David Howells e36bc9930d afs: Fix directory permissions check ...

[ Upstream commit 378831e4daec75fbba6d3612bcf3b4dd00ddbf08 ]

Doing faccessat("/afs/some/directory", 0) triggers a BUG in the permissions
check code.

Fix this by just removing the BUG section.  If no permissions are asked
for, just return okay if the file exists.

Also:

 (1) Split up the directory check so that it has separate if-statements
     rather than if-else-if (e.g. checking for MAY_EXEC shouldn't skip the
     check for MAY_READ and MAY_WRITE).

 (2) Check for MAY_CHDIR as MAY_EXEC.

Without the main fix, the following BUG may occur:

 kernel BUG at fs/afs/security.c:386!
 invalid opcode: 0000 [#1] SMP PTI
 ...
 RIP: 0010:afs_permission+0x19d/0x1a0 [kafs]
 ...
 Call Trace:
  ? inode_permission+0xbe/0x180
  ? do_faccessat+0xdc/0x270
  ? do_syscall_64+0x60/0x1f0
  ? entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: 00d3b7a4533e ("[AFS]: Add security support.")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2018-07-08 15:30:51 +02:00

..

afs_cm.h

…

afs_fs.h

…

afs_vl.h

…

afs.h

afs: Support interacting with multiple user namespaces

2013-02-13 06:00:51 -08:00

cache.c

fscache: remove unused ->now_uncached callback

2017-09-06 17:27:26 -07:00

callback.c

afs: Migrate vlocation fields to 64-bit

2017-03-16 16:27:46 +00:00

cell.c

FS-Cache: Provide the ability to enable/disable cookies

2013-09-27 18:40:25 +01:00

cmservice.c

afs: Connect up the CB.ProbeUuid

2017-12-14 09:53:15 +01:00

dir.c

afs: Add metadata xattrs

2017-07-09 14:40:12 -07:00

file.c

afs: Add metadata xattrs

2017-07-09 14:40:12 -07:00

flock.c

fs/afs/flock: Remove deprecated create_singlethread_workqueue

2016-09-04 21:41:39 +01:00

fsclient.c

afs: Populate and use client modification time

2017-03-16 16:27:47 +00:00

inode.c

afs: Add metadata xattrs

2017-07-09 14:40:12 -07:00

internal.h

afs: Add metadata xattrs

2017-07-09 14:40:12 -07:00

Kconfig

fs/afs: remove depends on CONFIG_EXPERIMENTAL

2013-01-21 14:39:04 -08:00

main.c

uuid,afs: move struct uuid_v1 back into afs

2017-06-05 16:56:34 +02:00

Makefile

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

misc.c

rxrpc: Move the packet.h include file into net/rxrpc/

2017-07-21 11:00:20 +01:00

mntpt.c

afs: Add metadata xattrs

2017-07-09 14:40:12 -07:00

netdevices.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

proc.c

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

2016-12-24 11:46:01 -08:00

rxrpc.c

afs: Fix the non-encryption of calls

2018-06-21 04:02:59 +09:00

security.c

afs: Fix directory permissions check

2018-07-08 15:30:51 +02:00

server.c

afs: Migrate vlocation fields to 64-bit

2017-03-16 16:27:46 +00:00

super.c

Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2017-07-15 12:00:42 -07:00

vlclient.c

afs: Kill afs_wait_mode

2017-01-09 11:10:02 +00:00

vlocation.c

afs: Migrate vlocation fields to 64-bit

2017-03-16 16:27:46 +00:00

vnode.c

afs: Kill afs_wait_mode

2017-01-09 11:10:02 +00:00

volume.c

afs: Convert to separately allocated bdi

2017-04-20 12:09:55 -06:00

write.c

afs: Fix missing error handling in afs_write_end()

2018-03-03 10:24:32 +01:00

xattr.c

afs: Add metadata xattrs

2017-07-09 14:40:12 -07:00