open_tree(..., OPEN_TREE_NAMESPACE) and
fsmount(..., FSMOUNT_NAMESPACE, ...) currently work on non-directories,
like regular files. That's bad for two reasons:
- It ends up mounting a regular file over the inherited namespace root,
which is a directory; mounting a non-directory over a directory is
normally explicitly forbidden, see for example do_move_mount()
- It causes setns() on the new namespace to set the cwd to a regular
file, which the rest of VFS does not expect
Fix it by restricting create_new_namespace() (which is used by both of
these flags) to directories.
Leave the behavior for OPEN_TREE_CLONE as-is, that seems unproblematic.
Fixes: 9b8a0ba682 ("mount: add OPEN_TREE_NAMESPACE")
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs fixes from Christian Brauner:
- Fix error handling in ovl_cache_get()
- Tighten access checks for exited tasks in pidfd_getfd()
- Fix selftests leak in __wait_for_test()
- Limit FUSE_NOTIFY_RETRIEVE to uptodate folios
- Reject fuse_notify() pagecache ops on directories
- Clear JOBCTL_PENDING_MASK for caller in zap_other_threads()
- Fix failure to unlock in nfsd4_create_file()
- Fix pointer arithmetic in qnx6 directory iteration
- Fix UAF due to unlocked ->mnt_ns read in may_decode_fh()
- Avoid potential null folio->mapping deref during iomap error
reporting
* tag 'vfs-7.1-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
iomap: avoid potential null folio->mapping deref during error reporting
fhandle: fix UAF due to unlocked ->mnt_ns read in may_decode_fh()
fs/qnx6: fix pointer arithmetic in directory iteration
VFS: fix possible failure to unlock in nfsd4_create_file()
signal: clear JOBCTL_PENDING_MASK for caller in zap_other_threads()
fuse: reject fuse_notify() pagecache ops on directories
fuse: limit FUSE_NOTIFY_RETRIEVE to uptodate folios
selftests: harness: fix pidfd leak in __wait_for_test
pidfd: refuse access to tasks that have started exiting harder
ovl: keep err zero after successful ovl_cache_get()
Pull NFS client fix from Trond Myklebust:
- Fix a use after free in nfs_write_completion
* tag 'nfs-for-7.1-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFS: write_completion: dereference loop-local req, not hdr->req
Pull xfs fixes from Carlos Maiolino:
"A collection of fixes mostly for the RT device, including a small
refactor that has no functional change"
* tag 'xfs-fixes-7.1-rc7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: Remove mention of PageWriteback
xfs: abort mount if xfs_fs_reserve_ag_blocks fails
xfs: factor rtgroup geom write pointer reporting into a helper
xfs: drop the RTG reference later in xfs_ioc_rtgroup_geometry
xfs: fix rtgroup cleanup in CoW fork repair
xfs: fix error returns in CoW fork repair
xfs: fix overlapping extents returned for pNFS LAYOUTGET
xfs: fix use of uninitialized imap in xfs_fs_map_blocks error path
xfs: handle racing deletions in xfs_zone_gc_iter_irec
Pull erofs fixes from Gao Xiang:
- Fix a UAF of sbi->sync_decompress when compressed I/Os
race with unmount
- Fix a regression introduced this development cycle that
incorrectly rejects multiple-algorithm images
* tag 'erofs-for-7.1-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: fix EFSCORRUPTED on multi-algorithm images in z_erofs_map_sanity_check()
erofs: fix use-after-free on sbi->sync_decompress
When a buffered read fails, iomap_finish_folio_read() reports the error
with fserror_report_io(folio->mapping->host, ...). This is called after
ifs->read_bytes_pending has been decremented by the bytes attempted to
be read.
For a folio split across multiple read completions, the folio is only
guaranteed to stay locked while read_bytes_pending > 0. Once
iomap_finish_folio_read() decrements read_bytes_pending, another
in-flight read can complete and end the read on the folio, which unlocks
it. This allows truncate logic to run and detach the folio (set
folio->mapping to NULL). The error reporting path then can dereference a
NULL folio->mapping. As reported by Sam Sun, this is the race that can
occur:
CPU0: failed completion CPU1: final completion CPU2: truncate
----------------------- ---------------------- --------------
read_bytes_pending -= len
finished = false
/* preempted before
fserror_report_io() */
read_bytes_pending -= len
finished = true
folio_end_read()
truncate clears
folio->mapping
fserror_report_io(
folio->mapping->host, ...)
^ NULL deref
Fix this by reporting the error first before decrementing
ifs->read_bytes_pending.
Fixes: a9d573ee88 ("iomap: report file I/O errors to the VFS")
Cc: stable@vger.kernel.org
Reported-by: Sam Sun <samsun1006219@gmail.com>
Closes: https://lore.kernel.org/linux-fsdevel/CAEkJfYPhWdd59RKmuNLJg-bkypHz7xiOwaWyNVu3A8CUqQCnvg@mail.gmail.com/
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Link: https://patch.msgid.link/20260604011858.2297561-1-joannelkoong@gmail.com
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
may_decode_fh() accesses mount::mnt_ns without holding any locks; that
means the mount can concurrently be unmounted, and the mnt_namespace can
concurrently be freed after an RCU grace period.
This race can happens as follows, assuming that the mount point was
created by open_tree(..., OPEN_TREE_CLONE):
thread 1 thread 2 RCU
__do_sys_open_by_handle_at
do_handle_open
handle_to_path
may_decode_fh
is_mounted
[mount::mnt_ns access]
[mount::mnt_ns access]
__do_sys_close
fput_close_sync
__fput
dissolve_on_fput
umount_tree
class_namespace_excl_destructor
namespace_unlock
free_mnt_ns
mnt_ns_tree_remove
call_rcu(mnt_ns_release_rcu)
mnt_ns_release_rcu
mnt_ns_release
kfree
[mnt_namespace::user_ns access] **UAF**
Fix it by taking rcu_read_lock() around the mount::mnt_ns access, like
in __prepend_path().
Additionally, document the semantics of mount::mnt_ns, and use WRITE_ONCE()
for writers that can race with lockless readers.
This bug is unreachable unless one of the following is set:
- CONFIG_PREEMPTION
- CONFIG_RCU_STRICT_GRACE_PERIOD
because it requires an RCU grace period to happen during a syscall without
an explicit preemption.
This doesn't seem to have interesting security impact; worst-case, it could
leak the result of an integer comparison to userspace (from the level
check in cap_capable()), cause an endless loop, or crash the kernel by
dereferencing an invalid address.
Fixes: 620c266f39 ("fhandle: relax open_by_handle_at() permission checks")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Link: https://patch.msgid.link/20260603-vfs-fhandle-uaf-fix-v2-1-d05db76a5084@google.com
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
5d3869a41f ("NFS: fix writeback in presence of errors") introduced
a dereference of hdr->req->wb_lock_context in nfs_write_completion's
per-request loop. hdr->req is set once at nfs_pgheader_init() time
and is not refcount-protected for the lifetime of the loop; when hdr
aggregates requests from multiple page groups (common under heavy
NFSv3 writeback), a parallel COMMIT on hdr->req's group can drop the
last reference and free it while the outer loop is still iterating
requests from other groups. KASAN catches this as an 8-byte read at
offset +24 of a freed nfs_page slab object (wb_lock_context).
All requests in a given pgio share the same open_context, so reading
the loop-local req's wb_lock_context yields the same value and is
safe -- req is still on hdr->pages and holds its writeback kref
through the commit branch.
Caught with kasan:
BUG: KASAN: slab-use-after-free in nfs_write_completion+0x8f8/0xa50 [nfs]
Read of size 8 at addr ffff888118af2058 by task kworker/u16:16/122062
CPU: 2 UID: 0 PID: 122062 Comm: kworker/u16:16 Kdump: loaded Not tainted 7.1.0-rc4+ #ge05a759574b2 PREEMPT
Workqueue: nfsiod rpc_async_release
Call Trace:
<TASK>
dump_stack_lvl+0xaf/0x100
? nfs_write_completion+0x8f8/0xa50 [nfs]
print_report+0x157/0x4a1
? __virt_addr_valid+0x1fb/0x400
? nfs_write_completion+0x8f8/0xa50 [nfs]
kasan_report+0xc2/0x190
? nfs_write_completion+0x8f8/0xa50 [nfs]
nfs_write_completion+0x8f8/0xa50 [nfs]
? nfs_commit_release_pages+0xbd0/0xbd0 [nfs]
? lock_acquire+0x182/0x2e0
? process_one_work+0x937/0x1890
? nfs_pgio_header_alloc+0xd0/0xd0 [nfs]
rpc_free_task+0xee/0x160
rpc_async_release+0x5d/0xb0
process_one_work+0x9b0/0x1890
? pwq_dec_nr_in_flight+0xed0/0xed0
? rpc_final_put_task+0x140/0x140
worker_thread+0x75a/0x10a0
? process_one_work+0x1890/0x1890
? kthread+0x1af/0x4d0
? process_one_work+0x1890/0x1890
kthread+0x3d3/0x4d0
? kthread_affine_node+0x2c0/0x2c0
ret_from_fork+0x669/0xa50
? native_tss_update_io_bitmap+0x660/0x660
? __switch_to+0x9dd/0x1310
? kthread_affine_node+0x2c0/0x2c0
ret_from_fork_asm+0x11/0x20
</TASK>
Allocated by task 121997 on cpu 3 at 31643.290294s:
kasan_save_stack+0x1e/0x40
kasan_save_track+0x13/0x60
__kasan_slab_alloc+0x62/0x70
kmem_cache_alloc_noprof+0x1ab/0x4e0
nfs_page_create+0x152/0x460 [nfs]
nfs_page_create_from_folio+0x7e/0x210 [nfs]
nfs_update_folio+0x7a9/0x32a0 [nfs]
nfs_write_end+0x290/0xc60 [nfs]
generic_perform_write+0x4ce/0x990
nfs_file_write+0x6b3/0xce0 [nfs]
vfs_write+0x63c/0xfa0
ksys_write+0x122/0x240
do_syscall_64+0xc3/0x13f0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Freed by task 122046 on cpu 0 at 31647.037964s:
kasan_save_stack+0x1e/0x40
kasan_save_track+0x13/0x60
kasan_save_free_info+0x37/0x60
__kasan_slab_free+0x3b/0x60
kmem_cache_free+0x11b/0x5a0
nfs_page_group_destroy+0x13a/0x210 [nfs]
nfs_unlock_and_release_request+0x64/0x90 [nfs]
nfs_commit_release_pages+0x339/0xbd0 [nfs]
nfs_commit_release+0x51/0xb0 [nfs]
rpc_free_task+0xee/0x160
rpc_async_release+0x5d/0xb0
process_one_work+0x9b0/0x1890
worker_thread+0x75a/0x10a0
kthread+0x3d3/0x4d0
ret_from_fork+0x669/0xa50
ret_from_fork_asm+0x11/0x20
The buggy address belongs to the object at ffff888118af2040\x0a which belongs to the cache nfs_page of size 96
The buggy address is located 24 bytes inside of\x0a freed 96-byte region [ffff888118af2040, ffff888118af20a0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x118af2
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x4000000000000040(head|zone=2)
page_type: f5(slab)
raw: 4000000000000040 ffff88818cf2c4c0 ffffea000e61b990 ffffea0004e7d110
raw: 0000000000000000 0000000800190019 00000000f5000000 0000000000000000
head: 4000000000000040 ffff88818cf2c4c0 ffffea000e61b990 ffffea0004e7d110
head: 0000000000000000 0000000800190019 00000000f5000000 0000000000000000
head: 4000000000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 121997, tgid 121997 (rsync), ts 31643290274577, free_ts 31642154777182
post_alloc_hook+0xd1/0x100
get_page_from_freelist+0xbad/0x2910
__alloc_frozen_pages_noprof+0x1c6/0x4a0
allocate_slab+0x330/0x620
___slab_alloc+0xe9/0x930
kmem_cache_alloc_noprof+0x35b/0x4e0
nfs_page_create+0x152/0x460 [nfs]
nfs_page_create_from_folio+0x7e/0x210 [nfs]
nfs_update_folio+0x7a9/0x32a0 [nfs]
nfs_write_end+0x290/0xc60 [nfs]
generic_perform_write+0x4ce/0x990
nfs_file_write+0x6b3/0xce0 [nfs]
vfs_write+0x63c/0xfa0
ksys_write+0x122/0x240
do_syscall_64+0xc3/0x13f0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
page last free pid 122202 tgid 122202 stack trace:
__free_frozen_pages+0x6da/0xf30
qlist_free_all+0x53/0x130
kasan_quarantine_reduce+0x198/0x1f0
__kasan_slab_alloc+0x46/0x70
kmem_cache_alloc_noprof+0x1ab/0x4e0
__alloc_object+0x2f/0x230
__create_object+0x22/0x80
kmem_cache_alloc_node_noprof+0x416/0x4d0
__alloc_skb+0x146/0x6e0
tcp_stream_alloc_skb+0x35/0x660
tcp_sendmsg_locked+0x1746/0x4260
tcp_sendmsg+0x2f/0x40
inet_sendmsg+0x9e/0xe0
__sock_sendmsg+0xd9/0x180
sock_sendmsg+0x122/0x200
xprt_sock_sendmsg+0x4ff/0x9a0
Memory state around the buggy address:
ffff888118af1f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc
ffff888118af1f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888118af2000: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
^
ffff888118af2080: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
ffff888118af2100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Reviewed-by Jeff Layton <jlayton@kernel.org>
Fixes: 5d3869a41f ("NFS: fix writeback in presence of errors")
Cc: Olga Kornievskaia <okorniev@redhat.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: linux-nfs@vger.kernel.org
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Commit a5242d37c8 ("erofs: error out obviously illegal extents in
advance") changed the per-extent algorithm presence check from "is the
bit set" to "is the only bit set":
- !(sbi->available_compr_algs & (1 << map->m_algorithmformat))
+ (sbi->available_compr_algs ^ BIT(map->m_algorithmformat))
`available_compr_algs` is a bitmap of every compression algorithm
available in the image (z_erofs_parse_cfgs() iterates it with
for_each_set_bit()), so an image that enables more than one algorithm
has multiple bits set. XOR is zero only when the bitmap is exactly
BIT(map->m_algorithmformat); for any image with two or more algorithms
the test is non-zero for every extent and the read fails with
-EFSCORRUPTED ("inconsistent algorithmtype %u").
Reproducer (mkfs.erofs from erofs-utils 1.7.1):
$ mkdir src
$ yes A | head -c 100K > src/a
$ head -c 64K /dev/zero > src/b
$ mkfs.erofs -zlz4:deflate multi.erofs src
$ mount -t erofs -o loop multi.erofs /mnt
$ cat /mnt/a >/dev/null
cat: /mnt/a: Structure needs cleaning
$ dmesg | tail
erofs (device loop0): inconsistent algorithmtype 0 for nid 46
erofs (device loop0): read error -117 @ 0 of nid 46
The erofs on-disk format (Z_EROFS_COMPRESSION_MAX = 4 with LZ4, LZMA,
DEFLATE, ZSTD) and the kernel parser explicitly support
multi-algorithm images, and erofs-utils 1.7.1 generates them via the
"-z X:Y" syntax.
Restore the original per-bit presence check.
Fixes: a5242d37c8 ("erofs: error out obviously illegal extents in advance")
Signed-off-by: Zhan Xusheng <zhanxusheng@xiaomi.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
A deferred byte-range lock (an SMB2_LOCK that blocks) registers an async work on
conn->async_requests via setup_async_work(), with cancel_fn =
smb2_remove_blocked_lock and cancel_argv[0] pointing at the struct file_lock.
When the request is cancelled, the worker frees the file_lock with
locks_free_lock() and takes the cancelled early-exit, which "goto out"s and never
reaches release_async_work() -- the only site that unlinks the work from
conn->async_requests and clears cancel_fn/cancel_argv. The work therefore stays
matchable on async_requests with a live cancel_fn pointing at the freed file_lock,
until connection teardown finally runs release_async_work().
smb2_cancel() fires cancel_fn unconditionally with no state guard, so a second
SMB2_CANCEL for the same AsyncId, arriving in that window, re-runs
smb2_remove_blocked_lock() on the freed file_lock -- a slab use-after-free:
BUG: KASAN: slab-use-after-free in __locks_delete_block
__locks_delete_block
locks_delete_block
ksmbd_vfs_posix_lock_unblock
smb2_remove_blocked_lock
smb2_cancel <- 2nd SMB2_CANCEL fires cancel_fn
handle_ksmbd_work
Allocated by ...: locks_alloc_lock <- smb2_lock
Freed by ...: locks_free_lock <- smb2_lock (cancelled branch)
... cache file_lock_cache of size 192
Reproduced on mainline with KASAN by an authenticated SMB client.
Skip a work whose state is already KSMBD_WORK_CANCELLED so its cancel callback
cannot be fired a second time.
Cc: stable@vger.kernel.org
Signed-off-by: Gil Portnoy <dddhkts1@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Two concurrent same-user DHnC reconnects can both observe fp->conn == NULL
before either sets it. ksmbd_reopen_durable_fd() checks fp->conn to guard
against a handle already being reconnected, but the check and the binding
assignment are not atomic: both threads pass the guard, both call
ksmbd_conn_get() on the same fp, and both eventually reach
kfree(fp->owner.name) -- a double-free of the owner.name slab object.
The double-bound ksmbd_file also causes a write-UAF on the 344-byte
ksmbd_file_cache object when a concurrent smb2_close() spins on fp->f_lock
after the object has been freed by the losing reconnect path.
KASAN on 7.1-rc5 (48-thread concurrent reconnect, 3000 cycles):
BUG: KASAN: double-free in ksmbd_reopen_durable_fd+0x268/0x308
BUG: KASAN: slab-use-after-free in _raw_spin_lock+0xac/0x150
Write of size 4 at offset 24 into freed ksmbd_file_cache object
Five double-bind windows observed; 63 total KASAN reports triggered.
Fix: validate and claim fp->conn under write_lock(&global_ft.lock) so the
check-and-claim is atomic. ksmbd_lookup_durable_fd() already treats
fp->conn != NULL as "in use" and skips such an fp; setting fp->conn before
dropping the lock closes the race. ksmbd_conn_get() is a non-sleeping
refcount increment, safe under the rwlock. The rollback path on __open_id()
failure also clears fp->conn/tcon under the lock so concurrent readers see
a consistent state.
Fixes: b1f1e80620 ("ksmbd: centralize ksmbd_conn final release to plug transport leak")
Assisted-by: Henry (Claude):claude-opus-4
Signed-off-by: Gil Portnoy <dddhkts1@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb2_oplock_break_noti() and smb2_lease_break_noti() read opinfo->conn
into a local with neither READ_ONCE() nor a NULL check. Both run from
oplock_break() after opinfo_get_list() has dropped ci->m_lock, so a
concurrent SMB2 LOGOFF (session_fd_check()) can set op->conn = NULL
under ci->m_lock within that window. ksmbd_conn_r_count_inc(conn) then
writes through NULL at offset 0xc4 -- a remotely triggerable oops.
Guard both reads the way compare_guid_key() already does: read
opinfo->conn with READ_ONCE() and return early if it is NULL, before
allocating the work struct so nothing leaks. A NULL conn means the
client is gone and the break is moot, so return 0; oplock_break() treats
that as success and runs the normal teardown.
Fixes: c8efcc7861 ("ksmbd: add support for durable handles v1/v2")
Assisted-by: Henry (Claude):claude-opus-4
Signed-off-by: Gil Portnoy <dddhkts1@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull smb client fixes from Steve French:
- fix uninitialized variable in smb2_writev_callback()
- detect short folioq copy in cifs_copy_folioq_to_iter()
* tag 'v7.1-rc6-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb: client: fix uninitialized variable in smb2_writev_callback
smb: client: detect short folioq copy in cifs_copy_folioq_to_iter()
Update a comment to refer to folios instead of pages.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xfs_mountfs currently ignores all errors from xfs_fs_reserve_ag_blocks,
which can lead to the mount path continuing on corruption errors.
Fix the check to only ignore -ENOSPC as in other callers, and unwind for
all other errors.
Fixes: 81ed94751b ("xfs: fix log intent recovery ENOSPC shutdowns when inactivating inodes")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Keep the rtgroup reference until after reporting the write pointer, as
that uses it. Right now this is not a major issue as we don't support
shrinking file systems in a way that makes RTGs go away, but let's stick
to the proper reference counting to prepare for that.
Fixes: c6ce65cb17 ("xfs: add write pointer to xfs_rtgroup_geometry")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xrep_cow_find_bad_rt() initializes scrub rtgroup state before the
force-rebuild path calls xrep_cow_mark_file_range(). If that call
fails, the code jumps directly to out_rtg, which skips the scrub
rtgroup cleanup and only drops the local rtgroup reference.
Remove the unnecessary jump so the function falls through to out_sr,
ensuring the realtime cursors, lock state, and sr->rtg reference are
released before returning.
Fixes: fd97fe1112 ("xfs: fix CoW forks for realtime files")
Cc: <stable@vger.kernel.org> # v6.14
Signed-off-by: Yingjie Gao <gaoyingjie@uniontech.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xrep_cow_find_bad() returns success after the cleanup labels even if
AG setup, btree queries, or bitmap updates failed. This can make
repair continue with an incomplete bad-file-offset bitmap instead of
stopping at the original error.
The force-rebuild path has a related cleanup problem. If
xrep_cow_mark_file_range() fails, the function returns directly and
skips the scrub AG context and perag cleanup.
Let the force-rebuild path fall through to the existing cleanup code
and return the saved error after cleanup.
Fixes: dbbdbd0086 ("xfs: repair problems in CoW forks")
Cc: <stable@vger.kernel.org> # v6.8
Signed-off-by: Yingjie Gao <gaoyingjie@uniontech.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xfs_fs_map_blocks() currently passes XFS_BMAPI_ENTIRE to xfs_bmapi_read(),
which causes the bmap code to expand the mapping to cover the entire
extent rather than the requested range.
A single LAYOUTGET request from the client can cause the server to
issue multiple calls to xfs_fs_map_blocks() for different offsets
within the same extent. Because the use of XFS_BMAPI_ENTIRE flag,
these calls can produce overlapping mappings.
As a result, the LAYOUTGET reply sent to the NFS client may contain
overlapping extents. This creates ambiguity in extent selection for a
given file range, which can lead to incorrect device selection,
inconsistent handling of datastate, and ultimately data corruption or
protocol violations on the client side.
Problem discovered with xfstest generic/075 test using NFSv4.2 mount
with SCSI layout.
Fix this by replacing the XFS_BMAPI_ENTIRE flag with '0' so that
xfs_bmapi_read() returns only the mapping for the requested range.
Fixes: cc6c40e09d ("NFSD/blocklayout: Support multiple extents per LAYOUTGET").
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xfs_fs_map_blocks() acquires the data map lock and then calls
xfs_bmapi_read(). If xfs_bmapi_read() fails, the function currently
still falls through to xfs_bmbt_to_iomap(), which consumes an
uninitialized imap record and may return invalid data to the caller.
Fix this by releasing the data map lock and returning immediately when
xfs_bmapi_read() reports an error. This prevents xfs_bmbt_to_iomap()
from being called with an uninitialized xfs_bmbt_irec.
Fixes: 527851124d ("xfs: implement pNFS export operations")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Under heavy garbage collection pressure from RocksDB workloads,
filesystem shutdowns can occur in xfs_zone_gc_iter_irec when
xfs_iget() returns -EINVAL for deleted files.
Fix this by handling -EINVAL just like we handle -ENOENT, allowing
zone GC to safely ignore stale mappings.
Fixes: 080d01c41d ("xfs: implement zoned garbage collection")
Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Pull smb server fixes from Steve French:
- security fix for FSCTL_SET_SPARSE
- fix leak in ksmbd_query_inode_status()
- fix OOB read in smb_check_perm_dacl()
* tag 'v7.1-rc6-ksmbd-server-fixes' of git://git.samba.org/ksmbd:
ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE
ksmbd: release ksmbd_inode ref via ksmbd_inode_put on lookup paths
ksmbd: OOB read regression in smb_check_perm_dacl() ACE-walk loops
z_erofs_decompress_kickoff() can race with filesystem unmount, causing
a use-after-free on sbi->sync_decompress.
When I/O completes, z_erofs_endio() calls z_erofs_decompress_kickoff()
to queue z_erofs_decompressqueue_work() asynchronously. Then, after all
folios are unlocked, unmount workflow can proceed and sbi will be freed
before accessing to sbi->sync_decompress.
Thread (unmount) I/O completion kworker
queue_work
z_erofs_decompressqueue_work
(all folios are unlocked)
cleanup_mnt
..
erofs_kill_sb
erofs_sb_free
kfree(sbi)
access sbi->sync_decompress // UAF!!
Fixes: 40452ffca3 ("erofs: add sysfs node to control sync decompression strategy")
Reported-by: syzbot+52bae5c495dbe261a0bc@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=52bae5c495dbe261a0bc
Reviewed-by: Chao Yu <chao@kernel.org>
Reviewed-by: Jianan Huang <jnhuang95@gmail.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
The conversion to qnx6_get_folio() in commit b2aa61556f
("qnx6: Convert qnx6_get_page() to qnx6_get_folio()")
introduced a regression in directory iteration. The pointer 'de'
and the 'limit' address were calculated using byte offsets from
a char pointer without scaling by the size of a QNX6 directory
entry.
This causes the driver to read from incorrect memory offsets,
leading to "invalid direntry size" errors and premature
termination of directory scans.
Fix this by casting 'kaddr' to 'struct qnx6_dir_entry *' before
applying the offset and last_entry(...) increments. This allows the
compiler to correctly scale the pointer arithmetic by the 32-byte
stride of the directory entry structure.
Fixes: b2aa61556f ("qnx6: Convert qnx6_get_page() to qnx6_get_folio()")
Cc: stable@vger.kernel.org
Signed-off-by: Arpith Kalaginanavoor <arpithk@nvidia.com>
Link: https://patch.msgid.link/20260526123858.1683035-1-arpithk@nvidia.com
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
atomic_create() in fs/namei.c drops the reference to the dentry
when it returns an error.
This behaviour was imported into dentry_create() so that it
will drop the reference if an error is returned from atomic_create(),
though not if vfs_create() returns an error (in the case where
->atomic_create is not supported).
The caller - nfsd4_create_file() - is made aware of this by checking
path->dentry, which will either be a counted reference to a dentry, or
an error pointer.
However the change to use start_creating()/end_creating() (which landed
shortly before the dentry_create() change landed, though was likely
developed around the same time) means that nfsd4_create_file() *needs* a
valid dentry so that it can unlock the parent.
The net result is that if NFSD exports a filesystem which uses
->atomic_create, and if a call to ->atomic_create returns an error, then
nfsd4_create_file() will pass an error pointer to end_creating()
and the parent will not be unlocked.
Fix this by changing dentry_create() to make sure path->dentry is always
a valid dentry, never an error-pointer. The actual error is already
returned a different way.
Note that if ->atomic_create() returns a different dentry (which may not
be possible in practice) we are guaranteed (because it is only ever
provided by d_spliace_alias()) that it will have the same d_parent and
so it will have the same effect when passed to end_creating().
Fixes: 64a989dbd1 ("VFS/knfsd: Teach dentry_create() to use atomic_open()")
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/177969022571.3379282.16448744624428323496@noble.neil.brown.name
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@hammerspace.com>
Reviewed-by: Jori Koolstra <jkoolstra@xs4all.nl>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
cifs_copy_folioq_to_iter() copies a requested number of bytes from
a folio queue into the destination iterator. Since the encrypted
SMB2 READ path was changed to pass the server-declared payload
length (data_len) instead of the larger folioq buffer length, the
caller can ask for fewer bytes than the folio queue holds.
In that case the helper continues walking the remaining folios after
data_size has reached zero and calls copy_folio_to_iter() with
len = 0, which is unnecessary work.
The helper also returns 0 (success) when the folio queue is
exhausted before data_size bytes have been copied. The caller has
no way to distinguish that from a full copy and the reported
transfer count ends up larger than the amount of data placed in the
iterator.
Add an early exit when data_size reaches zero, and return an error
when the folio queue is exhausted before all requested bytes have
been copied.
Signed-off-by: Jeremy Erazo <mendozayt13@gmail.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
FSCTL_SET_SPARSE in fsctl_set_sparse() modifies the file's sparse
attribute and saves it through xattr without any permission checks.
This exposes two issues:
1) A client on a read-only share can change the sparse attribute
on files it opened, even though the share is read-only.
Other FSCTL write operations already check
test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE),
but FSCTL_SET_SPARSE does not.
2) Even on writable shares, clients without FILE_WRITE_DATA or
FILE_WRITE_ATTRIBUTES access should not modify the sparse
attribute. Similar handle-level checks exist in other functions
but are missing here.
Add both share-level writable check and per-handle access check.
Use goto out on error to avoid leaking file references.
Fixes: e2f34481b2 ("cifsd: add server-side procedures for SMB3")
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steve French <smfrench@gmail.com>
Signed-off-by: Sean Shen <grayhat@foxmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
ksmbd_query_inode_status() and ksmbd_lookup_fd_inode() both take a
reference on a ksmbd_inode via __ksmbd_inode_lookup() (which performs
atomic_inc_not_zero()) and later release it using a bare
atomic_dec(&ci->m_count). Unlike ksmbd_inode_put(), a bare
atomic_dec() does not check whether the reference count has reached
zero, so if the caller happens to drop the last reference, the
ksmbd_inode is leaked: it stays in the global inode hash table with
m_count == 0, future __ksmbd_inode_lookup() calls reject it via
atomic_inc_not_zero(), and ksmbd_inode_free() is never invoked.
The race is:
T1: __ksmbd_inode_lookup() -> atomic_inc_not_zero(): m_count = 2
T2: ksmbd_inode_put() -> atomic_dec_and_test(): m_count = 1
(not freed)
T1: atomic_dec(&ci->m_count) -> m_count = 0
return (LEAK)
In ksmbd_lookup_fd_inode() the matched-fp path (which now also uses
ksmbd_inode_put()) cannot currently reach m_count == 0 because the
matched ksmbd_file holds its own reference on ci, but converting it to
the proper API keeps the three call sites consistent and avoids
future regressions if the locking changes.
Because ksmbd_inode_put() may free the ksmbd_inode if this drops the
last reference, the call must happen after up_read(&ci->m_lock) on the
two affected paths in ksmbd_lookup_fd_inode(). On the no-match path
this is a pure reordering; on the matched path ksmbd_fp_get() is
moved above the unlock so that the returned ksmbd_file is pinned
before the inode reference is released.
Signed-off-by: Aleksandr Golovnya <cofedish@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Commit d07b26f392 ("ksmbd: require minimum ACE size in
smb_check_perm_dacl()") introduced a transposed bounds check:
if (offsetof(struct smb_ace, sid) + aces_size < CIFS_SID_BASE_SIZE)
Since offsetof(..sid) is 8 and CIFS_SID_BASE_SIZE is 8, this evaluates
to `aces_size < 0`. Because `aces_size` is always non-negative, this
check becomes dead code and never breaks the loop.
Worse, that commit removed the old 4-byte guard, meaning the loop now
reads `ace->size` (offset 2) even when `aces_size` is 0-3 bytes. This
re-opens a 2-byte heap out-of-bounds (OOB) read past the pntsd allocation
during subsequent SMB2_CREATE operations.
Fix this by properly transposing the comparison to require at least
16 bytes (8-byte offset + 8-byte SID base), matching the correct form
used in smb_inherit_dacl().
Fixes: d07b26f392 ("ksmbd: require minimum ACE size in smb_check_perm_dacl()")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ganiyev <ali.qaniyev@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull nfsd fixes from Chuck Lever:
"Regressions:
- Tighten bounds checking for sunrpc cache hash tables
- Don't report key material in the ftrace log
Stable fix:
- Fix lockd's implementation of the NLM TEST procedure"
* tag 'nfsd-7.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
lockd: fix TEST handling when not all permissions are available.
NFSD: Report whether fh_key was actually updated
sunrpc: prevent out-of-bounds read in __cache_seq_start()
Pull misc fixes from Andrew Morton:
"13 hotfixes. 9 are for MM. 9 are cc:stable and the remaining 4 address
post-7.1 issues or aren't considered suitable for backporting.
All patches are singletons - please see the individual changelogs for
details"
* tag 'mm-hotfixes-stable-2026-05-25-16-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
Revert "mm: introduce a new page type for page pool in page type"
mm/vmalloc: do not trigger BUG() on BH disabled context
MAINTAINERS, mailmap: change email for Eugen Hristev
mm/migrate_device: fix pgtable leak in migrate_vma_insert_huge_pmd_page
kernel/fork: validate exit_signal in kernel_clone()
mm: memcontrol: propagate NMI slab stats to memcg vmstats
mm/damon/sysfs-schemes: delete tried region in regions_rmdirs()
mm/rmap: initialize nr_pages to 1 at loop start in try_to_unmap_one
zram: fix use-after-free in zram_writeback_endio
memfd: deny writeable mappings when implying SEAL_WRITE
ipc: limit next_id allocation to the valid ID range
Revert "mm/hugetlbfs: update hugetlbfs to use mmap_prepare"
MAINTAINERS: .mailmap: update after GEHC spin-off
Pull smb server fixes from Steve French:
- fix for creating tmpfiles
- fix durable reconnect error path
- validate SID in security descriptor when inheriting DACL
* tag 'v7.1-rc5-ksmbd-server-fixes' of git://git.samba.org/ksmbd:
smb/server: promote S_DEL_ON_CLS to S_DEL_PENDING when close
ksmbd: validate SID in parent security descriptor during ACL inheritance
ksmbd: fix durable reconnect error path file lifetime
Pull btrfs fixes from David Sterba:
"A batch of fixes to simple quotas:
- add conditional rescheduling point not dependent on the lock during
inode iterations to avoid delays with PREEMPT_NONE enabled
- fix subvolume deletion so it does not break the squota invariants
- properly handle enabling squota, tracking extents in the initial
transaction
- catch and warn about underflows, clamp to zero to avoid further
problems
And one fix to inode size handling:
- fix handling of preallocated extents beyond i_size when not using
the no-holes feature"
* tag 'for-7.1-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: swallow btrfs_record_squota_delta() ENOENT
btrfs: clamp to avoid squota underflow
btrfs: fix squota accounting during enable generation
btrfs: check for subvolume before deleting squota qgroup
btrfs: always drop root->inodes lock before cond_resched()
btrfs: mark file extent range dirty after converting prealloc extents
Pull xfs fix from Carlos Maiolino:
"A single fix for a race in xfs buffer cache which may lead to
filesystem shutdown due to inconsistent metadata if the buffer
lookup happens to find an old dead buffer still in the cache"
* tag 'xfs-fixes-7.1-rc5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix a buffer lookup against removal race
Pull driver core fixes from Danilo Krummrich:
- Remove the software node on platform device release(); without this,
the software node remains registered after the device is gone and a
subsequent platform_device_register_full() reusing the same node
fails with -EBUSY
- In sysfs_update_group(), do not remove a pre-existing directory when
create_files() fails; the previous code would silently destroy a
sysfs group that the caller did not create
- Set fwnode->secondary to NULL in fwnode_init() to avoid dereferencing
uninitialized memory (e.g. in dev_to_swnode()) when the firmware node
is allocated on the stack or via a non-zeroing allocator
* tag 'driver-core-7.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
device property: set fwnode->secondary to NULL in fwnode_init()
sysfs: don't remove existing directory on update failure
driver core: platform: remove software node on release()
Pull smb client fixes from Steve French:
- Fix missing lock
- Fix dentry in use after unmounting
- cifs.upcall security fix
- require CAP_NET_ADMIN for swn netlink
- change allocation in DUP_CTX_STR to GFP_KERNEL
- minor smbdirect debug fix
- handle_read_data() folio fix
* tag 'v7.1-rc5-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb: client: change allocation requirements in DUP_CTX_STR macro
smb: client: require net admin for CIFS SWN netlink
smb: smbdirect: divide, not multiply, milliseconds by 1000
cifs: Fix busy dentry used after unmounting
smb: client: use data_len for SMB2 READ encrypted folioq copy
smb: client: reject userspace cifs.spnego descriptions
smb: client: protect tc_count increment in smb2_find_smb_sess_tcon_unlocked()
Pull zonefs fix from Damien Le Moal:
- Avoid potential overflow when converting a zonefs file number string
to an inode number (from Johannes)
* tag 'zonefs-7.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
zonefs: handle integer overflow in zonefs_fname_to_fno
The operations FUSE_NOTIFY_STORE and FUSE_NOTIFY_RETRIEVE allow the
FUSE daemon to actively write/read pagecache contents.
For directories with FOPEN_CACHE_DIR, the pagecache is used as
kernel-internal cache storage, and userspace is not supposed to have
direct access to this cache - in particular, fuse_parse_cache() will hit
WARN_ON() if the cache contains bogus data.
Reject FUSE_NOTIFY_STORE and FUSE_NOTIFY_RETRIEVE on anything other than
regular files with -EINVAL.
Fixes: 5d7bc7e868 ("fuse: allow using readdir cache")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Link: https://patch.msgid.link/20260519-fuse-dir-pagecache-v2-1-5428fa48e175@google.com
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
FUSE_NOTIFY_RETRIEVE must be limited to uptodate folios; !uptodate folios
can contain uninitialized data.
Since FUSE_NOTIFY_RETRIEVE is intended to only return data that is already
in the page cache and not wait for data from the FUSE daemon, treat
!uptodate folios as if they weren't present.
This only has security impact on systems that don't enable automatic
zero-initialization of all page allocations via
CONFIG_INIT_ON_ALLOC_DEFAULT_ON or init_on_alloc=1.
Cc: stable@kernel.org
Fixes: 2d45ba381a ("fuse: add retrieve request")
Signed-off-by: Jann Horn <jannh@google.com>
Link: https://patch.msgid.link/20260519-fuse-retrieve-uptodate-v1-1-a7a1912a37f9@google.com
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
This reverts commit ea52cb24cd ("mm/hugetlbfs: update hugetlbfs to use
mmap_prepare") with conflict resolution to account for changes in commit
ea52cb24cd ("mm/hugetlbfs: update hugetlbfs to use mmap_prepare").
The patch incorrectly handled hugetlb VMA lock allocation at the
mmap_prepare stage, where a failed allocation occurring after mmap_prepare
is called might result in the lock leaking.
There is no risk of a merge causing a similar issues, as
VMA_DONTEXPAND_BIT is set for hugetlb mappings.
As a first step in addressing this issue, simply revert the change so we
can rework how we do this having corrected the underlying issues.
We maintain the VMA flags changes as best we can, accounting for the fact
that we were working with a VMA descriptor previously and propagating
like-for-like changes for this.
Note that we invoke vma_set_flags() and do not call vma_start_write() as
vm_flags_set() does. This is OK as it's being done in an .mmap hook where
the VMA is not yet linked into the tree so nobody else can be accessing
it.
Link: https://lore.kernel.org/20260512160643.266960-1-ljs@kernel.org
Fixes: ea52cb24cd ("mm/hugetlbfs: update hugetlbfs to use mmap_prepare")
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
Reported-by: Mingyu Wang <25181214217@stu.xidian.edu.cn>
Closes: https://lore.kernel.org/linux-mm/20260425070700.562229-1-25181214217@stu.xidian.edu.cn/
Acked-by: Muchun Song <muchun.song@linux.dev>
Acked-by: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Introduce smb_validate_ntsd_sid() helper to safely validate Owner SID
and Group SID inside the NT Security Descriptor (smb_ntsd) retrieved
from the parent directory.
Cc: stable@vger.kernel.org
Signed-off-by: Junyi Liu <moss80199@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
After a durable reconnect succeeds, ksmbd_reopen_durable_fd() republishes
the same ksmbd_file into the session volatile-id table. If smb2_open()
then takes a later error path, cleanup first calls ksmbd_fd_put(work, fp)
and then unconditionally calls ksmbd_put_durable_fd(dh_info.fp).
In this case fp and dh_info.fp are the same object. The first put drops the
reconnect lookup reference, but the final durable put can run
__ksmbd_close_fd(NULL, fp). Because the final close is not session-aware,
it can free the file object without removing the volatile-id entry that was
just published into the session table.
Use the session-aware put for the final reconnect drop when the reconnect
had already succeeded and the error path is cleaning up the republished
file. Earlier reconnect failures, before fp is assigned to dh_info.fp, keep
using the durable-only put path.
Fixes: 1baff47b81 ("ksmbd: fix use-after-free in smb2_open during durable reconnect")
Signed-off-by: Junyi Liu <moss80199@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
The F_GETLK fcntl can work with either read access or write access or
both. It can query F_RDLCK and F_WRLCK locks in either case.
However lockd currently treats F_GETLK similar to F_SETLK in that read
access is required to query an F_RDLCK lock and write access is required
to query a F_WRLCK lock.
This is wrong and can cause problems - e.g. when qemu accesses a
read-only (e.g. iso) filesystem image over NFS (though why it queries
if it can get a write lock - I don't know. But it does, and this works
with local filesystems).
So we need TEST requests to be handled differently. To do this:
- change nlm_do_fopen() to accept O_RDWR as a mode and in that case
succeed if either a O_RDONLY or O_WRONLY file can be opened.
- change nlm_lookup_file() to accept a mode argument from caller,
instead of deducing base on lock time, and pass that on to nlm_do_fopen()
- change nlm4svc_retrieve_args() and nlmsvc_retrieve_args() to detect
TEST requests and pass O_RDWR as a mode to nlm_lookup_file, passing
the same mode as before for other requests. Also set
lock->fl.c.flc_file to whichever file is available for TEST requests.
- change nlmsvc_testlock() to also not calculate the mode, but to use
whatever was stored in lock->fl.c.flc_file.
This behaviour of lockd - requesting O_WRONLY access to TEST for
exclusive locks - has been present at least since git history began.
However it was hidden until recently because knfsd ignored the access
requested by lockd and required only READ access for all locking
requests (unless the underlying filesystem provided an f_op->open
function which checked access permissions).
The commit mentioned in Fixes: below changed nfsd_permission() to NOT
override the access request for LOCK requests and this exposed the bug
that we are now fixing.
Note that there is another issue that this patch does not address.
The flock(.., LOCK_EX) call is permitted on a read-only file descriptor.
Linux NFS maps this to NLM locking as whole-file byte-range locks.
nfsd will see this as though it were fcntl( F_SETLK (F_WRLCK)) and will
now require write access, which it might not be able to get.
It is not clear if this is a problem in practice, or what the best
solution might be. So no attempt is made to address it.
Reported-by: Tj <tj.iam.tj@proton.me>
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1128861
Fixes: 4cc9b9f2bf ("nfsd: refine and rename NFSD_MAY_LOCK")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The nfsd_ctl_fh_key_set tracepoint was introduced to capture
operator activity on the filehandle signing key. Earlier revisions
logged the key bytes verbatim; the version that landed hashes the
16 key bytes through crc32_le and stores the result.
CRC32 is a linear projection of its input rather than a one-way
function, and truncating any hash of fixed-size secret material
leaves the key recoverable under offline brute force when the
threat model includes an attacker with access to the trace ring.
The operational question the fingerprint was meant to answer is
whether a NFSD_CMD_THREADS_SET call that carries an
NFSD_A_SERVER_FH_KEY attribute actually replaced the active key or
re-installed the value already in place. Answer that question
directly: compare the incoming key bytes against the current
nn->fh_key inside nfsd_nl_fh_key_set() and surface a single bit to
the tracepoint. The event now prints "updated" when the stored
key changed and "unmodified" otherwise. A first set that fails
kmalloc reports "unmodified" because no key was installed.
Reported-by: jaeyeong <fin@spl.team>
Fixes: 62346217fd ("NFSD: Add a key for signing filehandles")
Cc: Benjamin Coddington <bcodding@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Currently, the macro DUP_CTX_STR allocates new_ctx->field using
GFP_ATOMIC. DUP_CTX_STR is only used in smb3_fs_context_dup(), which
is never called in an atomic context. Using GFP_ATOMIC puts unnecessary
pressure on emergency memory pools.
Change GFP_ATOMIC to GFP_KERNEL.
Signed-off-by: Fredric Cover <fredric.cover.lkernel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
