linux-stable.git/fs, branch v6.7.3

cifs: fix stray unlock in cifs_chan_skip_or_disable

2024-02-01T00:21:20+00:00

[ Upstream commit 993d1c346b1a51ac41b2193609a0d4e51e9748f4 ]

A recent change moved the code that decides to skip
a channel or disable multichannel entirely, into a
helper function.

During this, a mutex_unlock of the session_mutex
should have been removed. Doing that here.

Fixes: f591062bdbf4 ("cifs: handle servers that still advertise multichannel after disabling")
Signed-off-by: Shyam Prasad N 
Signed-off-by: Steve French 
Signed-off-by: Sasha Levin

btrfs: zoned: optimize hint byte for zoned allocator

2024-02-01T00:21:16+00:00

[ Upstream commit 02444f2ac26eae6385a65fcd66915084d15dffba ]

Writing sequentially to a huge file on btrfs on a SMR HDD revealed a
decline of the performance (220 MiB/s to 30 MiB/s after 500 minutes).

The performance goes down because of increased latency of the extent
allocation, which is induced by a traversing of a lot of full block groups.

So, this patch optimizes the ffe_ctl->hint_byte by choosing a block group
with sufficient size from the active block group list, which does not
contain full block groups.

After applying the patch, the performance is maintained well.

Fixes: 2eda57089ea3 ("btrfs: zoned: implement sequential extent allocation")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Johannes Thumshirn 
Signed-off-by: Naohiro Aota 
Signed-off-by: David Sterba 
Signed-off-by: Sasha Levin

btrfs: zoned: factor out prepare_allocation_zoned()

2024-02-01T00:21:16+00:00

[ Upstream commit b271fee9a41ca1474d30639fd6cc912c9901d0f8 ]

Factor out prepare_allocation_zoned() for further extension. While at
it, optimize the if-branch a bit.

Reviewed-by: Johannes Thumshirn 
Signed-off-by: Naohiro Aota 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba 
Stable-dep-of: 02444f2ac26e ("btrfs: zoned: optimize hint byte for zoned allocator")
Signed-off-by: Sasha Levin

xfs: read only mounts with fsopen mount API are busted

2024-02-01T00:21:12+00:00

commit d8d222e09dab84a17bb65dda4b94d01c565f5327 upstream.

Recently xfs/513 started failing on my test machines testing "-o
ro,norecovery" mount options. This was being emitted in dmesg:

[ 9906.932724] XFS (pmem0): no-recovery mounts must be read-only.

Turns out, readonly mounts with the fsopen()/fsconfig() mount API
have been busted since day zero. It's only taken 5 years for debian
unstable to start using this "new" mount API, and shortly after this
I noticed xfs/513 had started to fail as per above.

The syscall trace is:

fsopen("xfs", FSOPEN_CLOEXEC)           = 3
mount_setattr(-1, NULL, 0, NULL, 0)     = -1 EINVAL (Invalid argument)
.....
fsconfig(3, FSCONFIG_SET_STRING, "source", "/dev/pmem0", 0) = 0
fsconfig(3, FSCONFIG_SET_FLAG, "ro", NULL, 0) = 0
fsconfig(3, FSCONFIG_SET_FLAG, "norecovery", NULL, 0) = 0
fsconfig(3, FSCONFIG_CMD_CREATE, NULL, NULL, 0) = -1 EINVAL (Invalid argument)
close(3)                                = 0

Showing that the actual mount instantiation (FSCONFIG_CMD_CREATE) is
what threw out the error.

During mount instantiation, we call xfs_fs_validate_params() which
does:

        /* No recovery flag requires a read-only mount */
        if (xfs_has_norecovery(mp) && !xfs_is_readonly(mp)) {
                xfs_warn(mp, "no-recovery mounts must be read-only.");
                return -EINVAL;
        }

and xfs_is_readonly() checks internal mount flags for read only
state. This state is set in xfs_init_fs_context() from the
context superblock flag state:

        /*
         * Copy binary VFS mount flags we are interested in.
         */
        if (fc->sb_flags & SB_RDONLY)
                set_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);

With the old mount API, all of the VFS specific superblock flags
had already been parsed and set before xfs_init_fs_context() is
called, so this all works fine.

However, in the brave new fsopen/fsconfig world,
xfs_init_fs_context() is called from fsopen() context, before any
VFS superblock have been set or parsed. Hence if we use fsopen(),
the internal XFS readonly state is *never set*. Hence anything that
depends on xfs_is_readonly() actually returning true for read only
mounts is broken if fsopen() has been used to mount the filesystem.

Fix this by moving this internal state initialisation to
xfs_fs_fill_super() before we attempt to validate the parameters
that have been set prior to the FSCONFIG_CMD_CREATE call being made.

Signed-off-by: Dave Chinner 
Fixes: 73e5fff98b64 ("xfs: switch to use the new mount-api")
cc: stable@vger.kernel.org
Reviewed-by: Christoph Hellwig 
Signed-off-by: Chandan Babu R 
Signed-off-by: Greg Kroah-Hartman

ksmbd: fix global oob in ksmbd_nl_policy

2024-02-01T00:21:12+00:00

commit ebeae8adf89d9a82359f6659b1663d09beec2faa upstream.

Similar to a reported issue (check the commit b33fb5b801c6 ("net:
qualcomm: rmnet: fix global oob in rmnet_policy"), my local fuzzer finds
another global out-of-bounds read for policy ksmbd_nl_policy. See bug
trace below:

==================================================================
BUG: KASAN: global-out-of-bounds in validate_nla lib/nlattr.c:386 [inline]
BUG: KASAN: global-out-of-bounds in __nla_validate_parse+0x24af/0x2750 lib/nlattr.c:600
Read of size 1 at addr ffffffff8f24b100 by task syz-executor.1/62810

CPU: 0 PID: 62810 Comm: syz-executor.1 Tainted: G                 N 6.1.0 #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
 
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x8b/0xb3 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x172/0x475 mm/kasan/report.c:395
 kasan_report+0xbb/0x1c0 mm/kasan/report.c:495
 validate_nla lib/nlattr.c:386 [inline]
 __nla_validate_parse+0x24af/0x2750 lib/nlattr.c:600
 __nla_parse+0x3e/0x50 lib/nlattr.c:697
 __nlmsg_parse include/net/netlink.h:748 [inline]
 genl_family_rcv_msg_attrs_parse.constprop.0+0x1b0/0x290 net/netlink/genetlink.c:565
 genl_family_rcv_msg_doit+0xda/0x330 net/netlink/genetlink.c:734
 genl_family_rcv_msg net/netlink/genetlink.c:833 [inline]
 genl_rcv_msg+0x441/0x780 net/netlink/genetlink.c:850
 netlink_rcv_skb+0x14f/0x410 net/netlink/af_netlink.c:2540
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:861
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x54e/0x800 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x930/0xe50 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0x154/0x190 net/socket.c:734
 ____sys_sendmsg+0x6df/0x840 net/socket.c:2482
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2536
 __sys_sendmsg+0xf3/0x1c0 net/socket.c:2565
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fdd66a8f359
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fdd65e00168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fdd66bbcf80 RCX: 00007fdd66a8f359
RDX: 0000000000000000 RSI: 0000000020000500 RDI: 0000000000000003
RBP: 00007fdd66ada493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc84b81aff R14: 00007fdd65e00300 R15: 0000000000022000
 

The buggy address belongs to the variable:
 ksmbd_nl_policy+0x100/0xa80

The buggy address belongs to the physical page:
page:0000000034f47940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1ccc4b
flags: 0x200000000001000(reserved|node=0|zone=2)
raw: 0200000000001000 ffffea00073312c8 ffffea00073312c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffffffff8f24b000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffffff8f24b080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffffff8f24b100: f9 f9 f9 f9 00 00 f9 f9 f9 f9 f9 f9 00 00 07 f9
                   ^
 ffffffff8f24b180: f9 f9 f9 f9 00 05 f9 f9 f9 f9 f9 f9 00 00 00 05
 ffffffff8f24b200: f9 f9 f9 f9 00 00 03 f9 f9 f9 f9 f9 00 00 04 f9
==================================================================

To fix it, add a placeholder named __KSMBD_EVENT_MAX and let
KSMBD_EVENT_MAX to be its original value - 1 according to what other
netlink families do. Also change two sites that refer the
KSMBD_EVENT_MAX to correct value.

Cc: stable@vger.kernel.org
Fixes: 0626e6641f6b ("cifsd: add server handler for central processing and tranport layers")
Signed-off-by: Lin Ma 
Acked-by: Namjae Jeon 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

ovl: mark xwhiteouts directory with overlay.opaque='x'

2024-02-01T00:21:11+00:00

commit 420332b94119cdc7db4477cc88484691cb92ae71 upstream.

An opaque directory cannot have xwhiteouts, so instead of marking an
xwhiteouts directory with a new xattr, overload overlay.opaque xattr
for marking both opaque dir ('y') and xwhiteouts dir ('x').

This is more efficient as the overlay.opaque xattr is checked during
lookup of directory anyway.

This also prevents unnecessary checking the xattr when reading a
directory without xwhiteouts, i.e. most of the time.

Note that the xwhiteouts marker is not checked on the upper layer and
on the last layer in lowerstack, where xwhiteouts are not expected.

Fixes: bc8df7a3dc03 ("ovl: Add an alternative type of whiteout")
Cc:  # v6.7
Reviewed-by: Alexander Larsson 
Tested-by: Alexander Larsson 
Signed-off-by: Amir Goldstein 
Signed-off-by: Greg Kroah-Hartman

nfsd: fix RELEASE_LOCKOWNER

2024-02-01T00:21:11+00:00

commit edcf9725150e42beeca42d085149f4c88fa97afd upstream.

The test on so_count in nfsd4_release_lockowner() is nonsense and
harmful.  Revert to using check_for_locks(), changing that to not sleep.

First: harmful.
As is documented in the kdoc comment for nfsd4_release_lockowner(), the
test on so_count can transiently return a false positive resulting in a
return of NFS4ERR_LOCKS_HELD when in fact no locks are held.  This is
clearly a protocol violation and with the Linux NFS client it can cause
incorrect behaviour.

If RELEASE_LOCKOWNER is sent while some other thread is still
processing a LOCK request which failed because, at the time that request
was received, the given owner held a conflicting lock, then the nfsd
thread processing that LOCK request can hold a reference (conflock) to
the lock owner that causes nfsd4_release_lockowner() to return an
incorrect error.

The Linux NFS client ignores that NFS4ERR_LOCKS_HELD error because it
never sends NFS4_RELEASE_LOCKOWNER without first releasing any locks, so
it knows that the error is impossible.  It assumes the lock owner was in
fact released so it feels free to use the same lock owner identifier in
some later locking request.

When it does reuse a lock owner identifier for which a previous RELEASE
failed, it will naturally use a lock_seqid of zero.  However the server,
which didn't release the lock owner, will expect a larger lock_seqid and
so will respond with NFS4ERR_BAD_SEQID.

So clearly it is harmful to allow a false positive, which testing
so_count allows.

The test is nonsense because ... well... it doesn't mean anything.

so_count is the sum of three different counts.
1/ the set of states listed on so_stateids
2/ the set of active vfs locks owned by any of those states
3/ various transient counts such as for conflicting locks.

When it is tested against '2' it is clear that one of these is the
transient reference obtained by find_lockowner_str_locked().  It is not
clear what the other one is expected to be.

In practice, the count is often 2 because there is precisely one state
on so_stateids.  If there were more, this would fail.

In my testing I see two circumstances when RELEASE_LOCKOWNER is called.
In one case, CLOSE is called before RELEASE_LOCKOWNER.  That results in
all the lock states being removed, and so the lockowner being discarded
(it is removed when there are no more references which usually happens
when the lock state is discarded).  When nfsd4_release_lockowner() finds
that the lock owner doesn't exist, it returns success.

The other case shows an so_count of '2' and precisely one state listed
in so_stateid.  It appears that the Linux client uses a separate lock
owner for each file resulting in one lock state per lock owner, so this
test on '2' is safe.  For another client it might not be safe.

So this patch changes check_for_locks() to use the (newish)
find_any_file_locked() so that it doesn't take a reference on the
nfs4_file and so never calls nfsd_file_put(), and so never sleeps.  With
this check is it safe to restore the use of check_for_locks() rather
than testing so_count against the mysterious '2'.

Fixes: ce3c4ad7f4ce ("NFSD: Fix possible sleep during nfsd4_release_lockowner()")
Signed-off-by: NeilBrown 
Reviewed-by: Jeff Layton 
Cc: stable@vger.kernel.org # v6.2+
Signed-off-by: Chuck Lever 
Signed-off-by: Greg Kroah-Hartman

exec: Fix error handling in begin_new_exec()

2024-02-01T00:21:11+00:00

commit 84c39ec57d409e803a9bb6e4e85daf1243e0e80b upstream.

If get_unused_fd_flags() fails, the error handling is incomplete because
bprm->cred is already set to NULL, and therefore free_bprm will not
unlock the cred_guard_mutex. Note there are two error conditions which
end up here, one before and one after bprm->cred is cleared.

Fixes: b8a61c9e7b4a ("exec: Generic execfd support")
Signed-off-by: Bernd Edlinger 
Acked-by: Eric W. Biederman 
Link: https://lore.kernel.org/r/AS8P193MB128517ADB5EFF29E04389EDAE4752@AS8P193MB1285.EURP193.PROD.OUTLOOK.COM
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook 
Signed-off-by: Greg Kroah-Hartman

btrfs: don't abort filesystem when attempting to snapshot deleted subvolume

2024-02-01T00:21:11+00:00

commit 7081929ab2572920e94d70be3d332e5c9f97095a upstream.

If the source file descriptor to the snapshot ioctl refers to a deleted
subvolume, we get the following abort:

  BTRFS: Transaction aborted (error -2)
  WARNING: CPU: 0 PID: 833 at fs/btrfs/transaction.c:1875 create_pending_snapshot+0x1040/0x1190 [btrfs]
  Modules linked in: pata_acpi btrfs ata_piix libata scsi_mod virtio_net blake2b_generic xor net_failover virtio_rng failover scsi_common rng_core raid6_pq libcrc32c
  CPU: 0 PID: 833 Comm: t_snapshot_dele Not tainted 6.7.0-rc6 #2
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014
  RIP: 0010:create_pending_snapshot+0x1040/0x1190 [btrfs]
  RSP: 0018:ffffa09c01337af8 EFLAGS: 00010282
  RAX: 0000000000000000 RBX: ffff9982053e7c78 RCX: 0000000000000027
  RDX: ffff99827dc20848 RSI: 0000000000000001 RDI: ffff99827dc20840
  RBP: ffffa09c01337c00 R08: 0000000000000000 R09: ffffa09c01337998
  R10: 0000000000000003 R11: ffffffffb96da248 R12: fffffffffffffffe
  R13: ffff99820535bb28 R14: ffff99820b7bd000 R15: ffff99820381ea80
  FS:  00007fe20aadabc0(0000) GS:ffff99827dc00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000559a120b502f CR3: 00000000055b6000 CR4: 00000000000006f0
  Call Trace:
   
   ? create_pending_snapshot+0x1040/0x1190 [btrfs]
   ? __warn+0x81/0x130
   ? create_pending_snapshot+0x1040/0x1190 [btrfs]
   ? report_bug+0x171/0x1a0
   ? handle_bug+0x3a/0x70
   ? exc_invalid_op+0x17/0x70
   ? asm_exc_invalid_op+0x1a/0x20
   ? create_pending_snapshot+0x1040/0x1190 [btrfs]
   ? create_pending_snapshot+0x1040/0x1190 [btrfs]
   create_pending_snapshots+0x92/0xc0 [btrfs]
   btrfs_commit_transaction+0x66b/0xf40 [btrfs]
   btrfs_mksubvol+0x301/0x4d0 [btrfs]
   btrfs_mksnapshot+0x80/0xb0 [btrfs]
   __btrfs_ioctl_snap_create+0x1c2/0x1d0 [btrfs]
   btrfs_ioctl_snap_create_v2+0xc4/0x150 [btrfs]
   btrfs_ioctl+0x8a6/0x2650 [btrfs]
   ? kmem_cache_free+0x22/0x340
   ? do_sys_openat2+0x97/0xe0
   __x64_sys_ioctl+0x97/0xd0
   do_syscall_64+0x46/0xf0
   entry_SYSCALL_64_after_hwframe+0x6e/0x76
  RIP: 0033:0x7fe20abe83af
  RSP: 002b:00007ffe6eff1360 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fe20abe83af
  RDX: 00007ffe6eff23c0 RSI: 0000000050009417 RDI: 0000000000000003
  RBP: 0000000000000003 R08: 0000000000000000 R09: 00007fe20ad16cd0
  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
  R13: 00007ffe6eff13c0 R14: 00007fe20ad45000 R15: 0000559a120b6d58
   
  ---[ end trace 0000000000000000 ]---
  BTRFS: error (device vdc: state A) in create_pending_snapshot:1875: errno=-2 No such entry
  BTRFS info (device vdc: state EA): forced readonly
  BTRFS warning (device vdc: state EA): Skipping commit of aborted transaction.
  BTRFS: error (device vdc: state EA) in cleanup_transaction:2055: errno=-2 No such entry

This happens because create_pending_snapshot() initializes the new root
item as a copy of the source root item. This includes the refs field,
which is 0 for a deleted subvolume. The call to btrfs_insert_root()
therefore inserts a root with refs == 0. btrfs_get_new_fs_root() then
finds the root and returns -ENOENT if refs == 0, which causes
create_pending_snapshot() to abort.

Fix it by checking the source root's refs before attempting the
snapshot, but after locking subvol_sem to avoid racing with deletion.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Sweet Tea Dorminy 
Reviewed-by: Anand Jain 
Signed-off-by: Omar Sandoval 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman

btrfs: defrag: reject unknown flags of btrfs_ioctl_defrag_range_args

2024-02-01T00:21:11+00:00

commit 173431b274a9a54fc10b273b46e67f46bcf62d2e upstream.

Add extra sanity check for btrfs_ioctl_defrag_range_args::flags.

This is not really to enhance fuzzing tests, but as a preparation for
future expansion on btrfs_ioctl_defrag_range_args.

In the future we're going to add new members, allowing more fine tuning
for btrfs defrag.  Without the -ENONOTSUPP error, there would be no way
to detect if the kernel supports those new defrag features.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana 
Signed-off-by: Qu Wenruo 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman