dynroot.c afs: Add tracing for cell refcount and active user count 2020-10-16 14:39:21 +01:00
file.c afs: Fix afs_invalidatepage to adjust the dirty region 2020-10-29 13:53:04 +00:00
flock.c afs: Remove erroneous fallthough annotation 2020-08-27 14:33:01 -05:00
fs_operation.c afs: Fix key ref leak in afs_put_operation() 2020-08-20 10:41:45 -07:00
fs_probe.c rxrpc: Make rxrpc_kernel_get_srtt() indicate validity 2020-08-20 18:21:28 +01:00
fsclient.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
inode.c afs: Fix speculative status fetch going out of order wrt to modifications 2020-11-22 11:27:03 -08:00
internal.h afs: Fix speculative status fetch going out of order wrt to modifications 2020-11-22 11:27:03 -08:00
Kconfig docs: filesystems: fix renamed references 2020-04-20 15:45:22 -06:00
main.c afs: Fix rapid cell addition/removal by not using RCU on cells tree 2020-10-16 14:04:59 +01:00
Makefile afs: Detect cell aliases 1 - Cells with root volumes 2020-06-04 15:37:57 +01:00
misc.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
mntpt.c afs: Add tracing for cell refcount and active user count 2020-10-16 14:39:21 +01:00
proc.c afs: Add tracing for cell refcount and active user count 2020-10-16 14:39:21 +01:00
protocol_uae.h afs: Add support for the UAE error table 2019-06-28 18:37:53 +01:00
protocol_yfs.h afs: Implement client support for the YFSVL.GetCellName RPC op 2020-06-04 15:37:57 +01:00
rotate.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
rxrpc.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
security.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
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: Don't assert on unpurgeable server records 2020-10-16 14:39:34 +01:00
super.c afs: Fix memory leak when mounting with multiple source parameters 2020-12-08 15:59:25 -08:00
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 treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
volume.c afs: Add tracing for cell refcount and active user count 2020-10-16 14:39:21 +01:00
write.c afs: Fix afs_write_end() when called with copied == 0 [ver #3] 2020-11-14 11:51:18 -08:00
xattr.c afs: Fix incorrect freeing of the ACL passed to the YFS ACL store op 2020-11-03 09:53:40 -08:00
xdr_fs.h afs: Fix directory entry size calculation 2021-01-04 12:25:19 +00:00
yfsclient.c afs: Fix warning due to unadvanced marshalling pointer 2020-11-03 09:53:40 -08:00