linux/fs/ceph
Luis Henriques 86968ef215 ceph: fix buffer free while holding i_ceph_lock in __ceph_setxattr()
Calling ceph_buffer_put() in __ceph_setxattr() may end up freeing the
i_xattrs.prealloc_blob buffer while holding the i_ceph_lock.  This can be
fixed by postponing the call until later, when the lock is released.

The following backtrace was triggered by fstests generic/117.

  BUG: sleeping function called from invalid context at mm/vmalloc.c:2283
  in_atomic(): 1, irqs_disabled(): 0, pid: 650, name: fsstress
  3 locks held by fsstress/650:
   #0: 00000000870a0fe8 (sb_writers#8){.+.+}, at: mnt_want_write+0x20/0x50
   #1: 00000000ba0c4c74 (&type->i_mutex_dir_key#6){++++}, at: vfs_setxattr+0x55/0xa0
   #2: 000000008dfbb3f2 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: __ceph_setxattr+0x297/0x810
  CPU: 1 PID: 650 Comm: fsstress Not tainted 5.2.0+ #437
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014
  Call Trace:
   dump_stack+0x67/0x90
   ___might_sleep.cold+0x9f/0xb1
   vfree+0x4b/0x60
   ceph_buffer_release+0x1b/0x60
   __ceph_setxattr+0x2b4/0x810
   __vfs_setxattr+0x66/0x80
   __vfs_setxattr_noperm+0x59/0xf0
   vfs_setxattr+0x81/0xa0
   setxattr+0x115/0x230
   ? filename_lookup+0xc9/0x140
   ? rcu_read_lock_sched_held+0x74/0x80
   ? rcu_sync_lockdep_assert+0x2e/0x60
   ? __sb_start_write+0x142/0x1a0
   ? mnt_want_write+0x20/0x50
   path_setxattr+0xba/0xd0
   __x64_sys_lsetxattr+0x24/0x30
   do_syscall_64+0x50/0x1c0
   entry_SYSCALL_64_after_hwframe+0x49/0xbe
  RIP: 0033:0x7ff23514359a

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-08-22 10:47:41 +02:00
..
acl.c ceph: rename struct ceph_acls_info to ceph_acl_sec_ctx 2019-07-08 14:01:42 +02:00
addr.c ceph: increment change_attribute on local changes 2019-07-08 14:01:44 +02:00
cache.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 188 2019-05-30 11:29:21 -07:00
cache.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 188 2019-05-30 11:29:21 -07:00
caps.c ceph: more precise CEPH_CLIENT_CAPS_PENDING_CAPSNAP 2019-07-08 14:01:44 +02:00
ceph_frag.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debugfs.c Lots of exciting things this time! 2019-07-18 11:05:25 -07:00
dir.c Merge branch 'work.dcache2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-20 09:15:51 -07:00
export.c ceph: fix warning PTR_ERR_OR_ZERO can be used 2019-07-08 14:01:42 +02:00
file.c Lots of exciting things this time! 2019-07-18 11:05:25 -07:00
inode.c ceph: use generic_delete_inode() for ->drop_inode 2019-07-08 14:01:45 +02:00
ioctl.c libceph, ceph: move ceph_calc_file_object_mapping() to striper.c 2018-04-02 10:12:43 +02:00
ioctl.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig ceph: add selinux support 2019-07-08 14:01:42 +02:00
locks.c ceph: remove duplicated filelock ref increase 2019-05-07 19:22:36 +02:00
Makefile ceph: quota: add initial infrastructure to support cephfs quotas 2018-04-02 11:17:51 +02:00
mds_client.c ceph: add change_attr field to ceph_inode_info 2019-07-08 14:01:43 +02:00
mds_client.h ceph: add change_attr field to ceph_inode_info 2019-07-08 14:01:43 +02:00
mdsmap.c ceph: have MDS map decoding use entity_addr_t decoder 2019-07-08 14:01:43 +02:00
quota.c ceph: fix infinite loop in get_quota_realm() 2019-07-08 14:01:42 +02:00
snap.c ceph: handle change_attr in cap messages 2019-07-08 14:01:43 +02:00
strings.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
super.c Lots of exciting things this time! 2019-07-18 11:05:25 -07:00
super.h Lots of exciting things this time! 2019-07-18 11:05:25 -07:00
xattr.c ceph: fix buffer free while holding i_ceph_lock in __ceph_setxattr() 2019-08-22 10:47:41 +02:00