summaryrefslogtreecommitdiff
path: root/fs
AgeCommit message (Collapse)Author
2026-03-23xfs: only flush when COW fork blocks overlap data fork holesBrian Foster
The zero range hole mapping flush case has been lifted from iomap into XFS. Now that we have more mapping context available from the ->iomap_begin() handler, we can isolate the flush further to when we know a hole is fronted by COW blocks. Rather than purely rely on pagecache dirty state, explicitly check for the case where a range is a hole in both forks. Otherwise trim to the range where there does happen to be overlap and use that for the pagecache writeback check. This might prevent some spurious zeroing, but more importantly makes it easier to remove the flush entirely. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: look up cow fork extent earlier for buffered iomap_beginBrian Foster
To further isolate the need for flushing for zero range, we need to know whether a hole in the data fork is fronted by blocks in the COW fork or not. COW fork lookup currently occurs further down in the function, after the zero range case is handled. As a preparation step, lift the COW fork extent lookup to earlier in the function, at the same time as the data fork lookup. Only the lookup logic is lifted. The COW fork branch/reporting logic remains as is to avoid any observable behavior change from an iomap reporting perspective. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: flush eof folio before insert range size updateBrian Foster
The flush in xfs_buffered_write_iomap_begin() for zero range over a data fork hole fronted by COW fork prealloc is primarily designed to provide correct zeroing behavior in particular pagecache conditions. As it turns out, this also partially masks some odd behavior in insert range (via zero range via setattr). Insert range bumps i_size the length of the new range, flushes, unmaps pagecache and cancels COW prealloc, and then right shifts extents from the end of the file back to the target offset of the insert. Since the i_size update occurs before the pagecache flush, this creates a transient situation where writeback around EOF can behave differently. This appears to be corner case situation, but if happens to be fronted by COW fork speculative preallocation and a large, dirty folio that contains at least one full COW block beyond EOF, the writeback after i_size is bumped may remap that COW fork block into the data fork within EOF. The block is zeroed and then shifted back out to post-eof, but this is unexpected in that it leads to a written post-eof data fork block. This can cause a zero range warning on a subsequent size extension, because we should never find blocks that require physical zeroing beyond i_size. To avoid this quirk, flush the EOF folio before the i_size update during insert range. The entire range will be flushed, unmapped and invalidated anyways, so this should be relatively unnoticeable. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23iomap, xfs: lift zero range hole mapping flush into xfsBrian Foster
iomap zero range has a wart in that it also flushes dirty pagecache over hole mappings (rather than only unwritten mappings). This was included to accommodate a quirk in XFS where COW fork preallocation can exist over a hole in the data fork, and the associated range is reported as a hole. This is because the range actually is a hole, but XFS also has an optimization where if COW fork blocks exist for a range being written to, those blocks are used regardless of whether the data fork blocks are shared or not. For zeroing, COW fork blocks over a data fork hole are only relevant if the range is dirty in pagecache, otherwise the range is already considered zeroed. The easiest way to deal with this corner case is to flush the pagecache to trigger COW remapping into the data fork, and then operate on the updated on-disk state. The problem is that ext4 cannot accommodate a flush from this context due to being a transaction deadlock vector. Outside of the hole quirk, ext4 can avoid the flush for zero range by using the recently introduced folio batch lookup mechanism for unwritten mappings. Therefore, take the next logical step and lift the hole handling logic into the XFS iomap_begin handler. iomap will still flush on unwritten mappings without a folio batch, and XFS will flush and retry mapping lookups in the case where it would otherwise report a hole with dirty pagecache during a zero range. Note that this is intended to be a fairly straightforward lift and otherwise not change behavior. Now that the flush exists within XFS, follow on patches can further optimize it. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: flush dirty pagecache over hole in zoned mode zero rangeBrian Foster
For zoned filesystems a window exists between the first write to a sparse range (i.e. data fork hole) and writeback completion where we might spuriously observe holes in both the COW and data forks. This occurs because a buffered write populates the COW fork with delalloc, writeback submission removes the COW fork delalloc blocks and unlocks the inode, and then writeback completion remaps the physically allocated blocks into the data fork. If a zero range operation does a lookup during this window where both forks show a hole, it incorrectly reports a hole mapping for a range that contains data. This currently works because iomap checks for dirty pagecache over holes and unwritten mappings. If found, it flushes and retries the lookup. We plan to remove the hole flush logic from iomap, however, so lift the flush into xfs_zoned_buffered_write_iomap_begin() to preserve behavior and document the purpose for it. Zoned XFS filesystems don't support unwritten extents, so if zoned mode can come up with a way to close this transient hole window in the future, this flush can likely be removed. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: fix iomap hole map reporting for zoned zero rangeBrian Foster
The hole mapping logic for zero range in zoned mode is not quite correct. It currently reports a hole whenever one exists in the data fork. If the first write to a sparse range has completed and not yet written back, the blocks exist in the COW fork as delalloc until writeback completes, at which point they are allocated and mapped into the data fork. If a zero range occurs on a range that has not yet populated the data fork, we will incorrectly report it as a hole. Note that this currently functions correctly because we are bailed out by the pagecache flush in iomap_zero_range(). If a hole or unwritten mapping is reported with dirty pagecache, it assumes there is pending data, flushes to induce any pending block allocations/remaps, and retries the lookup. We want to remove this hack from iomap, however, so update iomap_begin() to only report a hole for zeroing when one exists in both forks. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: remove redundant validation in xlog_recover_attri_commit_pass2Long Li
Remove the redundant post-parse validation switch. By the time that block is reached, xfs_attri_validate() has already guaranteed all name lengths are non-zero via xfs_attri_validate_namelen(), and xfs_attri_validate_name_iovec() has already returned -EFSCORRUPTED for NULL names. For the REMOVE case, attr_value and value_len are structurally guaranteed to be NULL/zero because the parsing loop only populates them when value_len != 0. All checks in that switch are therefore dead code. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Long Li <leo.lilong@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: fix ri_total validation in xlog_recover_attri_commit_pass2Long Li
The ri_total checks for SET/REPLACE operations are hardcoded to 3, but xfs_attri_item_size() only emits a value iovec when value_len > 0, so ri_total is 2 when value_len == 0. For PPTR_SET/PPTR_REMOVE/PPTR_REPLACE, value_len is validated by xfs_attri_validate() to be exactly sizeof(struct xfs_parent_rec) and is never zero, so their hardcoded checks remain correct. This problem may cause log recovery failures. The following script can be used to reproduce the problem: #!/bin/bash mkfs.xfs -f /dev/sda mount /dev/sda /mnt/test/ touch /mnt/test/file for i in {1..200}; do attr -s "user.attr_$i" -V "value_$i" /mnt/test/file > /dev/null done echo 1 > /sys/fs/xfs/debug/larp echo 1 > /sys/fs/xfs/sda/errortag/larp attr -s "user.zero" -V "" /mnt/test/file echo 0 > /sys/fs/xfs/sda/errortag/larp umount /mnt/test mount /dev/sda /mnt/test/ # mount failed Fix this by deriving the expected count dynamically as "2 + !!value_len" for SET/REPLACE operations. Cc: stable@vger.kernel.org # v6.9 Fixes: ad206ae50eca ("xfs: check opcode and iovec count match in xlog_recover_attri_commit_pass2") Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Long Li <leo.lilong@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: close crash window in attr dabtree inactivationLong Li
When inactivating an inode with node-format extended attributes, xfs_attr3_node_inactive() invalidates all child leaf/node blocks via xfs_trans_binval(), but intentionally does not remove the corresponding entries from their parent node blocks. The implicit assumption is that xfs_attr_inactive() will truncate the entire attr fork to zero extents afterwards, so log recovery will never reach the root node and follow those stale pointers. However, if a log shutdown occurs after the leaf/node block cancellations commit but before the attr bmap truncation commits, this assumption breaks. Recovery replays the attr bmap intact (the inode still has attr fork extents), but suppresses replay of all cancelled leaf/node blocks, maybe leaving them as stale data on disk. On the next mount, xlog_recover_process_iunlinks() retries inactivation and attempts to read the root node via the attr bmap. If the root node was not replayed, reading the unreplayed root block triggers a metadata verification failure immediately; if it was replayed, following its child pointers to unreplayed child blocks triggers the same failure: XFS (pmem0): Metadata corruption detected at xfs_da3_node_read_verify+0x53/0x220, xfs_da3_node block 0x78 XFS (pmem0): Unmount and run xfs_repair XFS (pmem0): First 128 bytes of corrupted metadata buffer: 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ XFS (pmem0): metadata I/O error in "xfs_da_read_buf+0x104/0x190" at daddr 0x78 len 8 error 117 Fix this in two places: In xfs_attr3_node_inactive(), after calling xfs_trans_binval() on a child block, immediately remove the entry that references it from the parent node in the same transaction. This eliminates the window where the parent holds a pointer to a cancelled block. Once all children are removed, the now-empty root node is converted to a leaf block within the same transaction. This node-to-leaf conversion is necessary for crash safety. If the system shutdown after the empty node is written to the log but before the second-phase bmap truncation commits, log recovery will attempt to verify the root block on disk. xfs_da3_node_verify() does not permit a node block with count == 0; such a block will fail verification and trigger a metadata corruption shutdown. on the other hand, leaf blocks are allowed to have this transient state. In xfs_attr_inactive(), split the attr fork truncation into two explicit phases. First, truncate all extents beyond the root block (the child extents whose parent references have already been removed above). Second, invalidate the root block and truncate the attr bmap to zero in a single transaction. The two operations in the second phase must be atomic: as long as the attr bmap has any non-zero length, recovery can follow it to the root block, so the root block invalidation must commit together with the bmap-to-zero truncation. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Long Li <leo.lilong@huawei.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: factor out xfs_attr3_leaf_initLong Li
Factor out wrapper xfs_attr3_leaf_init function, which exported for external use. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Long Li <leo.lilong@huawei.com> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: factor out xfs_attr3_node_entry_removeLong Li
Factor out wrapper xfs_attr3_node_entry_remove function, which exported for external use. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Long Li <leo.lilong@huawei.com> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: only assert new size for datafork during truncate extentsLong Li
The assertion functions properly because we currently only truncate the attr to a zero size. Any other new size of the attr is not preempted. Make this assertion is specific to the datafork, preparing for subsequent patches to truncate the attribute to a non-zero size. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Long Li <leo.lilong@huawei.com> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23xfs: Use xarray to track SB UUIDs instead of plain array.Lukas Herbolt
Removing the plain array to track the UUIDs and switch to xarray makes it more readable. Signed-off-by: Lukas Herbolt <lukas@herbolt.com> [cem: remove unneeded return from xfs_uuid_unmount] Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-23fanotify: replace deprecated strcpy in fanotify_info_copy_{name,name2}Thorsten Blum
strcpy() has been deprecated [1] because it performs no bounds checking on the destination buffer, which can lead to buffer overflows. Replace it with the safer strscpy(). Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1] Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Link: https://patch.msgid.link/20260321210544.519259-4-thorsten.blum@linux.dev Signed-off-by: Jan Kara <jack@suse.cz>
2026-03-22ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len()Namjae Jeon
After this commit (e2b76ab8b5c9 "ksmbd: add support for read compound"), response buffer management was changed to use dynamic iov array. In the new design, smb2_calc_max_out_buf_len() expects the second argument (hdr2_len) to be the offset of ->Buffer field in the response structure, not a hardcoded magic number. Fix the remaining call sites to use the correct offsetof() value. Cc: stable@vger.kernel.org Fixes: e2b76ab8b5c9 ("ksmbd: add support for read compound") Signed-off-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2026-03-22ksmbd: fix memory leaks and NULL deref in smb2_lock()Werner Kasselman
smb2_lock() has three error handling issues after list_del() detaches smb_lock from lock_list at no_check_cl: 1) If vfs_lock_file() returns an unexpected error in the non-UNLOCK path, goto out leaks smb_lock and its flock because the out: handler only iterates lock_list and rollback_list, neither of which contains the detached smb_lock. 2) If vfs_lock_file() returns -ENOENT in the UNLOCK path, goto out leaks smb_lock and flock for the same reason. The error code returned to the dispatcher is also stale. 3) In the rollback path, smb_flock_init() can return NULL on allocation failure. The result is dereferenced unconditionally, causing a kernel NULL pointer dereference. Add a NULL check to prevent the crash and clean up the bookkeeping; the VFS lock itself cannot be rolled back without the allocation and will be released at file or connection teardown. Fix cases 1 and 2 by hoisting the locks_free_lock()/kfree() to before the if(!rc) check in the UNLOCK branch so all exit paths share one free site, and by freeing smb_lock and flock before goto out in the non-UNLOCK branch. Propagate the correct error code in both cases. Fix case 3 by wrapping the VFS unlock in an if(rlock) guard and adding a NULL check for locks_free_lock(rlock) in the shared cleanup. Found via call-graph analysis using sqry. Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Cc: stable@vger.kernel.org Suggested-by: ChenXiaoSong <chenxiaosong@kylinos.cn> Signed-off-by: Werner Kasselman <werner@verivus.com> Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn> Acked-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2026-03-22ksmbd: fix use-after-free and NULL deref in smb_grant_oplock()Werner Kasselman
smb_grant_oplock() has two issues in the oplock publication sequence: 1) opinfo is linked into ci->m_op_list (via opinfo_add) before add_lease_global_list() is called. If add_lease_global_list() fails (kmalloc returns NULL), the error path frees the opinfo via __free_opinfo() while it is still linked in ci->m_op_list. Concurrent m_op_list readers (opinfo_get_list, or direct iteration in smb_break_all_levII_oplock) dereference the freed node. 2) opinfo->o_fp is assigned after add_lease_global_list() publishes the opinfo on the global lease list. A concurrent find_same_lease_key() can walk the lease list and dereference opinfo->o_fp->f_ci while o_fp is still NULL. Fix by restructuring the publication sequence to eliminate post-publish failure: - Set opinfo->o_fp before any list publication (fixes NULL deref). - Preallocate lease_table via alloc_lease_table() before opinfo_add() so add_lease_global_list() becomes infallible after publication. - Keep the original m_op_list publication order (opinfo_add before lease list) so concurrent opens via same_client_has_lease() and opinfo_get_list() still see the in-flight grant. - Use opinfo_put() instead of __free_opinfo() on err_out so that the RCU-deferred free path is used. This also requires splitting add_lease_global_list() to take a preallocated lease_table and changing its return type from int to void, since it can no longer fail. Fixes: 1dfd062caa16 ("ksmbd: fix use-after-free by using call_rcu() for oplock_info") Cc: stable@vger.kernel.org Signed-off-by: Werner Kasselman <werner@verivus.com> Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn> Acked-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2026-03-22ksmbd: do not expire session on binding failureHyunwoo Kim
When a multichannel session binding request fails (e.g. wrong password), the error path unconditionally sets sess->state = SMB2_SESSION_EXPIRED. However, during binding, sess points to the target session looked up via ksmbd_session_lookup_slowpath() -- which belongs to another connection's user. This allows a remote attacker to invalidate any active session by simply sending a binding request with a wrong password (DoS). Fix this by skipping session expiration when the failed request was a binding attempt, since the session does not belong to the current connection. The reference taken by ksmbd_session_lookup_slowpath() is still correctly released via ksmbd_user_session_put(). Cc: stable@vger.kernel.org Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Acked-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2026-03-22Merge tag 'v7.0-rc5' into driver-core-nextDanilo Krummrich
We need the driver-core fixes in here as well to build on top of. Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-03-21Merge tag 'for-7.0-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "Another batch of fixes for problems that have been identified by tools analyzing code or by fuzzing. Most of them are short, two patches fix the same thing in many places so the diffs are bigger. - handle potential NULL pointer errors after attempting to read extent and checksum trees - prevent ENOSPC when creating many qgroups by ioctls in the same transaction - encoded write ioctl fixes (with 64K page and 4K block size): - fix unexpected bio length - do not let compressed bios and pages interfere with page cache - compression fixes on setups with 64K page and 4K block size: fix folio length assertions (zstd and lzo) - remap tree fixes: - make sure to hold block group reference while moving it - handle early exit when moving block group to unused list - handle deleted subvolumes with inconsistent state of deletion progress" * tag 'for-7.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: reject root items with drop_progress and zero drop_level btrfs: check block group before marking it unused in balance_remap_chunks() btrfs: hold block group reference during entire move_existing_remap() btrfs: fix an incorrect ASSERT() condition inside lzo_decompress_bio() btrfs: fix an incorrect ASSERT() condition inside zstd_decompress_bio() btrfs: do not touch page cache for encoded writes btrfs: fix a bug that makes encoded write bio larger than expected btrfs: reserve enough transaction items for qgroup ioctls btrfs: check for NULL root after calls to btrfs_csum_root() btrfs: check for NULL root after calls to btrfs_extent_root()
2026-03-20Merge tag 'execve-v7.0-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull execve fixes from Kees Cook: - binfmt_elf_fdpic: fix AUXV size calculation (Andrei Vagin) - fs/tests: exec: Remove bad test vector * tag 'execve-v7.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: fs/tests: exec: Remove bad test vector binfmt_elf_fdpic: fix AUXV size calculation for ELF_HWCAP3 and ELF_HWCAP4
2026-03-20Merge tag 'v7.0-rc4-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull smb client fixes from Steve French: - Fix reporting of i_blocks - Fix Kerberos mounts with different usernames to same server - Trivial comment cleanup * tag 'v7.0-rc4-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6: smb: client: fix generic/694 due to wrong ->i_blocks cifs: smb1: fix comment typo smb: client: fix krb5 mount with username option
2026-03-20Merge tag 'v7.0-rc4-ksmbd-server-fixes' of git://git.samba.org/ksmbdLinus Torvalds
Pull smb server fixes from Steve French: - Three use after free fixes (in close, in compounded ops, and in tree disconnect) - Multichannel fix - return proper volume identifier (superblock uuid if available) in FS_OBJECT_ID queries * tag 'v7.0-rc4-ksmbd-server-fixes' of git://git.samba.org/ksmbd: ksmbd: fix use-after-free in durable v2 replay of active file handles ksmbd: fix use-after-free of share_conf in compound request ksmbd: use volume UUID in FS_OBJECT_ID_INFORMATION ksmbd: unset conn->binding on failed binding request ksmbd: fix share_conf UAF in tree_conn disconnect
2026-03-20writeback: don't block sync for filesystems with no data integrity guaranteesJoanne Koong
Add a SB_I_NO_DATA_INTEGRITY superblock flag for filesystems that cannot guarantee data persistence on sync (eg fuse). For superblocks with this flag set, sync kicks off writeback of dirty inodes but does not wait for the flusher threads to complete the writeback. This replaces the per-inode AS_NO_DATA_INTEGRITY mapping flag added in commit f9a49aa302a0 ("fs/writeback: skip AS_NO_DATA_INTEGRITY mappings in wait_sb_inodes()"). The flag belongs at the superblock level because data integrity is a filesystem-wide property, not a per-inode one. Having this flag at the superblock level also allows us to skip having to iterate every dirty inode in wait_sb_inodes() only to skip each inode individually. Prior to this commit, mappings with no data integrity guarantees skipped waiting on writeback completion but still waited on the flusher threads to finish initiating the writeback. Waiting on the flusher threads is unnecessary. This commit kicks off writeback but does not wait on the flusher threads. This change properly addresses a recent report [1] for a suspend-to-RAM hang seen on fuse-overlayfs that was caused by waiting on the flusher threads to finish: Workqueue: pm_fs_sync pm_fs_sync_work_fn Call Trace: <TASK> __schedule+0x457/0x1720 schedule+0x27/0xd0 wb_wait_for_completion+0x97/0xe0 sync_inodes_sb+0xf8/0x2e0 __iterate_supers+0xdc/0x160 ksys_sync+0x43/0xb0 pm_fs_sync_work_fn+0x17/0xa0 process_one_work+0x193/0x350 worker_thread+0x1a1/0x310 kthread+0xfc/0x240 ret_from_fork+0x243/0x280 ret_from_fork_asm+0x1a/0x30 </TASK> On fuse this is problematic because there are paths that may cause the flusher thread to block (eg if systemd freezes the user session cgroups first, which freezes the fuse daemon, before invoking the kernel suspend. The kernel suspend triggers ->write_node() which on fuse issues a synchronous setattr request, which cannot be processed since the daemon is frozen. Or if the daemon is buggy and cannot properly complete writeback, initiating writeback on a dirty folio already under writeback leads to writeback_get_folio() -> folio_prepare_writeback() -> unconditional wait on writeback to finish, which will cause a hang). This commit restores fuse to its prior behavior before tmp folios were removed, where sync was essentially a no-op. [1] https://lore.kernel.org/linux-fsdevel/CAJnrk1a-asuvfrbKXbEwwDSctvemF+6zfhdnuzO65Pt8HsFSRw@mail.gmail.com/T/#m632c4648e9cafc4239299887109ebd880ac6c5c1 Fixes: 0c58a97f919c ("fuse: remove tmp folio for writebacks and internal rb tree") Reported-by: John <therealgraysky@proton.me> Cc: stable@vger.kernel.org Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://patch.msgid.link/20260320005145.2483161-2-joannelkoong@gmail.com Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: David Hildenbrand (Arm) <david@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-19smb: client: fix generic/694 due to wrong ->i_blocksPaulo Alcantara
When updating ->i_size, make sure to always update ->i_blocks as well until we query new allocation size from the server. generic/694 was failing because smb3_simple_falloc() was missing the update of ->i_blocks after calling cifs_setsize(). So, fix this by updating ->i_blocks directly in cifs_setsize(), so all places that call it doesn't need to worry about updating ->i_blocks later. Reported-by: Shyam Prasad N <sprasad@microsoft.com> Closes: https://lore.kernel.org/r/CANT5p=rqgRwaADB=b_PhJkqXjtfq3SFv41SSTXSVEHnuh871pA@mail.gmail.com Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org> Cc: David Howells <dhowells@redhat.com> Cc: linux-cifs@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2026-03-19udf: fix partition descriptor append bookkeepingSeohyeon Maeng
Mounting a crafted UDF image with repeated partition descriptors can trigger a heap out-of-bounds write in part_descs_loc[]. handle_partition_descriptor() deduplicates entries by partition number, but appended slots never record partnum. As a result duplicate Partition Descriptors are appended repeatedly and num_part_descs keeps growing. Once the table is full, the growth path still sizes the allocation from partnum even though inserts are indexed by num_part_descs. If partnum is already aligned to PART_DESC_ALLOC_STEP, ALIGN(partnum, step) can keep the old capacity and the next append writes past the end of the table. Store partnum in the appended slot and size growth from the next append count so deduplication and capacity tracking follow the same model. Fixes: ee4af50ca94f ("udf: Fix mounting of Win7 created UDF filesystems") Cc: stable@vger.kernel.org Signed-off-by: Seohyeon Maeng <bioloidgp@gmail.com> Link: https://patch.msgid.link/20260310081652.21220-1-bioloidgp@gmail.com Signed-off-by: Jan Kara <jack@suse.cz>
2026-03-19netfs: Fix read abandonment during retryDavid Howells
Under certain circumstances, all the remaining subrequests from a read request will get abandoned during retry. The abandonment process expects the 'subreq' variable to be set to the place to start abandonment from, but it doesn't always have a useful value (it will be uninitialised on the first pass through the loop and it may point to a deleted subrequest on later passes). Fix the first jump to "abandon:" to set subreq to the start of the first subrequest expected to need retry (which, in this abandonment case, turned out unexpectedly to no longer have NEED_RETRY set). Also clear the subreq pointer after discarding superfluous retryable subrequests to cause an oops if we do try to access it. Fixes: ee4cdf7ba857 ("netfs: Speed up buffered reading") Signed-off-by: David Howells <dhowells@redhat.com> Link: https://patch.msgid.link/3775287.1773848338@warthog.procyon.org.uk Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org> cc: Paulo Alcantara <pc@manguebit.org> cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-19vfs: fix docstring of hash_name()Jori Koolstra
The docstring of hash_name() is falsely reporting that it returns the component length, whereas it returns a pointer to the terminating '/' or NUL character in the pathname being resolved. Signed-off-by: Jori Koolstra <jkoolstra@xs4all.nl> Link: https://patch.msgid.link/20260318203953.5770-1-jkoolstra@xs4all.nl Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-18hfsplus: validate b-tree node 0 bitmap at mount timeShardul Bankar
Syzkaller reported an issue with corrupted HFS+ images where the b-tree allocation bitmap indicates that the header node (Node 0) is free. Node 0 must always be allocated as it contains the b-tree header record and the allocation bitmap itself. Violating this invariant leads to allocator corruption, which cascades into kernel panics or undefined behavior when the filesystem attempts to allocate blocks. Prevent trusting a corrupted allocator state by adding a validation check during hfs_btree_open(). Introduce the hfs_bmap_test_bit() helper (utilizing the newly added map-access API) to safely verify that the MSB of the first bitmap byte (representing Node 0) is marked as allocated. The helper returns a boolean, allowing the caller to safely catch both structural IO errors and illegally cleared bits in a single check. If corruption is detected, print a warning identifying the specific corrupted tree and force the filesystem to mount read-only (SB_RDONLY). This prevents kernel panics from corrupted images while enabling data recovery. As a minor cleanup to support the warning logs, replace the verbose CNID logic with cleaner macro definitions (using official structural names like "Extents Overflow File") and a dedicated string lookup helper. Reported-by: syzbot+1c8ff72d0cd8a50dfeaa@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=1c8ff72d0cd8a50dfeaa Link: https://lore.kernel.org/all/20260315172005.2066677-1-shardul.b@mpiricsoftware.com/ Signed-off-by: Shardul Bankar <shardul.b@mpiricsoftware.com> Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com> Tested-by: Viacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com> Link: https://lore.kernel.org/r/20260318073823.3933718-3-shardul.b@mpiricsoftware.com Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
2026-03-18hfsplus: refactor b-tree map page access and add node-type validationShardul Bankar
In HFS+ b-trees, the node allocation bitmap is stored across multiple records. The first chunk resides in the b-tree Header Node at record index 2, while all subsequent chunks are stored in dedicated Map Nodes at record index 0. This structural quirk forces callers like hfs_bmap_alloc() and hfs_bmap_free() to duplicate boilerplate code to validate offsets, correct lengths, and map the underlying pages via kmap_local_page(). There is also currently no strict node-type validation before reading these records, leaving the allocator vulnerable if a corrupted image points a map linkage to an Index or Leaf node. Introduce a unified bit-level API to encapsulate the map record access: 1. A new `struct hfs_bmap_ctx` to cleanly pass state and safely handle page math across all architectures. 2. `hfs_bmap_get_map_page()`: Automatically validates node types (HFS_NODE_HEADER vs HFS_NODE_MAP), infers the correct record index, handles page-boundary math, and returns the unmapped `struct page *` directly to the caller to avoid asymmetric mappings. 3. `hfs_bmap_clear_bit()`: A clean wrapper that internally handles page mapping/unmapping for single-bit operations. Refactor hfs_bmap_alloc() and hfs_bmap_free() to utilize this new API. This deduplicates the allocator logic, hardens the map traversal against fuzzed images, and provides the exact abstractions needed for upcoming mount-time validation checks. Signed-off-by: Shardul Bankar <shardul.b@mpiricsoftware.com> Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com> Tested-by: Viacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com> Link: https://lore.kernel.org/r/20260318073823.3933718-2-shardul.b@mpiricsoftware.com Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
2026-03-18Merge tag 'nfsd-7.0-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux Pull nfsd fixes from Chuck Lever: - Fix cache_request leak in cache_release() - Fix heap overflow in the NFSv4.0 LOCK replay cache - Hold net reference for the lifetime of /proc/fs/nfs/exports fd - Defer sub-object cleanup in export "put" callbacks * tag 'nfsd-7.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: nfsd: fix heap overflow in NFSv4.0 LOCK replay cache sunrpc: fix cache_request leak in cache_release NFSD: Hold net reference for the lifetime of /proc/fs/nfs/exports fd NFSD: Defer sub-object cleanup in export put callbacks
2026-03-18fs/tests: exec: Remove bad test vectorKees Cook
Drop an unusable test in the bprm stack limits. Reported-by: Guenter Roeck <linux@roeck-us.net> Closes: https://lore.kernel.org/all/a3e9b1c2-40c1-45df-9fa2-14ee6a7b3fe2@roeck-us.net Fixes: 60371f43e56b ("exec: Add KUnit test for bprm_stack_limits()") Signed-off-by: Kees Cook <kees@kernel.org>
2026-03-19erofs: add GFP_NOIO in the bio completion if neededJiucheng Xu
The bio completion path in the process context (e.g. dm-verity) will directly call into decompression rather than trigger another workqueue context for minimal scheduling latencies, which can then call vm_map_ram() with GFP_KERNEL. Due to insufficient memory, vm_map_ram() may generate memory swapping I/O, which can cause submit_bio_wait to deadlock in some scenarios. Trimmed down the call stack, as follows: f2fs_submit_read_io submit_bio //bio_list is initialized. mmc_blk_mq_recovery z_erofs_endio vm_map_ram __pte_alloc_kernel __alloc_pages_direct_reclaim shrink_folio_list __swap_writepage submit_bio_wait //bio_list is non-NULL, hang!!! Use memalloc_noio_{save,restore}() to wrap up this path. Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2026-03-18Merge branch 'xfs-7.1-merge' into for-nextCarlos Maiolino
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18autofs: replace manual symlink buffer allocation in autofs_dir_symlinkThorsten Blum
The symlink name was previously duplicated using an explicit kmalloc() followed by strcpy(), which is deprecated [1]. Replace this open-coded string duplication with kstrdup(), which allocates and copies the symlink name with a single helper function. Remove the local variable 'size' and set 'i_size' directly using strlen(cp), which is equivalent to the previous value of 'size'. This simplifies the code, uses common string-handling helpers, and removes the deprecated use of strcpy(). Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1] Acked-by: Ian Kent <raven@themaw.net> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Link: https://patch.msgid.link/20260318001219.2354-3-thorsten.blum@linux.dev Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-18iomap: fix invalid folio access when i_blkbits differs from I/O granularityJoanne Koong
Commit aa35dd5cbc06 ("iomap: fix invalid folio access after folio_end_read()") partially addressed invalid folio access for folios without an ifs attached, but it did not handle the case where 1 << inode->i_blkbits matches the folio size but is different from the granularity used for the IO, which means IO can be submitted for less than the full folio for the !ifs case. In this case, the condition: if (*bytes_submitted == folio_len) ctx->cur_folio = NULL; in iomap_read_folio_iter() will not invalidate ctx->cur_folio, and iomap_read_end() will still be called on the folio even though the IO helper owns it and will finish the read on it. Fix this by unconditionally invalidating ctx->cur_folio for the !ifs case. Reported-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/linux-fsdevel/b3dfe271-4e3d-4922-b618-e73731242bca@wdc.com/ Fixes: b2f35ac4146d ("iomap: add caller-provided callbacks for read and readahead") Cc: stable@vger.kernel.org Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://patch.msgid.link/20260317203935.830549-1-joannelkoong@gmail.com Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-18xfs: avoid unnecessary calculations in xfs_zoned_need_gc()Damien Le Moal
If zonegc_low_space is set to zero (which is the default), the second condition in xfs_zoned_need_gc() that triggers GC never evaluates to true because the calculated threshold will always be 0. So there is no need to calculate the threshold and to evaluate that condition. Return early when zonegc_low_space is zero. While at it, add comments to document the intent of each of the 3 tests used to determine the return value to control the execution of garbage collection. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: display more zone related information in mountstatsDamien Le Moal
Modify xfs_zoned_show_stats() to add to the information displayed with /proc/self/mountstats the total number of zones (RT groups) and the number of open zones together with the maximum number of open zones. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: fix a comment typo in xfs_select_zone_nowait()Damien Le Moal
Fix a typo in the comment describing the second call to xfs_select_open_zone_lru() in xfs_select_zone_nowait(). Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: avoid unnecessary open zone check in xfs_select_zone_nowait()Damien Le Moal
When xfs_select_zone_nowait() is called with pack_tight equal to true, the function xfs_select_open_zone_mru() is called if no open zone is returned by xfs_select_open_zone_lru(), that is, when oz is NULL. The open zone pointer return of xfs_select_zone_nowait() is then checked, but this check is outside of the "if (pack_tight)" that trigered the call to xfs_select_open_zone_mru(). In other word, this check is unnecessarily done even when pack_tight is false. Move the check for the return value of the call to xfs_select_open_zone_mru() inside the if that controls the call to this function, so that we do not uselessly test again the value of oz when pack_tight is false. No functional changes. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: annotate struct xfs_attr_list_context with __counted_by_ptrBill Wendling
Add the `__counted_by_ptr` attribute to the `buffer` field of `struct xfs_attr_list_context`. This field is used to point to a buffer of size `bufsize`. The `buffer` field is assigned in: 1. `xfs_ioc_attr_list` in `fs/xfs/xfs_handle.c` 2. `xfs_xattr_list` in `fs/xfs/xfs_xattr.c` 3. `xfs_getparents` in `fs/xfs/xfs_handle.c` (implicitly initialized to NULL) In `xfs_ioc_attr_list`, `buffer` was assigned before `bufsize`. Reorder them to ensure `bufsize` is set before `buffer` is assigned, although no access happens between them. In `xfs_xattr_list`, `buffer` was assigned before `bufsize`. Reorder them to ensure `bufsize` is set before `buffer` is assigned. In `xfs_getparents`, `buffer` is NULL (from zero initialization) and remains NULL. `bufsize` is set to a non-zero value, but since `buffer` is NULL, no access occurs. In all cases, the pointer `buffer` is not accessed before `bufsize` is set. This patch was generated by CodeMender and reviewed by Bill Wendling. Tested by running xfstests. Signed-off-by: Bill Wendling <morbo@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: cleanup buftarg handling in XFS_IOC_VERIFY_MEDIAChristoph Hellwig
The newly added XFS_IOC_VERIFY_MEDIA is a bit unusual in how it handles buftarg fields. Update it to be more in line with other XFS code: - use btp->bt_dev instead of btp->bt_bdev->bd_dev to retrieve the device number for tracing - use btp->bt_logical_sectorsize instead of bdev_logical_block_size(btp->bt_bdev) to retrieve the logical sector size - compare the buftarg and not the bdev to see if there is a separate log buftarg Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: scrub: unlock dquot before early return in quota scrubhongao
xchk_quota_item can return early after calling xchk_fblock_process_error. When that helper returns false, the function returned immediately without dropping dq->q_qlock, which can leave the dquot lock held and risk lock leaks or deadlocks in later quota operations. Fix this by unlocking dq->q_qlock before the early return. Signed-off-by: hongao <hongao@uniontech.com> Fixes: 7d1f0e167a067e ("xfs: check the ondisk space mapping behind a dquot") Cc: <stable@vger.kernel.org> # v6.8 Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: refactor xfsaild_push loop into helperYuto Ohnuki
Factor the loop body of xfsaild_push() into a separate xfsaild_process_logitem() helper to improve readability. This is a pure code movement with no functional change. Signed-off-by: Yuto Ohnuki <ytohnuki@amazon.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: save ailp before dropping the AIL lock in push callbacksYuto Ohnuki
In xfs_inode_item_push() and xfs_qm_dquot_logitem_push(), the AIL lock is dropped to perform buffer IO. Once the cluster buffer no longer protects the log item from reclaim, the log item may be freed by background reclaim or the dquot shrinker. The subsequent spin_lock() call dereferences lip->li_ailp, which is a use-after-free. Fix this by saving the ailp pointer in a local variable while the AIL lock is held and the log item is guaranteed to be valid. Reported-by: syzbot+652af2b3c5569c4ab63c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=652af2b3c5569c4ab63c Fixes: 90c60e164012 ("xfs: xfs_iflush() is no longer necessary") Cc: stable@vger.kernel.org # v5.9 Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Yuto Ohnuki <ytohnuki@amazon.com> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: avoid dereferencing log items after push callbacksYuto Ohnuki
After xfsaild_push_item() calls iop_push(), the log item may have been freed if the AIL lock was dropped during the push. Background inode reclaim or the dquot shrinker can free the log item while the AIL lock is not held, and the tracepoints in the switch statement dereference the log item after iop_push() returns. Fix this by capturing the log item type, flags, and LSN before calling xfsaild_push_item(), and introducing a new xfs_ail_push_class trace event class that takes these pre-captured values and the ailp pointer instead of the log item pointer. Reported-by: syzbot+652af2b3c5569c4ab63c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=652af2b3c5569c4ab63c Fixes: 90c60e164012 ("xfs: xfs_iflush() is no longer necessary") Cc: stable@vger.kernel.org # v5.9 Signed-off-by: Yuto Ohnuki <ytohnuki@amazon.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: stop reclaim before pushing AIL during unmountYuto Ohnuki
The unmount sequence in xfs_unmount_flush_inodes() pushed the AIL while background reclaim and inodegc are still running. This is broken independently of any use-after-free issues - background reclaim and inodegc should not be running while the AIL is being pushed during unmount, as inodegc can dirty and insert inodes into the AIL during the flush, and background reclaim can race to abort and free dirty inodes. Reorder xfs_unmount_flush_inodes() to stop inodegc and cancel background reclaim before pushing the AIL. Stop inodegc before cancelling m_reclaim_work because the inodegc worker can re-queue m_reclaim_work via xfs_inodegc_set_reclaimable. Reported-by: syzbot+652af2b3c5569c4ab63c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=652af2b3c5569c4ab63c Fixes: 90c60e164012 ("xfs: xfs_iflush() is no longer necessary") Cc: stable@vger.kernel.org # v5.9 Signed-off-by: Yuto Ohnuki <ytohnuki@amazon.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-18xfs: opencode xfs_zone_record_blocksCarlos Maiolino
We only have a single caller, no need to keep it in its own function. Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com> [hch: add zone_record_blocks trace back] Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-03-17ksmbd: fix use-after-free in durable v2 replay of active file handlesHyunwoo Kim
parse_durable_handle_context() unconditionally assigns dh_info->fp->conn to the current connection when handling a DURABLE_REQ_V2 context with SMB2_FLAGS_REPLAY_OPERATION. ksmbd_lookup_fd_cguid() does not filter by fp->conn, so it returns file handles that are already actively connected. The unconditional overwrite replaces fp->conn, and when the overwriting connection is subsequently freed, __ksmbd_close_fd() dereferences the stale fp->conn via spin_lock(&fp->conn->llist_lock), causing a use-after-free. KASAN report: [ 7.349357] ================================================================== [ 7.349607] BUG: KASAN: slab-use-after-free in _raw_spin_lock+0x75/0xe0 [ 7.349811] Write of size 4 at addr ffff8881056ac18c by task kworker/1:2/108 [ 7.350010] [ 7.350064] CPU: 1 UID: 0 PID: 108 Comm: kworker/1:2 Not tainted 7.0.0-rc3+ #58 PREEMPTLAZY [ 7.350068] Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 7.350070] Workqueue: ksmbd-io handle_ksmbd_work [ 7.350083] Call Trace: [ 7.350087] <TASK> [ 7.350087] dump_stack_lvl+0x64/0x80 [ 7.350094] print_report+0xce/0x660 [ 7.350100] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 7.350101] ? __pfx___mod_timer+0x10/0x10 [ 7.350106] ? _raw_spin_lock+0x75/0xe0 [ 7.350108] kasan_report+0xce/0x100 [ 7.350109] ? _raw_spin_lock+0x75/0xe0 [ 7.350114] kasan_check_range+0x105/0x1b0 [ 7.350116] _raw_spin_lock+0x75/0xe0 [ 7.350118] ? __pfx__raw_spin_lock+0x10/0x10 [ 7.350119] ? __call_rcu_common.constprop.0+0x25e/0x780 [ 7.350125] ? close_id_del_oplock+0x2cc/0x4e0 [ 7.350128] __ksmbd_close_fd+0x27f/0xaf0 [ 7.350131] ksmbd_close_fd+0x135/0x1b0 [ 7.350133] smb2_close+0xb19/0x15b0 [ 7.350142] ? __pfx_smb2_close+0x10/0x10 [ 7.350143] ? xas_load+0x18/0x270 [ 7.350146] ? _raw_spin_lock+0x84/0xe0 [ 7.350148] ? __pfx__raw_spin_lock+0x10/0x10 [ 7.350150] ? _raw_spin_unlock+0xe/0x30 [ 7.350151] ? ksmbd_smb2_check_message+0xeb2/0x24c0 [ 7.350153] ? ksmbd_tree_conn_lookup+0xcd/0xf0 [ 7.350154] handle_ksmbd_work+0x40f/0x1080 [ 7.350156] process_one_work+0x5fa/0xef0 [ 7.350162] ? assign_work+0x122/0x3e0 [ 7.350163] worker_thread+0x54b/0xf70 [ 7.350165] ? __pfx_worker_thread+0x10/0x10 [ 7.350166] kthread+0x346/0x470 [ 7.350170] ? recalc_sigpending+0x19b/0x230 [ 7.350176] ? __pfx_kthread+0x10/0x10 [ 7.350178] ret_from_fork+0x4fb/0x6c0 [ 7.350183] ? __pfx_ret_from_fork+0x10/0x10 [ 7.350185] ? __switch_to+0x36c/0xbe0 [ 7.350188] ? __pfx_kthread+0x10/0x10 [ 7.350190] ret_from_fork_asm+0x1a/0x30 [ 7.350197] </TASK> [ 7.350197] [ 7.355160] Allocated by task 123: [ 7.355261] kasan_save_stack+0x33/0x60 [ 7.355373] kasan_save_track+0x14/0x30 [ 7.355484] __kasan_kmalloc+0x8f/0xa0 [ 7.355593] ksmbd_conn_alloc+0x44/0x6d0 [ 7.355711] ksmbd_kthread_fn+0x243/0xd70 [ 7.355839] kthread+0x346/0x470 [ 7.355942] ret_from_fork+0x4fb/0x6c0 [ 7.356051] ret_from_fork_asm+0x1a/0x30 [ 7.356164] [ 7.356214] Freed by task 134: [ 7.356305] kasan_save_stack+0x33/0x60 [ 7.356416] kasan_save_track+0x14/0x30 [ 7.356527] kasan_save_free_info+0x3b/0x60 [ 7.356646] __kasan_slab_free+0x43/0x70 [ 7.356761] kfree+0x1ca/0x430 [ 7.356862] ksmbd_tcp_disconnect+0x59/0xe0 [ 7.356993] ksmbd_conn_handler_loop+0x77e/0xd40 [ 7.357138] kthread+0x346/0x470 [ 7.357240] ret_from_fork+0x4fb/0x6c0 [ 7.357350] ret_from_fork_asm+0x1a/0x30 [ 7.357463] [ 7.357513] The buggy address belongs to the object at ffff8881056ac000 [ 7.357513] which belongs to the cache kmalloc-1k of size 1024 [ 7.357857] The buggy address is located 396 bytes inside of [ 7.357857] freed 1024-byte region [ffff8881056ac000, ffff8881056ac400) Fix by removing the unconditional fp->conn assignment and rejecting the replay when fp->conn is non-NULL. This is consistent with ksmbd_lookup_durable_fd(), which also rejects file handles with a non-NULL fp->conn. For disconnected file handles (fp->conn == NULL), ksmbd_reopen_durable_fd() handles setting fp->conn. Fixes: c8efcc786146 ("ksmbd: add support for durable handles v1/v2") Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Acked-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2026-03-17ksmbd: fix use-after-free of share_conf in compound requestHyunwoo Kim
smb2_get_ksmbd_tcon() reuses work->tcon in compound requests without validating tcon->t_state. ksmbd_tree_conn_lookup() checks t_state == TREE_CONNECTED on the initial lookup path, but the compound reuse path bypasses this check entirely. If a prior command in the compound (SMB2_TREE_DISCONNECT) sets t_state to TREE_DISCONNECTED and frees share_conf via ksmbd_share_config_put(), subsequent commands dereference the freed share_conf through work->tcon->share_conf. KASAN report: [ 4.144653] ================================================================== [ 4.145059] BUG: KASAN: slab-use-after-free in smb2_write+0xc74/0xe70 [ 4.145415] Read of size 4 at addr ffff88810430c194 by task kworker/1:1/44 [ 4.145772] [ 4.145867] CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted 7.0.0-rc3+ #60 PREEMPTLAZY [ 4.145871] Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 4.145875] Workqueue: ksmbd-io handle_ksmbd_work [ 4.145888] Call Trace: [ 4.145892] <TASK> [ 4.145894] dump_stack_lvl+0x64/0x80 [ 4.145910] print_report+0xce/0x660 [ 4.145919] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 4.145928] ? smb2_write+0xc74/0xe70 [ 4.145931] kasan_report+0xce/0x100 [ 4.145934] ? smb2_write+0xc74/0xe70 [ 4.145937] smb2_write+0xc74/0xe70 [ 4.145939] ? __pfx_smb2_write+0x10/0x10 [ 4.145942] ? _raw_spin_unlock+0xe/0x30 [ 4.145945] ? ksmbd_smb2_check_message+0xeb2/0x24c0 [ 4.145948] ? smb2_tree_disconnect+0x31c/0x480 [ 4.145951] handle_ksmbd_work+0x40f/0x1080 [ 4.145953] process_one_work+0x5fa/0xef0 [ 4.145962] ? assign_work+0x122/0x3e0 [ 4.145964] worker_thread+0x54b/0xf70 [ 4.145967] ? __pfx_worker_thread+0x10/0x10 [ 4.145970] kthread+0x346/0x470 [ 4.145976] ? recalc_sigpending+0x19b/0x230 [ 4.145980] ? __pfx_kthread+0x10/0x10 [ 4.145984] ret_from_fork+0x4fb/0x6c0 [ 4.145992] ? __pfx_ret_from_fork+0x10/0x10 [ 4.145995] ? __switch_to+0x36c/0xbe0 [ 4.145999] ? __pfx_kthread+0x10/0x10 [ 4.146003] ret_from_fork_asm+0x1a/0x30 [ 4.146013] </TASK> [ 4.146014] [ 4.149858] Allocated by task 44: [ 4.149953] kasan_save_stack+0x33/0x60 [ 4.150061] kasan_save_track+0x14/0x30 [ 4.150169] __kasan_kmalloc+0x8f/0xa0 [ 4.150274] ksmbd_share_config_get+0x1dd/0xdd0 [ 4.150401] ksmbd_tree_conn_connect+0x7e/0x600 [ 4.150529] smb2_tree_connect+0x2e6/0x1000 [ 4.150645] handle_ksmbd_work+0x40f/0x1080 [ 4.150761] process_one_work+0x5fa/0xef0 [ 4.150873] worker_thread+0x54b/0xf70 [ 4.150978] kthread+0x346/0x470 [ 4.151071] ret_from_fork+0x4fb/0x6c0 [ 4.151176] ret_from_fork_asm+0x1a/0x30 [ 4.151286] [ 4.151332] Freed by task 44: [ 4.151418] kasan_save_stack+0x33/0x60 [ 4.151526] kasan_save_track+0x14/0x30 [ 4.151634] kasan_save_free_info+0x3b/0x60 [ 4.151751] __kasan_slab_free+0x43/0x70 [ 4.151861] kfree+0x1ca/0x430 [ 4.151952] __ksmbd_tree_conn_disconnect+0xc8/0x190 [ 4.152088] smb2_tree_disconnect+0x1cd/0x480 [ 4.152211] handle_ksmbd_work+0x40f/0x1080 [ 4.152326] process_one_work+0x5fa/0xef0 [ 4.152438] worker_thread+0x54b/0xf70 [ 4.152545] kthread+0x346/0x470 [ 4.152638] ret_from_fork+0x4fb/0x6c0 [ 4.152743] ret_from_fork_asm+0x1a/0x30 [ 4.152853] [ 4.152900] The buggy address belongs to the object at ffff88810430c180 [ 4.152900] which belongs to the cache kmalloc-96 of size 96 [ 4.153226] The buggy address is located 20 bytes inside of [ 4.153226] freed 96-byte region [ffff88810430c180, ffff88810430c1e0) [ 4.153549] [ 4.153596] The buggy address belongs to the physical page: [ 4.153750] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88810430ce80 pfn:0x10430c [ 4.154000] flags: 0x100000000000200(workingset|node=0|zone=2) [ 4.154160] page_type: f5(slab) [ 4.154251] raw: 0100000000000200 ffff888100041280 ffff888100040110 ffff888100040110 [ 4.154461] raw: ffff88810430ce80 0000000800200009 00000000f5000000 0000000000000000 [ 4.154668] page dumped because: kasan: bad access detected [ 4.154820] [ 4.154866] Memory state around the buggy address: [ 4.155002] ffff88810430c080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 4.155196] ffff88810430c100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 4.155391] >ffff88810430c180: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 4.155587] ^ [ 4.155693] ffff88810430c200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 4.155891] ffff88810430c280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 4.156087] ================================================================== Add the same t_state validation to the compound reuse path, consistent with ksmbd_tree_conn_lookup(). Fixes: 5005bcb42191 ("ksmbd: validate session id and tree id in the compound request") Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Acked-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>