kernel/linux.git/fs/ext4/ioctl.c, branch v6.1.168

ext4: mark group extend fast-commit ineligible

2026-03-04T12:20:26+00:00

[ Upstream commit 1f8dd813a1c771b13c303f73d876164bc9b327cc ] Fast commits only log operations that have dedicated replay support. EXT4_IOC_GROUP_EXTEND grows the filesystem to the end of the last block group and updates the same on-disk metadata without going through the fast commit tracking paths. In practice these operations are rare and usually followed by further updates, but mixing them into a fast commit makes the overall semantics harder to reason about and risks replay gaps if new call sites appear. Teach ext4 to mark the filesystem fast-commit ineligible when EXT4_IOC_GROUP_EXTEND grows the filesystem. This forces those transactions to fall back to a full commit, ensuring that the group extension changes are captured by the normal journal rather than partially encoded in fast commit TLVs. This change should not affect common workloads but makes online resize via GROUP_EXTEND safer and easier to reason about under fast commit. Testing: 1. prepare: dd if=/dev/zero of=/root/fc_resize.img bs=1M count=0 seek=256 mkfs.ext4 -O fast_commit -F /root/fc_resize.img mkdir -p /mnt/fc_resize && mount -t ext4 -o loop /root/fc_resize.img /mnt/fc_resize 2. Extended the filesystem to the end of the last block group using a helper that calls EXT4_IOC_GROUP_EXTEND on the mounted filesystem and checked fc_info: ./group_extend_helper /mnt/fc_resize cat /proc/fs/ext4/loop0/fc_info shows the "Resize" ineligible reason increased. 3. Fsynced a file on the resized filesystem and confirmed that the fast commit ineligible counter incremented for the resize transaction: touch /mnt/fc_resize/file /root/fsync_file /mnt/fc_resize/file sync cat /proc/fs/ext4/loop0/fc_info Signed-off-by: Li Chen Link: https://patch.msgid.link/20251211115146.897420-6-me@linux.beauty Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: mark group add fast-commit ineligible

2026-03-04T12:20:26+00:00

[ Upstream commit 89b4336fd5ec78f51f9d3a1d100f3ffa3228e604 ] Fast commits only log operations that have dedicated replay support. Online resize via EXT4_IOC_GROUP_ADD updates the superblock and group descriptor metadata without going through the fast commit tracking paths. In practice these operations are rare and usually followed by further updates, but mixing them into a fast commit makes the overall semantics harder to reason about and risks replay gaps if new call sites appear. Teach ext4 to mark the filesystem fast-commit ineligible when ext4_ioctl_group_add() adds new block groups. This forces those transactions to fall back to a full commit, ensuring that the filesystem geometry updates are captured by the normal journal rather than partially encoded in fast commit TLVs. This change should not affect common workloads but makes online resize via GROUP_ADD safer and easier to reason about under fast commit. Testing: 1. prepare: dd if=/dev/zero of=/root/fc_resize.img bs=1M count=0 seek=256 mkfs.ext4 -O fast_commit -F /root/fc_resize.img mkdir -p /mnt/fc_resize && mount -t ext4 -o loop /root/fc_resize.img /mnt/fc_resize 2. Ran a helper that issues EXT4_IOC_GROUP_ADD on the mounted filesystem and checked the resize ineligible reason: ./group_add_helper /mnt/fc_resize cat /proc/fs/ext4/loop0/fc_info shows "Resize": > 0. 3. Fsynced a file on the resized filesystem and verified that the fast commit stats report at least one ineligible commit: touch /mnt/fc_resize/file /root/fsync_file /mnt/fc_resize/file sync cat /proc/fs/ext4/loop0/fc_info shows fc stats ineligible > 0. Signed-off-by: Li Chen Link: https://patch.msgid.link/20251211115146.897420-5-me@linux.beauty Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: fix to check return value of freeze_bdev() in ext4_shutdown()

2023-07-23T11:49:34+00:00

commit c4d13222afd8a64bf11bc7ec68645496ee8b54b9 upstream. freeze_bdev() can fail due to a lot of reasons, it needs to check its reason before later process. Fixes: 783d94854499 ("ext4: add EXT4_IOC_GOINGDOWN ioctl") Cc: stable@kernel.org Signed-off-by: Chao Yu Link: https://lore.kernel.org/r/20230606073203.1310389-1-chao@kernel.org Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: zero i_disksize when initializing the bootloader inode

2023-03-17T07:50:16+00:00

commit f5361da1e60d54ec81346aee8e3d8baf1be0b762 upstream. If the boot loader inode has never been used before, the EXT4_IOC_SWAP_BOOT inode will initialize it, including setting the i_size to 0. However, if the "never before used" boot loader has a non-zero i_size, then i_disksize will be non-zero, and the inconsistency between i_size and i_disksize can trigger a kernel warning: WARNING: CPU: 0 PID: 2580 at fs/ext4/file.c:319 CPU: 0 PID: 2580 Comm: bb Not tainted 6.3.0-rc1-00004-g703695902cfa RIP: 0010:ext4_file_write_iter+0xbc7/0xd10 Call Trace: vfs_write+0x3b1/0x5c0 ksys_write+0x77/0x160 __x64_sys_write+0x22/0x30 do_syscall_64+0x39/0x80 Reproducer: 1. create corrupted image and mount it: mke2fs -t ext4 /tmp/foo.img 200 debugfs -wR "sif <5> size 25700" /tmp/foo.img mount -t ext4 /tmp/foo.img /mnt cd /mnt echo 123 > file 2. Run the reproducer program: posix_memalign(&buf, 1024, 1024) fd = open("file", O_RDWR | O_DIRECT); ioctl(fd, EXT4_IOC_SWAP_BOOT); write(fd, buf, 1024); Fix this by setting i_disksize as well as i_size to zero when initiaizing the boot loader inode. Link: https://bugzilla.kernel.org/show_bug.cgi?id=217159 Cc: stable@kernel.org Signed-off-by: Zhihao Cheng Link: https://lore.kernel.org/r/20230308032643.641113-1-chengzhihao1@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: initialize quota before expanding inode in setproject ioctl

2023-01-07T10:12:02+00:00

commit 1485f726c6dec1a1f85438f2962feaa3d585526f upstream. Make sure we initialize quotas before possibly expanding inode space (and thus maybe needing to allocate external xattr block) in ext4_ioctl_setproject(). This prevents not accounting the necessary block allocation. Signed-off-by: Jan Kara Cc: stable@kernel.org Link: https://lore.kernel.org/r/20221207115937.26601-1-jack@suse.cz Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: dont return EINVAL from GETFSUUID when reporting UUID length

2023-01-07T10:12:01+00:00

commit b76abb5157468756163fe7e3431c9fe32cba57ca upstream. If userspace calls this ioctl with fsu_length (the length of the fsuuid.fsu_uuid array) set to zero, ext4 copies the desired uuid length out to userspace. The kernel call returned a result from a valid input, so the return value here should be zero, not EINVAL. While we're at it, fix the copy_to_user call to make it clear that we're only copying out fsu_len. Signed-off-by: Darrick J. Wong Reviewed-by: Catherine Hoang Link: https://lore.kernel.org/r/166811138914.327006.9241306894437166566.stgit@magnolia Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: don't fail GETFSUUID when the caller provides a long buffer

2023-01-07T10:12:01+00:00

commit a7e9d977e031fceefe1e7cd69ebd7202d5758b56 upstream. If userspace provides a longer UUID buffer than is required, we shouldn't fail the call with EINVAL -- rather, we can fill the caller's buffer with the bytes we /can/ fill, and update the length field to reflect what we copied. This doesn't break the UAPI since we're enabling a case that currently fails, and so far Ted hasn't released a version of e2fsprogs that uses the new ext4 ioctl. Signed-off-by: Darrick J. Wong Reviewed-by: Catherine Hoang Link: https://lore.kernel.org/r/166811139478.327006.13879198441587445544.stgit@magnolia Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: fix bug_on in __es_tree_search caused by bad boot loader inode

2023-01-07T10:11:59+00:00

commit 991ed014de0840c5dc405b679168924afb2952ac upstream. We got a issue as fllows: ================================================================== kernel BUG at fs/ext4/extents_status.c:203! invalid opcode: 0000 [#1] PREEMPT SMP CPU: 1 PID: 945 Comm: cat Not tainted 6.0.0-next-20221007-dirty #349 RIP: 0010:ext4_es_end.isra.0+0x34/0x42 RSP: 0018:ffffc9000143b768 EFLAGS: 00010203 RAX: 0000000000000000 RBX: ffff8881769cd0b8 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8fc27cf7 RDI: 00000000ffffffff RBP: ffff8881769cd0bc R08: 0000000000000000 R09: ffffc9000143b5f8 R10: 0000000000000001 R11: 0000000000000001 R12: ffff8881769cd0a0 R13: ffff8881768e5668 R14: 00000000768e52f0 R15: 0000000000000000 FS: 00007f359f7f05c0(0000)GS:ffff88842fd00000(0000)knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f359f5a2000 CR3: 000000017130c000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __es_tree_search.isra.0+0x6d/0xf5 ext4_es_cache_extent+0xfa/0x230 ext4_cache_extents+0xd2/0x110 ext4_find_extent+0x5d5/0x8c0 ext4_ext_map_blocks+0x9c/0x1d30 ext4_map_blocks+0x431/0xa50 ext4_mpage_readpages+0x48e/0xe40 ext4_readahead+0x47/0x50 read_pages+0x82/0x530 page_cache_ra_unbounded+0x199/0x2a0 do_page_cache_ra+0x47/0x70 page_cache_ra_order+0x242/0x400 ondemand_readahead+0x1e8/0x4b0 page_cache_sync_ra+0xf4/0x110 filemap_get_pages+0x131/0xb20 filemap_read+0xda/0x4b0 generic_file_read_iter+0x13a/0x250 ext4_file_read_iter+0x59/0x1d0 vfs_read+0x28f/0x460 ksys_read+0x73/0x160 __x64_sys_read+0x1e/0x30 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd ================================================================== In the above issue, ioctl invokes the swap_inode_boot_loader function to swap inode<5> and inode<12>. However, inode<5> contain incorrect imode and disordered extents, and i_nlink is set to 1. The extents check for inode in the ext4_iget function can be bypassed bacause 5 is EXT4_BOOT_LOADER_INO. While links_count is set to 1, the extents are not initialized in swap_inode_boot_loader. After the ioctl command is executed successfully, the extents are swapped to inode<12>, in this case, run the `cat` command to view inode<12>. And Bug_ON is triggered due to the incorrect extents. When the boot loader inode is not initialized, its imode can be one of the following: 1) the imode is a bad type, which is marked as bad_inode in ext4_iget and set to S_IFREG. 2) the imode is good type but not S_IFREG. 3) the imode is S_IFREG. The BUG_ON may be triggered by bypassing the check in cases 1 and 2. Therefore, when the boot loader inode is bad_inode or its imode is not S_IFREG, initialize the inode to avoid triggering the BUG. Signed-off-by: Baokun Li Reviewed-by: Jason Yan Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20221026042310.3839669-5-libaokun1@huawei.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: add EXT4_IGET_BAD flag to prevent unexpected bad inode

2023-01-07T10:11:58+00:00

commit 63b1e9bccb71fe7d7e3ddc9877dbdc85e5d2d023 upstream. There are many places that will get unhappy (and crash) when ext4_iget() returns a bad inode. However, if iget the boot loader inode, allows a bad inode to be returned, because the inode may not be initialized. This mechanism can be used to bypass some checks and cause panic. To solve this problem, we add a special iget flag EXT4_IGET_BAD. Only with this flag we'd be returning bad inode from ext4_iget(), otherwise we always return the error code if the inode is bad inode.(suggested by Jan Kara) Signed-off-by: Baokun Li Reviewed-by: Jason Yan Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20221026042310.3839669-4-libaokun1@huawei.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2022-11-06T18:30:29+00:00

Pull ext4 fixes from Ted Ts'o: "Fix a number of bugs, including some regressions, the most serious of which was one which would cause online resizes to fail with file systems with metadata checksums enabled. Also fix a warning caused by the newly added fortify string checker, plus some bugs that were found using fuzzed file systems" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: fix fortify warning in fs/ext4/fast_commit.c:1551 ext4: fix wrong return err in ext4_load_and_init_journal() ext4: fix warning in 'ext4_da_release_space' ext4: fix BUG_ON() when directory entry has invalid rec_len ext4: update the backup superblock's at the end of the online resize