commit ea60ed6fcf29eebc78f2ce91491e6309ee005a01 upstream.
KASAN reports a use-after-free when running xfstest generic/531, with the
following trace:
[ 293.903362] kasan_report+0xe/0x20
[ 293.903365] rb_erase+0x1f/0x790
[ 293.903370] __ceph_remove_cap+0x201/0x370
[ 293.903375] __ceph_remove_caps+0x4b/0x70
[ 293.903380] ceph_evict_inode+0x4e/0x360
[ 293.903386] evict+0x169/0x290
[ 293.903390] __dentry_kill+0x16f/0x250
[ 293.903394] dput+0x1c6/0x440
[ 293.903398] __fput+0x184/0x330
[ 293.903404] task_work_run+0xb9/0xe0
[ 293.903410] exit_to_usermode_loop+0xd3/0xe0
[ 293.903413] do_syscall_64+0x1a0/0x1c0
[ 293.903417] entry_SYSCALL_64_after_hwframe+0x44/0xa9
This happens because __ceph_remove_cap() may queue a cap release
(__ceph_queue_cap_release) which can be scheduled before that cap is
removed from the inode list with
rb_erase(&cap->ci_node, &ci->i_caps);
And, when this finally happens, the use-after-free will occur.
This can be fixed by removing the cap from the inode list before being
removed from the session list, and thus eliminating the risk of an UAF.
Cc: stable@vger.kernel.org
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 750670341a24cb714e624e0fd7da30900ad93752 ]
When filling an inode with info from the MDS, i_blkbits is being
initialized using fl_stripe_unit, which contains the stripe unit in
bytes. Unfortunately, this doesn't make sense for directories as they
have fl_stripe_unit set to '0'. This means that i_blkbits will be set
to 0xff, causing an UBSAN undefined behaviour in i_blocksize():
UBSAN: Undefined behaviour in ./include/linux/fs.h:731:12
shift exponent 255 is too large for 32-bit type 'int'
Fix this by initializing i_blkbits to CEPH_BLOCK_SHIFT if fl_stripe_unit
is zero.
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 86968ef21596515958d5f0a40233d02be78ecec0 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 749607731e26dfb2558118038c40e9c0c80d23b5 ]
This barrier only applies to the read-modify-write operations; in
particular, it does not apply to the atomic64_set() primitive.
Replace the barrier with an smp_mb().
Fixes: fdd4e15838e59 ("ceph: rework dcache readdir")
Reported-by: "Paul E. McKenney" <paulmck@linux.ibm.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 00abf69dd24f4444d185982379c5cc3bb7b6d1fc upstream.
xfstest generic/452 was triggering a "Busy inodes after umount" warning.
ceph was allowing the mount to go read-only without first flushing out
dirty inodes in the cache. Ensure we sync out the filesystem before
allowing a remount to proceed.
Cc: stable@vger.kernel.org
Link: http://tracker.ceph.com/issues/39571
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit daf5cc27eed99afdea8d96e71b89ba41f5406ef6 ]
free the symlink body after the same RCU delay we have for freeing the
struct inode itself, so that traversal during RCU pathwalk wouldn't step
into freed memory.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
commit 37659182bff1eeaaeadcfc8f853c6d2b6dbc3f47 upstream.
We missed two places that i_wrbuffer_ref_head, i_wr_ref, i_dirty_caps
and i_flushing_caps may change. When they are all zeros, we should free
i_head_snapc.
Cc: stable@vger.kernel.org
Link: https://tracker.ceph.com/issues/38224
Reported-and-tested-by: Luis Henriques <lhenriques@suse.com>
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
