kernel/linux.git/fs/ext4/ialloc.c, branch v5.10.257

ext4: make recently_deleted() properly work with lazy itable initialization

2026-04-18T08:31:07+00:00

commit bd060afa7cc3e0ad30afa9ecc544a78638498555 upstream. recently_deleted() checks whether inode has been used in the near past. However this can give false positive result when inode table is not initialized yet and we are in fact comparing to random garbage (or stale itable block of a filesystem before mkfs). Ultimately this results in uninitialized inodes being skipped during inode allocation and possibly they are never initialized and thus e2fsck complains. Verify if the inode has been initialized before checking for dtime. Signed-off-by: Jan Kara Reviewed-by: Zhang Yi Link: https://patch.msgid.link/20260216164848.3074-3-jack@suse.cz Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: avoid negative min_clusters in find_group_orlov()

2024-10-17T13:07:51+00:00

[ Upstream commit bb0a12c3439b10d88412fd3102df5b9a6e3cd6dc ] min_clusters is signed integer and will be converted to unsigned integer when compared with unsigned number stats.free_clusters. If min_clusters is negative, it will be converted to a huge unsigned value in which case all groups may not meet the actual desired free clusters. Set negative min_clusters to 0 to avoid unexpected behavior. Fixes: ac27a0ec112a ("[PATCH] ext4: initial copy of files from ext3") Signed-off-by: Kemeng Shi Link: https://patch.msgid.link/20240820132234.2759926-4-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: avoid potential buffer_head leak in __ext4_new_inode()

2024-10-17T13:07:50+00:00

[ Upstream commit 227d31b9214d1b9513383cf6c7180628d4b3b61f ] If a group is marked EXT4_GROUP_INFO_IBITMAP_CORRUPT after it's inode bitmap buffer_head was successfully verified, then __ext4_new_inode() will get a valid inode_bitmap_bh of a corrupted group from ext4_read_inode_bitmap() in which case inode_bitmap_bh misses a release. Hnadle "IS_ERR(inode_bitmap_bh)" and group corruption separately like how ext4_free_inode() does to avoid buffer_head leak. Fixes: 9008a58e5dce ("ext4: make the bitmap read routines return real error codes") Signed-off-by: Kemeng Shi Link: https://patch.msgid.link/20240820132234.2759926-3-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: avoid buffer_head leak in ext4_mark_inode_used()

2024-10-17T13:07:50+00:00

[ Upstream commit 5e5b2a56c57def1b41efd49596621504d7bcc61c ] Release inode_bitmap_bh from ext4_read_inode_bitmap() in ext4_mark_inode_used() to avoid buffer_head leak. By the way, remove unneeded goto for invalid ino when inode_bitmap_bh is NULL. Fixes: 8016e29f4362 ("ext4: fast commit recovery path") Signed-off-by: Kemeng Shi Link: https://patch.msgid.link/20240820132234.2759926-2-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: allow ext4_get_group_info() to fail

2023-05-30T11:57:47+00:00

[ Upstream commit 5354b2af34064a4579be8bc0e2f15a7b70f14b5f ] Previously, ext4_get_group_info() would treat an invalid group number as BUG(), since in theory it should never happen. However, if a malicious attaker (or fuzzer) modifies the superblock via the block device while it is the file system is mounted, it is possible for s_first_data_block to get set to a very large number. In that case, when calculating the block group of some block number (such as the starting block of a preallocation region), could result in an underflow and very large block group number. Then the BUG_ON check in ext4_get_group_info() would fire, resutling in a denial of service attack that can be triggered by root or someone with write access to the block device. For a quality of implementation perspective, it's best that even if the system administrator does something that they shouldn't, that it will not trigger a BUG. So instead of BUG'ing, ext4_get_group_info() will call ext4_error and return NULL. We also add fallback code in all of the callers of ext4_get_group_info() that it might NULL. Also, since ext4_get_group_info() was already borderline to be an inline function, un-inline it. The results in a next reduction of the compiled text size of ext4 by roughly 2k. Cc: stable@kernel.org Link: https://lore.kernel.org/r/20230430154311.579720-2-tytso@mit.edu Reported-by: syzbot+e2efa3efc15a1c9e95c3@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?id=69b28112e098b070f639efb356393af3ffec4220 Signed-off-by: Theodore Ts'o Reviewed-by: Jan Kara Signed-off-by: Sasha Levin

ext4: make directory inode spreading reflect flexbg size

2022-09-28T09:10:41+00:00

commit 613c5a85898d1cd44e68f28d65eccf64a8ace9cf upstream. Currently the Orlov inode allocator searches for free inodes for a directory only in flex block groups with at most inodes_per_group/16 more directory inodes than average per flex block group. However with growing size of flex block group this becomes unnecessarily strict. Scale allowed difference from average directory count per flex block group with flex block group size as we do with other metrics. Tested-by: Stefan Wahren Tested-by: Ojaswin Mujoo Cc: stable@kernel.org Link: https://lore.kernel.org/all/0d81a7c2-46b7-6010-62a4-3e6cfc1628d6@i2se.com/ Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20220908092136.11770-3-jack@suse.cz Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: fix avefreec in find_group_orlov

2021-07-14T14:55:41+00:00

commit c89849cc0259f3d33624cc3bd127685c3c0fa25d upstream. The avefreec should be average free clusters instead of average free blocks, otherwize Orlov's allocator will not work properly when bigalloc enabled. Cc: stable@kernel.org Signed-off-by: Pan Dong Link: https://lore.kernel.org/r/20210525073656.31594-1-pandong.peter@bytedance.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: fix accessing uninit percpu counter variable with fast_commit

2021-06-10T11:39:26+00:00

commit b45f189a19b38e01676628db79cd3eeb1333516e upstream. When running generic/527 with fast_commit configuration, the following issue is seen on Power. With fast_commit, during ext4_fc_replay() (which can be called from ext4_fill_super()), if inode eviction happens then it can access an uninitialized percpu counter variable. This patch adds the check before accessing the counters in ext4_free_inode() path. [ 321.165371] run fstests generic/527 at 2021-04-29 08:38:43 [ 323.027786] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: block_validity. Quota mode: none. [ 323.618772] BUG: Unable to handle kernel data access on read at 0x1fbd80000 [ 323.619767] Faulting instruction address: 0xc000000000bae78c cpu 0x1: Vector: 300 (Data Access) at [c000000010706ef0] pc: c000000000bae78c: percpu_counter_add_batch+0x3c/0x100 lr: c0000000006d0bb0: ext4_free_inode+0x780/0xb90 pid = 5593, comm = mount ext4_free_inode+0x780/0xb90 ext4_evict_inode+0xa8c/0xc60 evict+0xfc/0x1e0 ext4_fc_replay+0xc50/0x20f0 do_one_pass+0xfe0/0x1350 jbd2_journal_recover+0x184/0x2e0 jbd2_journal_load+0x1c0/0x4a0 ext4_fill_super+0x2458/0x4200 mount_bdev+0x1dc/0x290 ext4_mount+0x28/0x40 legacy_get_tree+0x4c/0xa0 vfs_get_tree+0x4c/0x120 path_mount+0xcf8/0xd70 do_mount+0x80/0xd0 sys_mount+0x3fc/0x490 system_call_exception+0x384/0x3d0 system_call_common+0xec/0x278 Cc: stable@kernel.org Fixes: 8016e29f4362 ("ext4: fast commit recovery path") Signed-off-by: Ritesh Harjani Reviewed-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/6cceb9a75c54bef8fa9696c1b08c8df5ff6169e2.1619692410.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: allow the dax flag to be set and cleared on inline directories

2021-05-11T12:47:38+00:00

commit 4811d9929cdae4238baf5b2522247bd2f9fa7b50 upstream. This is needed to allow generic/607 to pass for file systems with the inline data_feature enabled, and it allows the use of file systems where the directories use inline_data, while the files are accessed via DAX. Cc: stable@kernel.org Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: fix check to prevent false positive report of incorrect used inodes

2021-05-11T12:47:37+00:00

commit a149d2a5cabbf6507a7832a1c4fd2593c55fd450 upstream. Commit <50122847007> ("ext4: fix check to prevent initializing reserved inodes") check the block group zero and prevent initializing reserved inodes. But in some special cases, the reserved inode may not all belong to the group zero, it may exist into the second group if we format filesystem below. mkfs.ext4 -b 4096 -g 8192 -N 1024 -I 4096 /dev/sda So, it will end up triggering a false positive report of a corrupted file system. This patch fix it by avoid check reserved inodes if no free inode blocks will be zeroed. Cc: stable@kernel.org Fixes: 50122847007 ("ext4: fix check to prevent initializing reserved inodes") Signed-off-by: Zhang Yi Suggested-by: Jan Kara Link: https://lore.kernel.org/r/20210331121516.2243099-1-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman