kernel/linux.git/fs/ext4/extents.c, branch linux-6.0.y

ext4: fix delayed allocation bug in ext4_clu_mapped for bigalloc + inline

2023-01-07T10:16:03+00:00

commit 131294c35ed6f777bd4e79d42af13b5c41bf2775 upstream. When converting files with inline data to extents, delayed allocations made on a file system created with both the bigalloc and inline options can result in invalid extent status cache content, incorrect reserved cluster counts, kernel memory leaks, and potential kernel panics. With bigalloc, the code that determines whether a block must be delayed allocated searches the extent tree to see if that block maps to a previously allocated cluster. If not, the block is delayed allocated, and otherwise, it isn't. However, if the inline option is also used, and if the file containing the block is marked as able to store data inline, there isn't a valid extent tree associated with the file. The current code in ext4_clu_mapped() calls ext4_find_extent() to search the non-existent tree for a previously allocated cluster anyway, which typically finds nothing, as desired. However, a side effect of the search can be to cache invalid content from the non-existent tree (garbage) in the extent status tree, including bogus entries in the pending reservation tree. To fix this, avoid searching the extent tree when allocating blocks for bigalloc + inline files that are being converted from inline to extent mapped. Signed-off-by: Eric Whitney Link: https://lore.kernel.org/r/20221117152207.2424-1-enwlinux@gmail.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: fix use-after-free in ext4_ext_shift_extents

2022-12-02T16:43:10+00:00

commit f6b1a1cf1c3ee430d3f5e47847047ce789a690aa upstream. If the starting position of our insert range happens to be in the hole between the two ext4_extent_idx, because the lblk of the ext4_extent in the previous ext4_extent_idx is always less than the start, which leads to the "extent" variable access across the boundary, the following UAF is triggered: ================================================================== BUG: KASAN: use-after-free in ext4_ext_shift_extents+0x257/0x790 Read of size 4 at addr ffff88819807a008 by task fallocate/8010 CPU: 3 PID: 8010 Comm: fallocate Tainted: G E 5.10.0+ #492 Call Trace: dump_stack+0x7d/0xa3 print_address_description.constprop.0+0x1e/0x220 kasan_report.cold+0x67/0x7f ext4_ext_shift_extents+0x257/0x790 ext4_insert_range+0x5b6/0x700 ext4_fallocate+0x39e/0x3d0 vfs_fallocate+0x26f/0x470 ksys_fallocate+0x3a/0x70 __x64_sys_fallocate+0x4f/0x60 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ================================================================== For right shifts, we can divide them into the following situations： 1. When the first ee_block of ext4_extent_idx is greater than or equal to start, make right shifts directly from the first ee_block. 1) If it is greater than start, we need to continue searching in the previous ext4_extent_idx. 2) If it is equal to start, we can exit the loop (iterator=NULL). 2. When the first ee_block of ext4_extent_idx is less than start, then traverse from the last extent to find the first extent whose ee_block is less than start. 1) If extent is still the last extent after traversal, it means that the last ee_block of ext4_extent_idx is less than start, that is, start is located in the hole between idx and (idx+1), so we can exit the loop directly (break) without right shifts. 2) Otherwise, make right shifts at the corresponding position of the found extent, and then exit the loop (iterator=NULL). Fixes: 331573febb6a ("ext4: Add support FALLOC_FL_INSERT_RANGE for fallocate") Cc: stable@vger.kernel.org # v4.2+ Signed-off-by: Zhihao Cheng Signed-off-by: Baokun Li Link: https://lore.kernel.org/r/20220922120434.1294789-1-libaokun1@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: fix bug in extents parsing when eh_entries == 0 and eh_depth > 0

2022-09-22T14:50:54+00:00

When walking through an inode extents, the ext4_ext_binsearch_idx() function assumes that the extent header has been previously validated. However, there are no checks that verify that the number of entries (eh->eh_entries) is non-zero when depth is > 0. And this will lead to problems because the EXT_FIRST_INDEX() and EXT_LAST_INDEX() will return garbage and result in this: [ 135.245946] ------------[ cut here ]------------ [ 135.247579] kernel BUG at fs/ext4/extents.c:2258! [ 135.249045] invalid opcode: 0000 [#1] PREEMPT SMP [ 135.250320] CPU: 2 PID: 238 Comm: tmp118 Not tainted 5.19.0-rc8+ #4 [ 135.252067] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014 [ 135.255065] RIP: 0010:ext4_ext_map_blocks+0xc20/0xcb0 [ 135.256475] Code: [ 135.261433] RSP: 0018:ffffc900005939f8 EFLAGS: 00010246 [ 135.262847] RAX: 0000000000000024 RBX: ffffc90000593b70 RCX: 0000000000000023 [ 135.264765] RDX: ffff8880038e5f10 RSI: 0000000000000003 RDI: ffff8880046e922c [ 135.266670] RBP: ffff8880046e9348 R08: 0000000000000001 R09: ffff888002ca580c [ 135.268576] R10: 0000000000002602 R11: 0000000000000000 R12: 0000000000000024 [ 135.270477] R13: 0000000000000000 R14: 0000000000000024 R15: 0000000000000000 [ 135.272394] FS: 00007fdabdc56740(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000 [ 135.274510] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 135.276075] CR2: 00007ffc26bd4f00 CR3: 0000000006261004 CR4: 0000000000170ea0 [ 135.277952] Call Trace: [ 135.278635] [ 135.279247] ? preempt_count_add+0x6d/0xa0 [ 135.280358] ? percpu_counter_add_batch+0x55/0xb0 [ 135.281612] ? _raw_read_unlock+0x18/0x30 [ 135.282704] ext4_map_blocks+0x294/0x5a0 [ 135.283745] ? xa_load+0x6f/0xa0 [ 135.284562] ext4_mpage_readpages+0x3d6/0x770 [ 135.285646] read_pages+0x67/0x1d0 [ 135.286492] ? folio_add_lru+0x51/0x80 [ 135.287441] page_cache_ra_unbounded+0x124/0x170 [ 135.288510] filemap_get_pages+0x23d/0x5a0 [ 135.289457] ? path_openat+0xa72/0xdd0 [ 135.290332] filemap_read+0xbf/0x300 [ 135.291158] ? _raw_spin_lock_irqsave+0x17/0x40 [ 135.292192] new_sync_read+0x103/0x170 [ 135.293014] vfs_read+0x15d/0x180 [ 135.293745] ksys_read+0xa1/0xe0 [ 135.294461] do_syscall_64+0x3c/0x80 [ 135.295284] entry_SYSCALL_64_after_hwframe+0x46/0xb0 This patch simply adds an extra check in __ext4_ext_check(), verifying that eh_entries is not 0 when eh_depth is > 0. Link: https://bugzilla.kernel.org/show_bug.cgi?id=215941 Link: https://bugzilla.kernel.org/show_bug.cgi?id=216283 Cc: Baokun Li Cc: stable@kernel.org Signed-off-by: Luís Henriques Reviewed-by: Jan Kara Reviewed-by: Baokun Li Link: https://lore.kernel.org/r/20220822094235.2690-1-lhenriques@suse.de Signed-off-by: Theodore Ts'o

ext4: fix bug_on in __es_tree_search

2022-05-24T19:34:17+00:00

Hulk Robot reported a BUG_ON: ================================================================== kernel BUG at fs/ext4/extents_status.c:199! [...] RIP: 0010:ext4_es_end fs/ext4/extents_status.c:199 [inline] RIP: 0010:__es_tree_search+0x1e0/0x260 fs/ext4/extents_status.c:217 [...] Call Trace: ext4_es_cache_extent+0x109/0x340 fs/ext4/extents_status.c:766 ext4_cache_extents+0x239/0x2e0 fs/ext4/extents.c:561 ext4_find_extent+0x6b7/0xa20 fs/ext4/extents.c:964 ext4_ext_map_blocks+0x16b/0x4b70 fs/ext4/extents.c:4384 ext4_map_blocks+0xe26/0x19f0 fs/ext4/inode.c:567 ext4_getblk+0x320/0x4c0 fs/ext4/inode.c:980 ext4_bread+0x2d/0x170 fs/ext4/inode.c:1031 ext4_quota_read+0x248/0x320 fs/ext4/super.c:6257 v2_read_header+0x78/0x110 fs/quota/quota_v2.c:63 v2_check_quota_file+0x76/0x230 fs/quota/quota_v2.c:82 vfs_load_quota_inode+0x5d1/0x1530 fs/quota/dquot.c:2368 dquot_enable+0x28a/0x330 fs/quota/dquot.c:2490 ext4_quota_enable fs/ext4/super.c:6137 [inline] ext4_enable_quotas+0x5d7/0x960 fs/ext4/super.c:6163 ext4_fill_super+0xa7c9/0xdc00 fs/ext4/super.c:4754 mount_bdev+0x2e9/0x3b0 fs/super.c:1158 mount_fs+0x4b/0x1e4 fs/super.c:1261 [...] ================================================================== Above issue may happen as follows: ------------------------------------- ext4_fill_super ext4_enable_quotas ext4_quota_enable ext4_iget __ext4_iget ext4_ext_check_inode ext4_ext_check __ext4_ext_check ext4_valid_extent_entries Check for overlapping extents does't take effect dquot_enable vfs_load_quota_inode v2_check_quota_file v2_read_header ext4_quota_read ext4_bread ext4_getblk ext4_map_blocks ext4_ext_map_blocks ext4_find_extent ext4_cache_extents ext4_es_cache_extent ext4_es_cache_extent __es_tree_search ext4_es_end BUG_ON(es->es_lblk + es->es_len < es->es_lblk) The error ext4 extents is as follows: 0af3 0300 0400 0000 00000000 extent_header 00000000 0100 0000 12000000 extent1 00000000 0100 0000 18000000 extent2 02000000 0400 0000 14000000 extent3 In the ext4_valid_extent_entries function, if prev is 0, no error is returned even if lblock<=prev. This was intended to skip the check on the first extent, but in the error image above, prev=0+1-1=0 when checking the second extent, so even though lblock<=prev, the function does not return an error. As a result, bug_ON occurs in __es_tree_search and the system panics. To solve this problem, we only need to check that: 1. The lblock of the first extent is not less than 0. 2. The lblock of the next extent is not less than the next block of the previous extent. The same applies to extent_idx. Cc: stable@kernel.org Fixes: 5946d089379a ("ext4: check for overlapping extents in ext4_valid_extent_entries()") Reported-by: Hulk Robot Signed-off-by: Baokun Li Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220518120816.1541863-1-libaokun1@huawei.com Signed-off-by: Theodore Ts'o

ext4: fix race condition between ext4_write and ext4_convert_inline_data

2022-05-17T18:17:40+00:00

Hulk Robot reported a BUG_ON: ================================================================== EXT4-fs error (device loop3): ext4_mb_generate_buddy:805: group 0, block bitmap and bg descriptor inconsistent: 25 vs 31513 free clusters kernel BUG at fs/ext4/ext4_jbd2.c:53! invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 0 PID: 25371 Comm: syz-executor.3 Not tainted 5.10.0+ #1 RIP: 0010:ext4_put_nojournal fs/ext4/ext4_jbd2.c:53 [inline] RIP: 0010:__ext4_journal_stop+0x10e/0x110 fs/ext4/ext4_jbd2.c:116 [...] Call Trace: ext4_write_inline_data_end+0x59a/0x730 fs/ext4/inline.c:795 generic_perform_write+0x279/0x3c0 mm/filemap.c:3344 ext4_buffered_write_iter+0x2e3/0x3d0 fs/ext4/file.c:270 ext4_file_write_iter+0x30a/0x11c0 fs/ext4/file.c:520 do_iter_readv_writev+0x339/0x3c0 fs/read_write.c:732 do_iter_write+0x107/0x430 fs/read_write.c:861 vfs_writev fs/read_write.c:934 [inline] do_pwritev+0x1e5/0x380 fs/read_write.c:1031 [...] ================================================================== Above issue may happen as follows: cpu1 cpu2 __________________________|__________________________ do_pwritev vfs_writev do_iter_write ext4_file_write_iter ext4_buffered_write_iter generic_perform_write ext4_da_write_begin vfs_fallocate ext4_fallocate ext4_convert_inline_data ext4_convert_inline_data_nolock ext4_destroy_inline_data_nolock clear EXT4_STATE_MAY_INLINE_DATA ext4_map_blocks ext4_ext_map_blocks ext4_mb_new_blocks ext4_mb_regular_allocator ext4_mb_good_group_nolock ext4_mb_init_group ext4_mb_init_cache ext4_mb_generate_buddy --> error ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) ext4_restore_inline_data set EXT4_STATE_MAY_INLINE_DATA ext4_block_write_begin ext4_da_write_end ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) ext4_write_inline_data_end handle=NULL ext4_journal_stop(handle) __ext4_journal_stop ext4_put_nojournal(handle) ref_cnt = (unsigned long)handle BUG_ON(ref_cnt == 0) ---> BUG_ON The lock held by ext4_convert_inline_data is xattr_sem, but the lock held by generic_perform_write is i_rwsem. Therefore, the two locks can be concurrent. To solve above issue, we add inode_lock() for ext4_convert_inline_data(). At the same time, move ext4_convert_inline_data() in front of ext4_punch_hole(), remove similar handling from ext4_punch_hole(). Fixes: 0c8d414f163f ("ext4: let fallocate handle inline data correctly") Cc: stable@vger.kernel.org Reported-by: Hulk Robot Signed-off-by: Baokun Li Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220428134031.4153381-1-libaokun1@huawei.com Signed-off-by: Theodore Ts'o

ext4: fix fallocate to use file_modified to update permissions consistently

2022-04-13T02:22:02+00:00

Since the initial introduction of (posix) fallocate back at the turn of the century, it has been possible to use this syscall to change the user-visible contents of files. This can happen by extending the file size during a preallocation, or through any of the newer modes (punch, zero, collapse, insert range). Because the call can be used to change file contents, we should treat it like we do any other modification to a file -- update the mtime, and drop set[ug]id privileges/capabilities. The VFS function file_modified() does all this for us if pass it a locked inode, so let's make fallocate drop permissions correctly. Signed-off-by: Darrick J. Wong Link: https://lore.kernel.org/r/20220308185043.GA117678@magnolia Signed-off-by: Theodore Ts'o Cc: stable@kernel.org

ext4: remove redundant assignment to variable split_flag1

2022-03-03T05:01:31+00:00

Variable split_flag1 is being assigned a value that is never read, it is being re-assigned a new value in the following code block. The assignment is redundant and can be removed. Cleans up clang scan build warning: fs/ext4/extents.c:3371:2: warning: Value stored to 'split_flag1' is never read [deadcode.DeadStores] Signed-off-by: Colin Ian King Link: https://lore.kernel.org/r/20220301121644.997833-1-colin.i.king@gmail.com Signed-off-by: Theodore Ts'o

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

2022-02-06T18:34:45+00:00

Pull ext4 fixes from Ted Ts'o: "Various bug fixes for ext4 fast commit and inline data handling. Also fix regression introduced as part of moving to the new mount API" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: fs/ext4: fix comments mentioning i_mutex ext4: fix incorrect type issue during replay_del_range jbd2: fix kernel-doc descriptions for jbd2_journal_shrink_{scan,count}() ext4: fix potential NULL pointer dereference in ext4_fill_super() jbd2: refactor wait logic for transaction updates into a common function jbd2: cleanup unused functions declarations from jbd2.h ext4: fix error handling in ext4_fc_record_modified_inode() ext4: remove redundant max inline_size check in ext4_da_write_inline_data_begin() ext4: fix error handling in ext4_restore_inline_data() ext4: fast commit may miss file actions ext4: fast commit may not fallback for ineligible commit ext4: modify the logic of ext4_mb_new_blocks_simple ext4: prevent used blocks from being allocated during fast commit replay

fs/ext4: fix comments mentioning i_mutex

2022-02-03T15:57:53+00:00

inode->i_mutex has been replaced with inode->i_rwsem long ago. Fix comments still mentioning i_mutex. Signed-off-by: hongnanli Link: https://lore.kernel.org/r/20220121070611.21618-1-hongnan.li@linux.alibaba.com Signed-off-by: Theodore Ts'o

ext4: fast commit may not fallback for ineligible commit

2022-02-03T15:56:39+00:00

For the follow scenario: 1. jbd start commit transaction n 2. task A get new handle for transaction n+1 3. task A do some ineligible actions and mark FC_INELIGIBLE 4. jbd complete transaction n and clean FC_INELIGIBLE 5. task A call fsync In this case fast commit will not fallback to full commit and transaction n+1 also not handled by jbd. Make ext4_fc_mark_ineligible() also record transaction tid for latest ineligible case, when call ext4_fc_cleanup() check current transaction tid, if small than latest ineligible tid do not clear the EXT4_MF_FC_INELIGIBLE. Reported-by: kernel test robot Reported-by: Dan Carpenter Reported-by: Ritesh Harjani Suggested-by: Harshad Shirwadkar Signed-off-by: Xin Yin Link: https://lore.kernel.org/r/20220117093655.35160-2-yinxin.x@bytedance.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org