kernel/linux.git/fs/exfat/super.c, branch linux-7.1.y

exfat: fix s_maxbytes

2026-03-31T14:01:07+00:00

With fallocate support, xfstest unit generic/213 fails with QA output created by 213 We should get: fallocate: No space left on device Strangely, xfs_io sometimes says "Success" when something went wrong -fallocate: No space left on device +fallocate: File too large because sb->s_maxbytes is set to the volume size. To be in line with other non-extent-based filesystems, set to max volume size possible with the cluster size of the volume. Signed-off-by: David Timber Signed-off-by: Namjae Jeon

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

exfat: fix remount failure in different process environments

2025-12-03T01:00:17+00:00

The kernel test robot reported that the exFAT remount operation failed. The reason for the failure was that the process's umask is different between mount and remount, causing fs_fmask and fs_dmask are changed. Potentially, both gid and uid may also be changed. Therefore, when initializing fs_context for remount, inherit these mount options from the options used during mount. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202511251637.81670f5c-lkp@intel.com Signed-off-by: Yuezhang Mo Signed-off-by: Namjae Jeon

exfat: validate the cluster bitmap bits of directory

2025-12-03T01:00:16+00:00

Syzbot created this issue by testing an image that did not have the root cluster bitmap bit marked. After accessing a file through the root directory via exfat_lookup, when creating a file again with mkdir, the root cluster bit can be allocated for direcotry, which can cause the root cluster to be zeroed out and the same entry can be allocated in the same cluster. This patch improved this issue by adding exfat_test_bitmap to validate the cluster bits of the root directory and directory. And the first cluster bit of the root directory should never be unset except when storage is corrupted. This bit is set to allow operations after mount. Reported-by: syzbot+5216036fc59c43d1ee02@syzkaller.appspotmail.com Tested-by: syzbot+5216036fc59c43d1ee02@syzkaller.appspotmail.com Reviewed-by: Sungjong Seo Reviewed-by: Yuezhang Mo Signed-off-by: Namjae Jeon

exfat: check return value of sb_min_blocksize in exfat_read_boot_sector

2025-11-05T13:00:16+00:00

sb_min_blocksize() may return 0. Check its return value to avoid accessing the filesystem super block when sb->s_blocksize is 0. Cc: stable@vger.kernel.org # v6.15 Fixes: 719c1e1829166d ("exfat: add super block operations") Reviewed-by: Christoph Hellwig Signed-off-by: Yongpeng Yang Link: https://patch.msgid.link/20251104125009.2111925-3-yangyongpeng.storage@gmail.com Signed-off-by: Christian Brauner

exfat: combine iocharset and utf8 option setup

2025-09-30T04:41:22+00:00

Currently, exfat utf8 mount option depends on the iocharset option value. After exfat remount, utf8 option may become inconsistent with iocharset option. If the options are inconsistent; (specifically, iocharset=utf8 but utf8=0) readdir may reference uninitalized NLS, leading to a null pointer dereference. Extract and combine utf8/iocharset setup logic into exfat_set_iocharset(). Then Replace iocharset setup logic to exfat_set_iocharset to prevent utf8/iocharset option inconsistentcy after remount. Reported-by: syzbot+3e9cb93e3c5f90d28e19@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=3e9cb93e3c5f90d28e19 Signed-off-by: Sang-Heon Jeon Fixes: acab02ffcd6b ("exfat: support modifying mount options via remount") Tested-by: syzbot+3e9cb93e3c5f90d28e19@syzkaller.appspotmail.com Reviewed-by: Yuezhang Mo Signed-off-by: Namjae Jeon

exfat: support modifying mount options via remount

2025-09-30T04:34:43+00:00

Before this commit, all exfat-defined mount options could not be modified dynamically via remount, and no error was returned. After this commit, these three exfat-defined mount options (discard, zero_size_dir, and errors) can be modified dynamically via remount. While other exfat-defined mount options cannot be modified dynamically via remount because their old settings are cached in inodes or dentries, modifying them will be rejected with an error. Signed-off-by: Yuezhang Mo Signed-off-by: Namjae Jeon

exfat: add cluster chain loop check for dir

2025-07-31T23:34:23+00:00

An infinite loop may occur if the following conditions occur due to file system corruption. (1) Condition for exfat_count_dir_entries() to loop infinitely. - The cluster chain includes a loop. - There is no UNUSED entry in the cluster chain. (2) Condition for exfat_create_upcase_table() to loop infinitely. - The cluster chain of the root directory includes a loop. - There are no UNUSED entry and up-case table entry in the cluster chain of the root directory. (3) Condition for exfat_load_bitmap() to loop infinitely. - The cluster chain of the root directory includes a loop. - There are no UNUSED entry and bitmap entry in the cluster chain of the root directory. (4) Condition for exfat_find_dir_entry() to loop infinitely. - The cluster chain includes a loop. - The unused directory entries were exhausted by some operation. (5) Condition for exfat_check_dir_empty() to loop infinitely. - The cluster chain includes a loop. - The unused directory entries were exhausted by some operation. - All files and sub-directories under the directory are deleted. This commit adds checks to break the above infinite loop. Signed-off-by: Yuezhang Mo Signed-off-by: Namjae Jeon

new helper: set_default_d_op()

2025-06-11T02:21:16+00:00

... to be used instead of manually assigning to ->s_d_op. All in-tree filesystem converted (and field itself is renamed, so any out-of-tree ones in need of conversion will be caught by compiler). Reviewed-by: Christian Brauner Signed-off-by: Al Viro