linux/fs
David Howells 34fa47612b afs: Fix race in async call refcounting
There's a race between afs_make_call() and afs_wake_up_async_call() in the
case that an error is returned from rxrpc_kernel_send_data() after it has
queued the final packet.

afs_make_call() will try and clean up the mess, but the call state may have
been moved on thereby causing afs_process_async_call() to also try and to
delete the call.

Fix this by:

 (1) Getting an extra ref for an asynchronous call for the call itself to
     hold.  This makes sure the call doesn't evaporate on us accidentally
     and will allow the call to be retained by the caller in a future
     patch.  The ref is released on leaving afs_make_call() or
     afs_wait_for_call_to_complete().

 (2) In the event of an error from rxrpc_kernel_send_data():

     (a) Don't set the call state to AFS_CALL_COMPLETE until *after* the
     	 call has been aborted and ended.  This prevents
     	 afs_deliver_to_call() from doing anything with any notifications
     	 it gets.

     (b) Explicitly end the call immediately to prevent further callbacks.

     (c) Cancel any queued async_work and wait for the work if it's
     	 executing.  This allows us to be sure the race won't recur when we
     	 change the state.  We put the work queue's ref on the call if we
     	 managed to cancel it.

     (d) Put the call's ref that we got in (1).  This belongs to us as long
     	 as the call is in state AFS_CALL_CL_REQUESTING.

Fixes: 341f741f04 ("afs: Refcount the afs_call struct")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17 15:17:28 +00:00
..
9p Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-11-01 19:58:52 -07:00
adfs adfs: use timespec64 for time conversion 2018-08-22 10:52:51 -07:00
affs
afs afs: Fix race in async call refcounting 2019-01-17 15:17:28 +00:00
autofs autofs: add strictexpire mount option 2019-01-04 13:13:47 -08:00
befs fix a series of Documentation/ broken file name references 2018-06-15 18:10:01 -03:00
bfs bfs: extra sanity checking and static inode bitmap 2019-01-04 13:13:47 -08:00
btrfs Merge branch 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-01-05 13:25:58 -08:00
cachefiles fscache, cachefiles: remove redundant variable 'cache' 2018-11-30 16:00:58 +00:00
ceph A fairly quiet round: a couple of messenger performance improvements 2019-01-05 13:58:08 -08:00
cifs three fixes, one for stable, one adds the (most secure) SMB3.1.1 dialect to default list requested 2019-01-05 14:05:06 -08:00
coda vfs: change inode times to use struct timespec64 2018-06-05 16:57:31 -07:00
configfs configfs: fix registered group removal 2018-07-17 06:14:07 -07:00
cramfs Make the Cramfs code more robust against filesystem corruptions, 2018-10-30 12:46:25 -07:00
crypto fscrypt: add Adiantum support 2019-01-06 08:36:21 -05:00
debugfs Revert "debugfs: inode: debugfs_create_dir uses mode permission from parent" 2018-06-12 20:52:16 -07:00
devpts devpts: Convert to new IDA API 2018-08-21 23:54:17 -04:00
dlm dlm: fix invalid cluster name warning 2018-12-03 15:30:24 -06:00
ecryptfs ecryptfs_rename(): verify that lower dentries are still OK after lock_rename() 2018-10-09 23:33:17 -04:00
efivarfs efivars: Call guid_parse() against guid_t type of variable 2018-07-22 14:13:44 +02:00
efs
exofs exofs_mount(): fix leaks on failure exits 2018-12-17 18:36:33 -05:00
exportfs exportfs: do not read dentry after free 2018-11-23 09:08:17 -05:00
ext2 \n 2018-12-27 17:00:35 -08:00
ext4 Fix a number of ext4 bugs. 2019-01-06 12:19:23 -08:00
f2fs f2fs-for-4.21-rc1 2018-12-31 09:41:37 -08:00
fat Merge branch 'akpm' (patches from Andrew) 2019-01-05 09:16:18 -08:00
freevxfs
fscache fscache: fix race between enablement and dropping of object 2018-11-30 15:57:31 +00:00
fuse mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
gfs2 File locking changes for v4.21 2018-12-27 17:12:30 -08:00
hfs hfs: do not free node before using 2018-11-30 14:56:14 -08:00
hfsplus hfsplus: return file attributes on statx 2019-01-04 13:13:47 -08:00
hostfs vfs: discard ATTR_ATTR_FLAG 2018-08-17 16:20:28 -07:00
hpfs hpfs: remove unnecessary checks on the value of r when assigning error code 2018-08-25 12:42:33 -07:00
hugetlbfs hugetlbfs: revert "Use i_mmap_rwsem to fix page fault/truncate race" 2019-01-08 17:15:11 -08:00
isofs Update email address 2018-09-29 22:47:48 -04:00
jbd2 jbd2: clean up indentation issue, replace spaces with tab 2018-12-04 00:20:10 -05:00
jffs2 jffs2: Fix use of uninitialized delayed_work, lockdep breakage 2018-12-02 09:20:34 +01:00
jfs jfs: remove redundant dquot_initialize() in jfs_evict_inode() 2018-09-20 09:28:49 -05:00
kernfs kernfs: Improve kernfs_notify() poll notification latency 2018-11-27 11:59:33 +01:00
lockd NFS client updates for Linux 4.21 2019-01-02 16:35:23 -08:00
minix
nfs Merge branch 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-01-05 13:25:58 -08:00
nfs_common
nfsd NFS client updates for Linux 4.21 2019-01-02 16:35:23 -08:00
nilfs2 nilfs2: Use xa_erase_irq 2018-11-05 14:57:05 -05:00
nls
notify fanotify: Use inode_is_open_for_write 2018-12-11 10:55:45 +01:00
ntfs mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
ocfs2 Merge branch 'akpm' (patches from Andrew) 2019-01-05 09:16:18 -08:00
omfs
openpromfs fs/openpromfs: Use of_node_name_eq for node name comparisons 2018-11-18 13:35:19 -08:00
orangefs fs: don't open code lru_to_page() 2019-01-04 13:13:48 -08:00
overlayfs Revert "ovl: relax permission checking on underlying layers" 2018-12-04 11:31:30 +01:00
proc fs/proc/base.c: slightly faster /proc/*/limits 2019-01-04 13:13:45 -08:00
pstore Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
qnx4
qnx6
quota quota: Lock s_umount in exclusive mode for Q_XQUOTA{ON,OFF} quotactls. 2018-12-18 18:29:15 +01:00
ramfs
reiserfs reiserfs: remove workaround code for GCC 3.x 2018-10-31 08:54:14 -07:00
romfs
squashfs Squashfs: Compute expected length from inode size rather than block length 2018-08-02 09:34:02 -07:00
sysfs sysfs: constify sysfs create/remove files harder 2018-12-03 18:18:19 +02:00
sysv sysv: return 'err' instead of 0 in __sysv_write_inode 2018-11-10 08:02:40 -05:00
tracefs tracefs: Annotate tracefs_ops with __ro_after_init 2018-07-31 11:32:44 -04:00
ubifs mm: migrate: drop unused argument of migrate_page_move_mapping() 2018-12-28 12:11:51 -08:00
udf \n 2018-12-27 17:00:35 -08:00
ufs fs/ufs: use ktime_get_real_seconds for sb and cg timestamps 2018-08-17 16:20:27 -07:00
xfs xfs: xfs_fsops: drop useless LIST_HEAD 2018-12-29 10:47:58 -08:00
aio.c Merge branch 'akpm' (patches from Andrew) 2018-12-28 16:55:46 -08:00
anon_inodes.c anon_inode_getfile(): switch to alloc_file_pseudo() 2018-07-12 10:04:27 -04:00
attr.c fs: Fix attr.c kernel-doc 2018-07-03 16:44:45 -04:00
bad_inode.c get rid of 'opened' argument of ->atomic_open() - part 3 2018-07-12 10:04:20 -04:00
binfmt_aout.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
binfmt_elf_fdpic.c treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
binfmt_elf.c signal: Distinguish between kernel_siginfo and siginfo 2018-10-03 16:47:43 +02:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c turn filp_clone_open() into inline wrapper for dentry_open() 2018-07-10 23:29:03 -04:00
binfmt_script.c exec: load_script: don't blindly truncate shebang string 2019-01-04 13:13:47 -08:00
block_dev.c block: don't use un-ordered __set_current_state(TASK_UNINTERRUPTIBLE) 2019-01-02 10:46:03 -08:00
buffer.c fs/: remove caller signal_pending branch predictions 2019-01-04 13:13:48 -08:00
char_dev.c
compat_binfmt_elf.c y2038: globally rename compat_time to old_time32 2018-08-27 14:48:48 +02:00
compat_ioctl.c media updates for v4.20-rc1 2018-10-29 14:29:58 -07:00
compat.c ncpfs: remove compat functionality 2018-06-05 19:23:26 +02:00
coredump.c signal: Distinguish between kernel_siginfo and siginfo 2018-10-03 16:47:43 +02:00
d_path.c
dax.c dax fix 4.21 2018-12-31 09:46:39 -08:00
dcache.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
dcookies.c
direct-io.c Linux 4.20-rc5 2018-12-04 09:38:05 -07:00
drop_caches.c
eventfd.c Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
eventpoll.c Merge branch 'akpm' (patches from Andrew) 2019-01-05 09:16:18 -08:00
exec.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-01-05 13:18:59 -08:00
fcntl.c signal: Distinguish between kernel_siginfo and siginfo 2018-10-03 16:47:43 +02:00
fhandle.c
file_table.c mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
file.c Char/Misc driver patches for 4.21-rc1 2018-12-28 20:54:57 -08:00
filesystems.c
fs_pin.c
fs_struct.c
fs-writeback.c fs: Convert writeback to XArray 2018-10-21 10:46:42 -04:00
inode.c y2038: more syscalls and cleanups 2018-12-28 12:45:04 -08:00
internal.h overlayfs update for 4.19 2018-08-21 18:19:09 -07:00
ioctl.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
iomap.c block: don't use un-ordered __set_current_state(TASK_UNINTERRUPTIBLE) 2019-01-02 10:46:03 -08:00
Kconfig autofs: remove left-over autofs4 stubs 2018-06-11 08:22:34 -07:00
Kconfig.binfmt kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
libfs.c
locks.c locks: fix error in locks_move_blocks() 2019-01-02 20:14:50 -05:00
Makefile autofs: remove left-over autofs4 stubs 2018-06-11 08:22:34 -07:00
mbcache.c treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
mount.h
mpage.c mpage: mpage_readpages() should submit IO as read-ahead 2018-08-17 16:20:29 -07:00
namei.c Revert "vfs: Allow userns root to call mknod on owned filesystems." 2018-12-22 14:18:34 -08:00
namespace.c Merge branch 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-01-05 13:25:58 -08:00
no-block.c
nsfs.c
open.c overlayfs update for 4.19 2018-08-21 18:19:09 -07:00
pipe.c Merge branch 'work.open3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-08-13 19:58:36 -07:00
pnode.c vfs: Suppress MS_* flag defs within the kernel unless explicitly enabled 2018-12-20 16:32:56 +00:00
pnode.h
posix_acl.c
proc_namespace.c
read_write.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
readdir.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
select.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
seq_file.c fs/seq_file.c: simplify seq_file iteration code and interface 2018-08-17 16:20:28 -07:00
signalfd.c signal: Distinguish between kernel_siginfo and siginfo 2018-10-03 16:47:43 +02:00
splice.c splice: don't read more than available pipe space 2018-12-04 08:50:49 -08:00
stack.c
stat.c y2038: Remove newstat family from default syscall set 2018-08-29 15:42:20 +02:00
statfs.c kernel: add kcompat_sys_{f,}statfs64() 2018-07-12 14:49:48 +01:00
super.c mount_fs: suppress MAC on MS_SUBMOUNT as well as MS_KERNMOUNT 2018-12-21 11:51:23 -05:00
sync.c
timerfd.c y2038: globally rename compat_time to old_time32 2018-08-27 14:48:48 +02:00
userfaultfd.c userfaultfd: clear flag if remap event not enabled 2018-12-28 12:11:51 -08:00
utimes.c y2038: utimes: Rework #ifdef guards for compat syscalls 2018-08-29 15:42:23 +02:00
xattr.c sysfs: Do not return POSIX ACL xattrs via listxattr 2018-09-18 07:30:48 -04:00