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

exfat: use exfat_chain_advance helper

2026-04-03T13:41:10+00:00

Replace open-coded cluster chain walking logic with exfat_chain_advance() across exfat_readdir, exfat_find_dir_entry, exfat_count_dir_entries, exfat_search_empty_slot and exfat_check_dir_empty. Signed-off-by: Chi Zhiling Reviewed-by: Sungjong Seo Reviewed-by: Yuezhang Mo Signed-off-by: Namjae Jeon

exfat: use exfat_cluster_walk helper

2026-04-03T13:41:05+00:00

Replace the custom exfat_walk_fat_chain() function and open-coded FAT chain walking logic with the exfat_cluster_walk() helper across exfat_find_location, __exfat_get_dentry_set, and exfat_map_cluster. Suggested-by: Sungjong Seo Signed-off-by: Chi Zhiling Reviewed-by: Sungjong Seo Reviewed-by: Yuezhang Mo Signed-off-by: Namjae Jeon

exfat: fix incorrect directory checksum after rename to shorter name

2026-04-03T13:41:02+00:00

When renaming a file in-place to a shorter name, exfat_remove_entries marks excess entries as DELETED, but es->num_entries is not updated accordingly. As a result, exfat_update_dir_chksum iterates over the deleted entries and computes an incorrect checksum. This does not lead to persistent corruption because mark_inode_dirty() is called afterward, and __exfat_write_inode later recomputes the checksum using the correct num_entries value. Fix by setting es->num_entries = num_entries in exfat_init_ext_entry. Signed-off-by: Chi Zhiling Reviewed-by: Sungjong Seo Reviewed-by: Yuezhang Mo Signed-off-by: Namjae Jeon

exfat: use readahead helper in exfat_get_dentry

2026-03-05T12:09:28+00:00

Replace the custom exfat_dir_readahead() function with the unified exfat_blk_readahead() helper in exfat_get_dentry(). This removes the duplicate readahead implementation and uses the common interface, also reducing code complexity. Signed-off-by: Chi Zhiling Signed-off-by: Namjae Jeon

exfat: Fix bitwise operation having different size

2026-03-04T10:23:59+00:00

cpos has type loff_t (long long), while s_blocksize has type u32. The inversion wil happen on u32, the coercion to s64 happens afterwards and will do 0-left-paddding, resulting in the upper bits getting masked out. Cast s_blocksize to loff_t before negating it. Found by static code analysis using Klocwork. Signed-off-by: Philipp Hahn Signed-off-by: Namjae Jeon

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: add setlease file operation

2026-01-12T09:55:46+00:00

Add the setlease file_operation to exfat_file_operations and exfat_dir_operations, pointing to generic_setlease. A future patch will change the default behavior to reject lease attempts with -EINVAL when there is no setlease file operation defined. Add generic_setlease to retain the ability to set leases on this filesystem. Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260108-setlease-6-20-v1-7-ea4dec9b67fa@kernel.org Acked-by: Namjae Jeon Acked-by: Al Viro Acked-by: Christoph Hellwig Signed-off-by: Christian Brauner

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: Add support for FS_IOC_{GET,SET}FSLABEL

2025-09-30T04:49:31+00:00

Add support for reading / writing to the exfat volume label from the FS_IOC_GETFSLABEL and FS_IOC_SETFSLABEL ioctls Co-developed-by: Yuezhang Mo Signed-off-by: Yuezhang Mo Signed-off-by: Ethan Ferguson Reviewed-by: Sungjong Seo 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