kernel/linux.git/fs/hfsplus, branch v6.12.92

hfsplus: fix held lock freed on hfsplus_fill_super()

2026-05-14T13:29:28+00:00

[ Upstream commit 90c500e4fd83fa33c09bc7ee23b6d9cc487ac733 ] hfsplus_fill_super() calls hfs_find_init() to initialize a search structure, which acquires tree->tree_lock. If the subsequent call to hfsplus_cat_build_key() fails, the function jumps to the out_put_root error label without releasing the lock. The later cleanup path then frees the tree data structure with the lock still held, triggering a held lock freed warning. Fix this by adding the missing hfs_find_exit(&fd) call before jumping to the out_put_root error label. This ensures that tree->tree_lock is properly released on the error path. The bug was originally detected on v6.13-rc1 using an experimental static analysis tool we are developing, and we have verified that the issue persists in the latest mainline kernel. The tool is specifically designed to detect memory management issues. It is currently under active development and not yet publicly available. We confirmed the bug by runtime testing under QEMU with x86_64 defconfig, lockdep enabled, and CONFIG_HFSPLUS_FS=y. To trigger the error path, we used GDB to dynamically shrink the max_unistr_len parameter to 1 before hfsplus_asc2uni() is called. This forces hfsplus_asc2uni() to naturally return -ENAMETOOLONG, which propagates to hfsplus_cat_build_key() and exercises the faulty error path. The following warning was observed during mount: ========================= WARNING: held lock freed! 7.0.0-rc3-00016-gb4f0dd314b39 #4 Not tainted ------------------------- mount/174 is freeing memory ffff888103f92000-ffff888103f92fff, with a lock still held there! ffff888103f920b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x154/0x1e0 2 locks held by mount/174: #0: ffff888103f960e0 (&type->s_umount_key#42/1){+.+.}-{4:4}, at: alloc_super.constprop.0+0x167/0xa40 #1: ffff888103f920b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x154/0x1e0 stack backtrace: CPU: 2 UID: 0 PID: 174 Comm: mount Not tainted 7.0.0-rc3-00016-gb4f0dd314b39 #4 PREEMPT(lazy) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 Call Trace: dump_stack_lvl+0x82/0xd0 debug_check_no_locks_freed+0x13a/0x180 kfree+0x16b/0x510 ? hfsplus_fill_super+0xcb4/0x18a0 hfsplus_fill_super+0xcb4/0x18a0 ? __pfx_hfsplus_fill_super+0x10/0x10 ? srso_return_thunk+0x5/0x5f ? bdev_open+0x65f/0xc30 ? srso_return_thunk+0x5/0x5f ? pointer+0x4ce/0xbf0 ? trace_contention_end+0x11c/0x150 ? __pfx_pointer+0x10/0x10 ? srso_return_thunk+0x5/0x5f ? bdev_open+0x79b/0xc30 ? srso_return_thunk+0x5/0x5f ? srso_return_thunk+0x5/0x5f ? vsnprintf+0x6da/0x1270 ? srso_return_thunk+0x5/0x5f ? __mutex_unlock_slowpath+0x157/0x740 ? __pfx_vsnprintf+0x10/0x10 ? srso_return_thunk+0x5/0x5f ? srso_return_thunk+0x5/0x5f ? mark_held_locks+0x49/0x80 ? srso_return_thunk+0x5/0x5f ? srso_return_thunk+0x5/0x5f ? irqentry_exit+0x17b/0x5e0 ? trace_irq_disable.constprop.0+0x116/0x150 ? __pfx_hfsplus_fill_super+0x10/0x10 ? __pfx_hfsplus_fill_super+0x10/0x10 get_tree_bdev_flags+0x302/0x580 ? __pfx_get_tree_bdev_flags+0x10/0x10 ? vfs_parse_fs_qstr+0x129/0x1a0 ? __pfx_vfs_parse_fs_qstr+0x3/0x10 vfs_get_tree+0x89/0x320 fc_mount+0x10/0x1d0 path_mount+0x5c5/0x21c0 ? __pfx_path_mount+0x10/0x10 ? trace_irq_enable.constprop.0+0x116/0x150 ? trace_irq_enable.constprop.0+0x116/0x150 ? srso_return_thunk+0x5/0x5f ? srso_return_thunk+0x5/0x5f ? kmem_cache_free+0x307/0x540 ? user_path_at+0x51/0x60 ? __x64_sys_mount+0x212/0x280 ? srso_return_thunk+0x5/0x5f __x64_sys_mount+0x212/0x280 ? __pfx___x64_sys_mount+0x10/0x10 ? srso_return_thunk+0x5/0x5f ? trace_irq_enable.constprop.0+0x116/0x150 ? srso_return_thunk+0x5/0x5f do_syscall_64+0x111/0x680 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ffacad55eae Code: 48 8b 0d 85 1f 0f 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00 8 RSP: 002b:00007fff1ab55718 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffacad55eae RDX: 000055740c64e5b0 RSI: 000055740c64e630 RDI: 000055740c651ab0 RBP: 000055740c64e380 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000055740c64e5b0 R14: 000055740c651ab0 R15: 000055740c64e380 After applying this patch, the warning no longer appears. Fixes: 89ac9b4d3d1a ("hfsplus: fix longname handling") CC: stable@vger.kernel.org Signed-off-by: Zilin Guan Reviewed-by: Viacheslav Dubeyko Tested-by: Viacheslav Dubeyko Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

hfsplus: fix uninit-value by validating catalog record size

2026-05-14T13:29:28+00:00

[ Upstream commit b6b592275aeff184aa82fcf6abccd833fb71b393 ] Syzbot reported a KMSAN uninit-value issue in hfsplus_strcasecmp(). The root cause is that hfs_brec_read() doesn't validate that the on-disk record size matches the expected size for the record type being read. When mounting a corrupted filesystem, hfs_brec_read() may read less data than expected. For example, when reading a catalog thread record, the debug output showed: HFSPLUS_BREC_READ: rec_len=520, fd->entrylength=26 HFSPLUS_BREC_READ: WARNING - entrylength (26) < rec_len (520) - PARTIAL READ! hfs_brec_read() only validates that entrylength is not greater than the buffer size, but doesn't check if it's less than expected. It successfully reads 26 bytes into a 520-byte structure and returns success, leaving 494 bytes uninitialized. This uninitialized data in tmp.thread.nodeName then gets copied by hfsplus_cat_build_key_uni() and used by hfsplus_strcasecmp(), triggering the KMSAN warning when the uninitialized bytes are used as array indices in case_fold(). Fix by introducing hfsplus_brec_read_cat() wrapper that: 1. Calls hfs_brec_read() to read the data 2. Validates the record size based on the type field: - Fixed size for folder and file records - Variable size for thread records (depends on string length) 3. Returns -EIO if size doesn't match expected For thread records, check against HFSPLUS_MIN_THREAD_SZ before reading nodeName.length to avoid reading uninitialized data at call sites that don't zero-initialize the entry structure. Also initialize the tmp variable in hfsplus_find_cat() as defensive programming to ensure no uninitialized data even if validation is bypassed. Reported-by: syzbot+d80abb5b890d39261e72@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d80abb5b890d39261e72 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Tested-by: syzbot+d80abb5b890d39261e72@syzkaller.appspotmail.com Reviewed-by: Viacheslav Dubeyko Tested-by: Viacheslav Dubeyko Suggested-by: Charalampos Mitrodimas Link: https://lore.kernel.org/all/20260120051114.1281285-1-kartikey406@gmail.com/ [v1] Link: https://lore.kernel.org/all/20260121063109.1830263-1-kartikey406@gmail.com/ [v2] Link: https://lore.kernel.org/all/20260212014233.2422046-1-kartikey406@gmail.com/ [v3] Link: https://lore.kernel.org/all/20260214002100.436125-1-kartikey406@gmail.com/T/ [v4] Link: https://lore.kernel.org/all/20260221061626.15853-1-kartikey406@gmail.com/T/ [v5] Signed-off-by: Deepanshu Kartikey Signed-off-by: Viacheslav Dubeyko Link: https://lore.kernel.org/r/20260307010302.41547-1-kartikey406@gmail.com Signed-off-by: Viacheslav Dubeyko Stable-dep-of: 90c500e4fd83 ("hfsplus: fix held lock freed on hfsplus_fill_super()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

hfsplus: pretend special inodes as regular files

2026-03-04T12:20:51+00:00

[ Upstream commit ed8889ca21b6ab37bc1435c4009ce37a79acb9e6 ] Since commit af153bb63a33 ("vfs: catch invalid modes in may_open()") requires any inode be one of S_IFDIR/S_IFLNK/S_IFREG/S_IFCHR/S_IFBLK/ S_IFIFO/S_IFSOCK type, use S_IFREG for special inodes. Reported-by: syzbot Closes: https://syzkaller.appspot.com/bug?extid=895c23f6917da440ed0d Signed-off-by: Tetsuo Handa Reviewed-by: Viacheslav Dubeyko Signed-off-by: Viacheslav Dubeyko Link: https://lore.kernel.org/r/d0a07b1b-8b73-4002-8e29-e2bd56871262@I-love.SAKURA.ne.jp Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin

hfsplus: fix volume corruption issue for generic/498

2026-03-04T12:20:51+00:00

[ Upstream commit 9a8c4ad44721da4c48e1ff240ac76286c82837fe ] The xfstests' test-case generic/498 leaves HFS+ volume in corrupted state: sudo ./check generic/498 FSTYP -- hfsplus PLATFORM -- Linux/x86_64 hfsplus-testing-0001 6.18.0-rc1+ #18 SMP PREEMPT_DYNAMIC Thu Dec 4 12:24:45 PST 2025 MKFS_OPTIONS -- /dev/loop51 MOUNT_OPTIONS -- /dev/loop51 /mnt/scratch generic/498 _check_generic_filesystem: filesystem on /dev/loop51 is inconsistent (see XFSTESTS-2/xfstests-dev/results//generic/498.full for details) Ran: generic/498 Failures: generic/498 Failed 1 of 1 tests sudo fsck.hfsplus -d /dev/loop51 ** /dev/loop51 Using cacheBlockSize=32K cacheTotalBlock=1024 cacheSize=32768K. Executing fsck_hfs (version 540.1-Linux). ** Checking non-journaled HFS Plus Volume. The volume name is untitled ** Checking extents overflow file. ** Checking catalog file. Invalid leaf record count (It should be 16 instead of 2) ** Checking multi-linked files. CheckHardLinks: found 1 pre-Leopard file inodes. ** Checking catalog hierarchy. ** Checking extended attributes file. ** Checking volume bitmap. ** Checking volume information. Verify Status: VIStat = 0x0000, ABTStat = 0x0000 EBTStat = 0x0000 CBTStat = 0x8000 CatStat = 0x00000000 ** Repairing volume. ** Rechecking volume. ** Checking non-journaled HFS Plus Volume. The volume name is untitled ** Checking extents overflow file. ** Checking catalog file. ** Checking multi-linked files. CheckHardLinks: found 1 pre-Leopard file inodes. ** Checking catalog hierarchy. ** Checking extended attributes file. ** Checking volume bitmap. ** Checking volume information. ** The volume untitled was repaired successfully. The generic/498 test executes such steps on final phase: mkdir $SCRATCH_MNT/A mkdir $SCRATCH_MNT/B mkdir $SCRATCH_MNT/A/C touch $SCRATCH_MNT/B/foo $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/B/foo ln $SCRATCH_MNT/B/foo $SCRATCH_MNT/A/C/foo $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/A "Simulate a power failure and mount the filesystem to check that what we explicitly fsync'ed exists." _flakey_drop_and_remount The FSCK tool complains about "Invalid leaf record count". HFS+ b-tree header contains leaf_count field is updated by hfs_brec_insert() and hfs_brec_remove(). The hfs_brec_insert() is involved into hard link creation process. However, modified in-core leaf_count field is stored into HFS+ b-tree header by hfs_btree_write() method. But, unfortunately, hfs_btree_write() hasn't been called by hfsplus_cat_write_inode() and hfsplus_file_fsync() stores not fully consistent state of the Catalog File's b-tree. This patch adds calling hfs_btree_write() method in the hfsplus_cat_write_inode() with the goal of storing consistent state of Catalog File's b-tree. Finally, it makes FSCK tool happy. sudo ./check generic/498 FSTYP -- hfsplus PLATFORM -- Linux/x86_64 hfsplus-testing-0001 6.18.0-rc1+ #22 SMP PREEMPT_DYNAMIC Sat Dec 6 17:01:31 PST 2025 MKFS_OPTIONS -- /dev/loop51 MOUNT_OPTIONS -- /dev/loop51 /mnt/scratch generic/498 33s ... 31s Ran: generic/498 Passed all 1 tests Signed-off-by: Viacheslav Dubeyko cc: John Paul Adrian Glaubitz cc: Yangtao Li cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20251207035821.3863657-1-slava@dubeyko.com Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin

hfsplus: return error when node already exists in hfs_bnode_create

2026-03-04T12:19:21+00:00

[ Upstream commit d8a73cc46c8462a969a7516131feb3096f4c49d3 ] When hfs_bnode_create() finds that a node is already hashed (which should not happen in normal operation), it currently returns the existing node without incrementing its reference count. This causes a reference count inconsistency that leads to a kernel panic when the node is later freed in hfs_bnode_put(): kernel BUG at fs/hfsplus/bnode.c:676! BUG_ON(!atomic_read(&node->refcnt)) This scenario can occur when hfs_bmap_alloc() attempts to allocate a node that is already in use (e.g., when node 0's bitmap bit is incorrectly unset), or due to filesystem corruption. Returning an existing node from a create path is not normal operation. Fix this by returning ERR_PTR(-EEXIST) instead of the node when it's already hashed. This properly signals the error condition to callers, which already check for IS_ERR() return values. Reported-by: syzbot+1c8ff72d0cd8a50dfeaa@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=1c8ff72d0cd8a50dfeaa Link: https://lore.kernel.org/all/784415834694f39902088fa8946850fc1779a318.camel@ibm.com/ Fixes: 634725a92938 ("[PATCH] hfs: cleanup HFS+ prints") Signed-off-by: Shardul Bankar Reviewed-by: Viacheslav Dubeyko Signed-off-by: Viacheslav Dubeyko Link: https://lore.kernel.org/r/20251229204938.1907089-1-shardul.b@mpiricsoftware.com Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin

hfsplus: fix slab-out-of-bounds read in hfsplus_uni2asc()

2026-02-11T12:40:18+00:00

commit bea3e1d4467bcf292c8e54f080353d556d355e26 upstream. BUG: KASAN: slab-out-of-bounds in hfsplus_uni2asc+0xa71/0xb90 fs/hfsplus/unicode.c:186 Read of size 2 at addr ffff8880289ef218 by task syz.6.248/14290 CPU: 0 UID: 0 PID: 14290 Comm: syz.6.248 Not tainted 6.16.4 #1 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1b0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x5f0 mm/kasan/report.c:482 kasan_report+0xca/0x100 mm/kasan/report.c:595 hfsplus_uni2asc+0xa71/0xb90 fs/hfsplus/unicode.c:186 hfsplus_listxattr+0x5b6/0xbd0 fs/hfsplus/xattr.c:738 vfs_listxattr+0xbe/0x140 fs/xattr.c:493 listxattr+0xee/0x190 fs/xattr.c:924 filename_listxattr fs/xattr.c:958 [inline] path_listxattrat+0x143/0x360 fs/xattr.c:988 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcb/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe0e9fae16d Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe0eae67f98 EFLAGS: 00000246 ORIG_RAX: 00000000000000c3 RAX: ffffffffffffffda RBX: 00007fe0ea205fa0 RCX: 00007fe0e9fae16d RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000000 RBP: 00007fe0ea0480f0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe0ea206038 R14: 00007fe0ea205fa0 R15: 00007fe0eae48000 Allocated by task 14290: kasan_save_stack+0x24/0x50 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4333 [inline] __kmalloc_noprof+0x219/0x540 mm/slub.c:4345 kmalloc_noprof include/linux/slab.h:909 [inline] hfsplus_find_init+0x95/0x1f0 fs/hfsplus/bfind.c:21 hfsplus_listxattr+0x331/0xbd0 fs/hfsplus/xattr.c:697 vfs_listxattr+0xbe/0x140 fs/xattr.c:493 listxattr+0xee/0x190 fs/xattr.c:924 filename_listxattr fs/xattr.c:958 [inline] path_listxattrat+0x143/0x360 fs/xattr.c:988 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcb/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f When hfsplus_uni2asc is called from hfsplus_listxattr, it actually passes in a struct hfsplus_attr_unistr*. The size of the corresponding structure is different from that of hfsplus_unistr, so the previous fix (94458781aee6) is insufficient. The pointer on the unicode buffer is still going beyond the allocated memory. This patch introduces two warpper functions hfsplus_uni2asc_xattr_str and hfsplus_uni2asc_str to process two unicode buffers, struct hfsplus_attr_unistr* and struct hfsplus_unistr* respectively. When ustrlen value is bigger than the allocated memory size, the ustrlen value is limited to an safe size. Fixes: 94458781aee6 ("hfsplus: fix slab-out-of-bounds read in hfsplus_uni2asc()") Signed-off-by: Kang Chen Reviewed-by: Viacheslav Dubeyko Signed-off-by: Viacheslav Dubeyko Link: https://lore.kernel.org/r/20250909031316.1647094-1-k.chen@smail.nju.edu.cn Signed-off-by: Viacheslav Dubeyko Signed-off-by: Jianqiang kang Signed-off-by: Greg Kroah-Hartman

hfsplus: fix volume corruption issue for generic/073

2026-01-08T09:13:57+00:00

[ Upstream commit 24e17a29cf7537f0947f26a50f85319abd723c6c ] The xfstests' test-case generic/073 leaves HFS+ volume in corrupted state: sudo ./check generic/073 FSTYP -- hfsplus PLATFORM -- Linux/x86_64 hfsplus-testing-0001 6.17.0-rc1+ #4 SMP PREEMPT_DYNAMIC Wed Oct 1 15:02:44 PDT 2025 MKFS_OPTIONS -- /dev/loop51 MOUNT_OPTIONS -- /dev/loop51 /mnt/scratch generic/073 _check_generic_filesystem: filesystem on /dev/loop51 is inconsistent (see XFSTESTS-2/xfstests-dev/results//generic/073.full for details) Ran: generic/073 Failures: generic/073 Failed 1 of 1 tests sudo fsck.hfsplus -d /dev/loop51 ** /dev/loop51 Using cacheBlockSize=32K cacheTotalBlock=1024 cacheSize=32768K. Executing fsck_hfs (version 540.1-Linux). ** Checking non-journaled HFS Plus Volume. The volume name is untitled ** Checking extents overflow file. ** Checking catalog file. ** Checking multi-linked files. ** Checking catalog hierarchy. Invalid directory item count (It should be 1 instead of 0) ** Checking extended attributes file. ** Checking volume bitmap. ** Checking volume information. Verify Status: VIStat = 0x0000, ABTStat = 0x0000 EBTStat = 0x0000 CBTStat = 0x0000 CatStat = 0x00004000 ** Repairing volume. ** Rechecking volume. ** Checking non-journaled HFS Plus Volume. The volume name is untitled ** Checking extents overflow file. ** Checking catalog file. ** Checking multi-linked files. ** Checking catalog hierarchy. ** Checking extended attributes file. ** Checking volume bitmap. ** Checking volume information. ** The volume untitled was repaired successfully. The test is doing these steps on final phase: mv $SCRATCH_MNT/testdir_1/bar $SCRATCH_MNT/testdir_2/bar $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/testdir_1 $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo So, we move file bar from testdir_1 into testdir_2 folder. It means that HFS+ logic decrements the number of entries in testdir_1 and increments number of entries in testdir_2. Finally, we do fsync only for testdir_1 and foo but not for testdir_2. As a result, this is the reason why fsck.hfsplus detects the volume corruption afterwards. This patch fixes the issue by means of adding the hfsplus_cat_write_inode() call for old_dir and new_dir in hfsplus_rename() after the successful ending of hfsplus_rename_cat(). This method makes modification of in-core inode objects for old_dir and new_dir but it doesn't save these modifications in Catalog File's entries. It was expected that hfsplus_write_inode() will save these modifications afterwards. However, because generic/073 does fsync only for testdir_1 and foo then testdir_2 modification hasn't beed saved into Catalog File's entry and it was flushed without this modification. And it was detected by fsck.hfsplus. Now, hfsplus_rename() stores in Catalog File all modified entries and correct state of Catalog File will be flushed during hfsplus_file_fsync() call. Finally, it makes fsck.hfsplus happy. sudo ./check generic/073 FSTYP -- hfsplus PLATFORM -- Linux/x86_64 hfsplus-testing-0001 6.18.0-rc3+ #93 SMP PREEMPT_DYNAMIC Wed Nov 12 14:37:49 PST 2025 MKFS_OPTIONS -- /dev/loop51 MOUNT_OPTIONS -- /dev/loop51 /mnt/scratch generic/073 32s ... 32s Ran: generic/073 Passed all 1 tests Signed-off-by: Viacheslav Dubeyko cc: John Paul Adrian Glaubitz cc: Yangtao Li cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20251112232522.814038-1-slava@dubeyko.com Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin

hfsplus: Verify inode mode when loading from disk

2026-01-08T09:13:57+00:00

[ Upstream commit 005d4b0d33f6b4a23d382b7930f7a96b95b01f39 ] syzbot is reporting that S_IFMT bits of inode->i_mode can become bogus when the S_IFMT bits of the 16bits "mode" field loaded from disk are corrupted. According to [1], the permissions field was treated as reserved in Mac OS 8 and 9. According to [2], the reserved field was explicitly initialized with 0, and that field must remain 0 as long as reserved. Therefore, when the "mode" field is not 0 (i.e. no longer reserved), the file must be S_IFDIR if dir == 1, and the file must be one of S_IFREG/S_IFLNK/S_IFCHR/ S_IFBLK/S_IFIFO/S_IFSOCK if dir == 0. Reported-by: syzbot Closes: https://syzkaller.appspot.com/bug?extid=895c23f6917da440ed0d Link: https://developer.apple.com/library/archive/technotes/tn/tn1150.html#HFSPlusPermissions [1] Link: https://developer.apple.com/library/archive/technotes/tn/tn1150.html#ReservedAndPadFields [2] Signed-off-by: Tetsuo Handa Reviewed-by: Viacheslav Dubeyko Signed-off-by: Viacheslav Dubeyko Link: https://lore.kernel.org/r/04ded9f9-73fb-496c-bfa5-89c4f5d1d7bb@I-love.SAKURA.ne.jp Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin

hfsplus: fix missing hfs_bnode_get() in __hfs_bnode_create

2026-01-08T09:13:57+00:00

[ Upstream commit 152af114287851583cf7e0abc10129941f19466a ] When sync() and link() are called concurrently, both threads may enter hfs_bnode_find() without finding the node in the hash table and proceed to create it. Thread A: hfsplus_write_inode() -> hfsplus_write_system_inode() -> hfs_btree_write() -> hfs_bnode_find(tree, 0) -> __hfs_bnode_create(tree, 0) Thread B: hfsplus_create_cat() -> hfs_brec_insert() -> hfs_bnode_split() -> hfs_bmap_alloc() -> hfs_bnode_find(tree, 0) -> __hfs_bnode_create(tree, 0) In this case, thread A creates the bnode, sets refcnt=1, and hashes it. Thread B also tries to create the same bnode, notices it has already been inserted, drops its own instance, and uses the hashed one without getting the node. ``` node2 = hfs_bnode_findhash(tree, cnid); if (!node2) { <- Thread A hash = hfs_bnode_hash(cnid); node->next_hash = tree->node_hash[hash]; tree->node_hash[hash] = node; tree->node_hash_cnt++; } else { <- Thread B spin_unlock(&tree->hash_lock); kfree(node); wait_event(node2->lock_wq, !test_bit(HFS_BNODE_NEW, &node2->flags)); return node2; } ``` However, hfs_bnode_find() requires each call to take a reference. Here both threads end up setting refcnt=1. When they later put the node, this triggers: BUG_ON(!atomic_read(&node->refcnt)) In this scenario, Thread B in fact finds the node in the hash table rather than creating a new one, and thus must take a reference. Fix this by calling hfs_bnode_get() when reusing a bnode newly created by another thread to ensure the refcount is updated correctly. A similar bug was fixed in HFS long ago in commit a9dc087fd3c4 ("fix missing hfs_bnode_get() in __hfs_bnode_create") but the same issue remained in HFS+ until now. Reported-by: syzbot+005d2a9ecd9fbf525f6a@syzkaller.appspotmail.com Signed-off-by: Yang Chenzhi Signed-off-by: Viacheslav Dubeyko Link: https://lore.kernel.org/r/20250829093912.611853-1-yang.chenzhi@vivo.com Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin

hfsplus: fix volume corruption issue for generic/070

2026-01-08T09:13:57+00:00

[ Upstream commit ed490f36f439b877393c12a2113601e4145a5a56 ] The xfstests' test-case generic/070 leaves HFS+ volume in corrupted state: sudo ./check generic/070 FSTYP -- hfsplus PLATFORM -- Linux/x86_64 hfsplus-testing-0001 6.17.0-rc1+ #4 SMP PREEMPT_DYNAMIC Wed Oct 1 15:02:44 PDT 2025 MKFS_OPTIONS -- /dev/loop51 MOUNT_OPTIONS -- /dev/loop51 /mnt/scratch generic/070 _check_generic_filesystem: filesystem on /dev/loop50 is inconsistent (see xfstests-dev/results//generic/070.full for details) Ran: generic/070 Failures: generic/070 Failed 1 of 1 tests sudo fsck.hfsplus -d /dev/loop50 ** /dev/loop50 Using cacheBlockSize=32K cacheTotalBlock=1024 cacheSize=32768K. Executing fsck_hfs (version 540.1-Linux). ** Checking non-journaled HFS Plus Volume. The volume name is test ** Checking extents overflow file. Unused node is not erased (node = 1) ** Checking catalog file. ** Checking multi-linked files. ** Checking catalog hierarchy. ** Checking extended attributes file. ** Checking volume bitmap. ** Checking volume information. Verify Status: VIStat = 0x0000, ABTStat = 0x0000 EBTStat = 0x0004 CBTStat = 0x0000 CatStat = 0x00000000 ** Repairing volume. ** Rechecking volume. ** Checking non-journaled HFS Plus Volume. The volume name is test ** Checking extents overflow file. ** Checking catalog file. ** Checking multi-linked files. ** Checking catalog hierarchy. ** Checking extended attributes file. ** Checking volume bitmap. ** Checking volume information. ** The volume test was repaired successfully. It is possible to see that fsck.hfsplus detected not erased and unused node for the case of extents overflow file. The HFS+ logic has special method that defines if the node should be erased: bool hfs_bnode_need_zeroout(struct hfs_btree *tree) { struct super_block *sb = tree->inode->i_sb; struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb); const u32 volume_attr = be32_to_cpu(sbi->s_vhdr->attributes); return tree->cnid == HFSPLUS_CAT_CNID && volume_attr & HFSPLUS_VOL_UNUSED_NODE_FIX; } However, it is possible to see that this method works only for the case of catalog file. But debugging of the issue has shown that HFSPLUS_VOL_UNUSED_NODE_FIX attribute has been requested for the extents overflow file too: catalog file kernel: hfsplus: node 4, num_recs 0, flags 0x10 kernel: hfsplus: tree->cnid 4, volume_attr 0x80000800 extents overflow file kernel: hfsplus: node 1, num_recs 0, flags 0x10 kernel: hfsplus: tree->cnid 3, volume_attr 0x80000800 This patch modifies the hfs_bnode_need_zeroout() by checking only volume_attr but not the b-tree ID because node zeroing can be requested for all HFS+ b-tree types. sudo ./check generic/070 FSTYP -- hfsplus PLATFORM -- Linux/x86_64 hfsplus-testing-0001 6.18.0-rc3+ #79 SMP PREEMPT_DYNAMIC Fri Oct 31 16:07:42 PDT 2025 MKFS_OPTIONS -- /dev/loop51 MOUNT_OPTIONS -- /dev/loop51 /mnt/scratch generic/070 33s ... 34s Ran: generic/070 Passed all 1 tests Signed-off-by: Viacheslav Dubeyko cc: John Paul Adrian Glaubitz cc: Yangtao Li cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20251101001229.247432-1-slava@dubeyko.com Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin