kernel/git/next/linux-next.git/fs/fat, branch master

Merge branch 'fs-next' of linux-next

2026-09-11T12:19:54+00:00

fat: calculate data area start without overflow

2026-09-11T03:22:15+00:00

On 32-bit architectures, sbi->fat_length, sbi->dir_start and sbi->data_start are unsigned long. The number of FATs is an 8-bit BPB field, while the FAT32 length is a 32-bit BPB field. Therefore, the calculation sbi->fat_start + sbi->fats * sbi->fat_length can wrap before data_start is checked against total_sectors. For example, with fat_start=32, fats=2 and fat_length=0x80000001, the unwrapped data area start is 0x100000022 (4294967330), but the calculation wraps to 34 on i386. With total_sectors=36, the validation then incorrectly passes. The following script creates an image that demonstrates the problem: python3 - <<'PY' import struct S = 512 b = bytearray(36 * S) def p(off, fmt, value): struct.pack_into(fmt, b, off, value) # FAT32 BPB b[0:3] = b'\xeb\x58\x90' b[3:11] = b'MSWIN4.1' p(11, ' Acked-by: OGAWA Hirofumi Signed-off-by: Andrew Morton

fat: fix fat_ent_write() for reverting the value

2026-09-11T03:22:02+00:00

commit 64d9183203ee ("fat: restore original value when fat_ent_write failed") try to revert the fatent value to old value when got the error on mirror FAT. However it didn't work if the error is when writing the fatent bh. In that case, the bh is cleared the uptodate flag, so reuse bh is invalid. Fix this by reverting the fatent only if got the error on mirror FAT. Link: https://lore.kernel.org/87ik4yz9fv.fsf_-_@mail.parknet.co.jp Fixes: 64d9183203ee ("fat: restore original value when fat_ent_write failed") Signed-off-by: OGAWA Hirofumi Reported-by: syzbot+e64c6472a3d96a75172a@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=e64c6472a3d96a75172a Reported-by: syzbot+26461e903494e689c24f@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=26461e903494e689c24f Cc: Yemu Lu Cc: Ren Wei Cc: Yuan Tan Cc: Yifan Wu Cc: Juefei Pu Cc: Xin Liu Cc: Signed-off-by: Andrew Morton

fat: check for a metadata write error with buffer_write_io_error()

2026-08-31T08:19:22+00:00

fat_sync_bhs() waits for the writes it issued and then tests !buffer_uptodate() to find the ones that failed. That relies on the write completion handler clearing BH_Uptodate on error, which this series removes: a buffer whose write failed still holds the data the filesystem asked to be written, so declaring it not up to date is wrong and makes callers re-read it. Test BH_Write_EIO, which is what the completion handler sets and what this code actually wants to know. No behaviour change today - a failed write sets BH_Write_EIO and clears BH_Uptodate together. It stops being a no-op at the end of the series, where the new test is the one that still works. Acked-by: Weidong Zhu Signed-off-by: Chao Shi Link: https://patch.msgid.link/4b6019b5a48b83c8235918b084248983a57692e1.1785951556.git.coshi036@gmail.com Reviewed-by: Jan Kara Signed-off-by: Christian Brauner (Amutable)

Merge tag 'mm-nonmm-stable-2026-08-22-16-57' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-08-23T15:07:11+00:00

Pull non-MM updates from Andrew Morton: - "ocfs2/dlm: bound peer-controlled lengths in the o2dlm" (Bryam Vargas) Validate and bound all input lengths and count fields in the o2dlm migration and recovery receive handlers to prevent memory corruption and kernel panics from malformed cluster messages - "ocfs2: validate xattr entry bounds" (Cen Zhang) Validate OCFS2 extended attribute entry name and value bounds during metadata reads to prevent out-of-range memory accesses during retrieval or listing operations. - "taskstats: fix cgroupstats invalid fd handling and add selftests" (Yiyang Chen) Return -EBADF when cgroupstats receives an invalid file descriptor to prevent caller hangs and misleading success ACKs. Add a kselftest to validate valid cgroup v1 queries and verify proper error handling across different Netlink flag combinations. - "misc lib/raid/ improvements v2" (Christoph Hellwig) Improve benchmark-based algorithm selection for the XOR and RAID6 libraries, add KUnit benchmark tests, and cleanup minor implementation details. - "ocfs2: cluster: o2hb_region_pin() fixes" (Joseph Qi) Fix sleeping-in-atomic, lock order inversion and error-path cleanup bugs in o2hb_region_pin() by releasing o2hb_live_lock across sleeping configfs_depend_item() calls and using unlocked variants from callback context. Ensure failed pin attempts properly decrement user counts and unpin partially initialized heartbeat regions to prevent memory leaks and unprotected states. - "lib/ucs2_string.c: fix out-of-bounds read in ucs2_strnlen()" (Vincent Mailhol) Fix an off-by-one which could cause an out-of-bounds read. - "ocfs2: harden heartbeat teardown races" (Cen Zhang) Fix two OCFS2 heartbeat/o2net teardown races found by KASAN. - "taskstats: tidy up the cpumask command path" *Bradley Morgan) make two small cleanups in kernel/taskstats.c. - "ocfs2: validate active orphan slots during inode read" (ZhengYuan Huang) Validate active ordinary and append-DIO orphan slots read from OCFS2 dinodes at the metadata boundary to prevent corrupted slot indices from causing out-of-bounds array accesses. - "ocfs2: bound-check both readdir re-validation scans" (Zhan Xusheng) Enforce strict boundary checks on directory entry record lengths and offset calculations during OCFS2 directory re-scans to prevent out-of-bounds memory reads and directory position corruption. * tag 'mm-nonmm-stable-2026-08-22-16-57' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (95 commits) mailmap: fix bouncing address for Taniya Das ocfs2: bound-check dir entries in the inline-data re-validation scan ocfs2: bound-check dir entries in the readdir re-validation scan squashfs: avoid thundering-herd cache wakeups prctl: fix PR_SET_MM_AUXV losing the forced AT_NULL terminator mailmap: update email address for Linfeng Sun lib/interval_tree: fix allocation warning messages checkpatch: add NOKPROBE_SYMBOL to the whitelist of lines that can occur immediately after functions Squashfs: check block offset is not negative signal: factor out the kernel reserved si_code check ocfs2: fix readdir position truncation on 32-bit kernels ocfs2: fix cached cluster count after suballocator reclaim ocfs2: fix circular locking dependency in ocfs2_init_acl() ocfs2: validate DIO orphan slot during inode read ocfs2: validate orphan slot during inode read selftests/prctl: fix non-anonymous VMA mapping in set-anon-vma-name test MAINTAINERS: add IRC and patchwork for LTP include/linux/list.h: mark list_add and __list_add as __always_inline tools/mm: prevent page_owner_sort from truncating input hung_task: update DETECT_HUNG_TASK_BLOCKER Kconfig help ...

Merge tag 'vfs-7.3-rc1.sync' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-08-17T21:21:00+00:00

Pull vfs writeback updates from Christian Brauner: "This makes sync_inode_metadata() and writeback_single_inode() persist not only the inode but all metadata associated with it. A new .sync_inode_metadata superblock operation is called from __writeback_single_inode(). Alongside it a new I_METADATA_WRITEBACK state flag is added. Filesystems no longer need their own mmb_fsync() implementations and can just use simple_fsync(). All metadata is now written for IS_SYNC and IS_DIRSYNC inodes. Races where several fsyncs raced and mmb_sync() could return before all buffers were really persisted are fixed since I_SYNC now serializes properly. The I_METADATA_WRITEBACK scheme also fixes the case where a WB_SYNC_NONE writeback landing between write(2) and fsync(2) left fsync(2) failing to persist the inode. That problem is not specific to filesystems using the generic metadata bh tracking, and the ones that do not are left alone. ext2, udf, bfs, minix, fat and ext4 in nojournal mode have their data integrity writeout fixed and are converted. affs drops metadata bh tracking and mmb_fsync() is removed. A few other fixes came out of this: - a UAF in mark_buffer_write_io_error() - missed inode writeback when racing with __writeback_single_inode() - ext4 allocating the mapping_metadata_bhs struct on demand - three fat fixes: a lost inode update in do_msdos_rename() with DIRSYNC, inode buffer write errors not propagating out of fat_sync_inode_metadata() and directory entries not being persisted on fsync(2) of the root directory" * tag 'vfs-7.3-rc1.sync' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (24 commits) writeback: Export __inode_attach_wb() fat: Fix persisting directory entries on fsync(2) of the root directory fat: Propagate inode buffer write errors from fat_sync_inode_metadata() fat: Fix lost inode update in do_msdos_rename() with DIRSYNC vfs: Remove mmb_fsync() fat: Replace fat_sync_inode() with sync_inode_metadata() fat: Fix missed inode writeback during fsync(2) ext4: Fix data integrity writeout issues in nojournal mode minix: Fix data integrity writeout issues bfs: Fix data integrity writeout issues udf: Fold udf_update_inode() into udf_write_inode() udf: Use sync_inode_metadata() in udf_evict_inode() udf: Drop udf_sync_inode() udf: Use sync_inode_metadata() to writeout IS_SYNC inode udf: Fix data integrity writeout issues ext2: Fix data integrity writeout issues ext2: Avoid unnecessary inode buffer writeback for sync(2) ext2: Drop __ext2_write_inode() ext2: Fix lost inode updates for IS_SYNC inodes fs: Provide way for filesystem to wait for metadata writeback ...

Merge tag 'vfs-7.3-rc1.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-08-17T19:03:34+00:00

Pull vfs lookup updates from Christian Brauner: "This refactors lookup_open() and adds vfs_lookup_open() for nfsd. mnt_want_write() and parent locking are moved into lookup_open() itself. audit_inode_child() is also now called in lookup_open() on failure. That is the calling convention in vfs_create() and vfs_mkdir(), but lookup_open() made no such call when atomic_open() should have created a file and did not. And neither did the regular ->create() path fwiw. This also contains work to remove the unneeded excl argument from the ->create() inode op" * tag 'vfs-7.3-rc1.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs/namei.c: fix coding style in atomic_open() and lookup_open() fs/namei.c: fix kerneldoc of atomic_open() and vfs_lookup_open() fs/namei.c: update stale comments in lookup_open() Remove excl arg to ->create inode_operation fs/namei.c: update kerneldoc of atomic_open() vfs: call audit_inode_child() in lookup_open() on failure vfs: move create error && negative dentry case in lookup_open() up VFS: add vfs_lookup_open() for nfsd VFS: move delegated_inode retry loop into lookup_open() VFS: move mnt_want_write() and locking into lookup_open()

Merge tag 'vfs-7.3-rc1.fat' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-08-17T16:30:42+00:00

Pull FAT update from Christian Brauner: "This rejects names longer than NAME_MAX in msdos_format_name(). The VFS only enforces PATH_MAX rather than the length of an individual component. open() on such a path component reported success for a name far longer than NAME_MAX" * tag 'vfs-7.3-rc1.fat' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fat: reject name longer than NAME_MAX in msdos_format_name()

fat: release buffer head after rebuilding parent

2026-08-04T04:10:17+00:00

fat_scan_logstart() leaves the matching directory entry's buffer head in sinfo.bh for the caller to release, just like fat_scan(). fat_rebuild_parent() uses the directory entry to rebuild the parent inode for the nostale_ro NFS export path, but does not release sinfo.bh after a successful scan. Release it once fat_build_inode() has consumed the directory entry data. Link: https://lore.kernel.org/20260715020957.1096309-1-chenyichong@uniontech.com Fixes: f1e6fb0ab451 ("fat (exportfs): rebuild directory-inode if fat_dget()") Signed-off-by: Yichong Chen Acked-by: OGAWA Hirofumi Cc: Christian Brauner Cc: Amit Sahrawat Cc: chenyichong Cc: Namjae Jeon Cc: Ravishankar N Signed-off-by: Andrew Morton

FAT: allow 0xE9 near jump in fat_read_static_bpb()

2026-08-04T04:10:14+00:00

fat_read_static_bpb() only accepts a short jump as a valid bootstrap code signature for DOS 1.x volumes when the dos1xfloppy mount option is used. However, according to the Microsoft fatgen103.doc, the BS_jmpBoot field has two allowed forms: 0xEB 0x?? 0x90 (short jump + NOP) and 0xE9 0x?? 0x?? (near jump). The specification explicitly states that either form is acceptable. This patch relaxes the check to also accept 0xE9 as the first byte of the jump instruction. Link: https://lore.kernel.org/20260412070109.5197-1-zhangcoder@yeah.net Signed-off-by: Ziran Zhang Acked-by: OGAWA Hirofumi Cc: Christian Brauner Signed-off-by: Andrew Morton