kernel/linux.git/fs/ext4/namei.c, branch v6.1

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

ext4: fix BUG_ON() when directory entry has invalid rec_len

2022-11-06T05:07:49+00:00

The rec_len field in the directory entry has to be a multiple of 4. A corrupted filesystem image can be used to hit a BUG() in ext4_rec_len_to_disk(), called from make_indexed_dir(). ------------[ cut here ]------------ kernel BUG at fs/ext4/ext4.h:2413! ... RIP: 0010:make_indexed_dir+0x53f/0x5f0 ... Call Trace: ? add_dirent_to_buf+0x1b2/0x200 ext4_add_entry+0x36e/0x480 ext4_add_nondir+0x2b/0xc0 ext4_create+0x163/0x200 path_openat+0x635/0xe90 do_filp_open+0xb4/0x160 ? __create_object.isra.0+0x1de/0x3b0 ? _raw_spin_unlock+0x12/0x30 do_sys_openat2+0x91/0x150 __x64_sys_open+0x6c/0xa0 do_syscall_64+0x3c/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 The fix simply adds a call to ext4_check_dir_entry() to validate the directory entry, returning -EFSCORRUPTED if the entry is invalid. CC: stable@kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=216540 Signed-off-by: Luís Henriques Link: https://lore.kernel.org/r/20221012131330.32456-1-lhenriques@suse.de Signed-off-by: Theodore Ts'o

Merge tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2022-10-11T02:45:17+00:00

Pull vfs tmpfile updates from Al Viro: "Miklos' ->tmpfile() signature change; pass an unopened struct file to it, let it open the damn thing. Allows to add tmpfile support to FUSE" * tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fuse: implement ->tmpfile() vfs: open inside ->tmpfile() vfs: move open right after ->tmpfile() vfs: make vfs_tmpfile() static ovl: use vfs_tmpfile_open() helper cachefiles: use vfs_tmpfile_open() helper cachefiles: only pass inode to *mark_inode_inuse() helpers cachefiles: tmpfile error handling cleanup hugetlbfs: cleanup mknod and tmpfile vfs: add vfs_tmpfile_open() helper

ext4: fix dir corruption when ext4_dx_add_entry() fails

2022-10-01T03:46:52+00:00

Following process may lead to fs corruption: 1. ext4_create(dir/foo) ext4_add_nondir ext4_add_entry ext4_dx_add_entry a. add_dirent_to_buf ext4_mark_inode_dirty ext4_handle_dirty_metadata // dir inode bh is recorded into journal b. ext4_append // dx_get_count(entries) == dx_get_limit(entries) ext4_bread(EXT4_GET_BLOCKS_CREATE) ext4_getblk ext4_map_blocks ext4_ext_map_blocks ext4_mb_new_blocks dquot_alloc_block dquot_alloc_space_nodirty inode_add_bytes // update dir's i_blocks ext4_ext_insert_extent ext4_ext_dirty // record extent bh into journal ext4_handle_dirty_metadata(bh) // record new block into journal inode->i_size += inode->i_sb->s_blocksize // new size(in mem) c. ext4_handle_dirty_dx_node(bh2) // record dir's new block(dx_node) into journal d. ext4_handle_dirty_dx_node((frame - 1)->bh) e. ext4_handle_dirty_dx_node(frame->bh) f. do_split // ret err! g. add_dirent_to_buf ext4_mark_inode_dirty(dir) // update raw_inode on disk(skipped) 2. fsck -a /dev/sdb drop last block(dx_node) which beyonds dir's i_size. /dev/sdb: recovering journal /dev/sdb contains a file system with errors, check forced. /dev/sdb: Inode 12, end of extent exceeds allowed value (logical block 128, physical block 3938, len 1) 3. fsck -fn /dev/sdb dx_node->entry[i].blk > dir->i_size Pass 2: Checking directory structure Problem in HTREE directory inode 12 (/dir): bad block number 128. Clear HTree index? no Problem in HTREE directory inode 12: block #3 has invalid depth (2) Problem in HTREE directory inode 12: block #3 has bad max hash Problem in HTREE directory inode 12: block #3 not referenced Fix it by marking inode dirty directly inside ext4_append(). Fetch a reproducer in [Link]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=216466 Cc: stable@vger.kernel.org Signed-off-by: Zhihao Cheng Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220911045204.516460-1-chengzhihao1@huawei.com Signed-off-by: Theodore Ts'o

ext4: fix check for block being out of directory size

2022-09-30T03:01:40+00:00

The check in __ext4_read_dirblock() for block being outside of directory size was wrong because it compared block number against directory size in bytes. Fix it. Fixes: 65f8ea4cd57d ("ext4: check if directory block is within i_size") CVE: CVE-2022-1184 CC: stable@vger.kernel.org Signed-off-by: Jan Kara Reviewed-by: Lukas Czerner Link: https://lore.kernel.org/r/20220822114832.1482-1-jack@suse.cz Signed-off-by: Theodore Ts'o

vfs: open inside ->tmpfile()

2022-09-24T05:00:00+00:00

This is in preparation for adding tmpfile support to fuse, which requires that the tmpfile creation and opening are done as a single operation. Replace the 'struct dentry *' argument of i_op->tmpfile with 'struct file *'. Call finish_open_simple() as the last thing in ->tmpfile() instances (may be omitted in the error case). Change d_tmpfile() argument to 'struct file *' as well to make callers more readable. Reviewed-by: Christian Brauner (Microsoft) Signed-off-by: Miklos Szeredi

ext4: make sure ext4_append() always allocates new block

2022-08-03T03:56:17+00:00

ext4_append() must always allocate a new block, otherwise we run the risk of overwriting existing directory block corrupting the directory tree in the process resulting in all manner of problems later on. Add a sanity check to see if the logical block is already allocated and error out if it is. Cc: stable@kernel.org Signed-off-by: Lukas Czerner Reviewed-by: Andreas Dilger Link: https://lore.kernel.org/r/20220704142721.157985-2-lczerner@redhat.com Signed-off-by: Theodore Ts'o

ext4: check if directory block is within i_size

2022-08-03T03:56:17+00:00

Currently ext4 directory handling code implicitly assumes that the directory blocks are always within the i_size. In fact ext4_append() will attempt to allocate next directory block based solely on i_size and the i_size is then appropriately increased after a successful allocation. However, for this to work it requires i_size to be correct. If, for any reason, the directory inode i_size is corrupted in a way that the directory tree refers to a valid directory block past i_size, we could end up corrupting parts of the directory tree structure by overwriting already used directory blocks when modifying the directory. Fix it by catching the corruption early in __ext4_read_dirblock(). Addresses Red-Hat-Bugzilla: #2070205 CVE: CVE-2022-1184 Signed-off-by: Lukas Czerner Cc: stable@vger.kernel.org Reviewed-by: Andreas Dilger Link: https://lore.kernel.org/r/20220704142721.157985-1-lczerner@redhat.com Signed-off-by: Theodore Ts'o

ext4: avoid remove directory when directory is corrupted

2022-08-03T03:56:17+00:00

Now if check directoy entry is corrupted, ext4_empty_dir may return true then directory will be removed when file system mounted with "errors=continue". In order not to make things worse just return false when directory is corrupted. Signed-off-by: Ye Bin Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220622090223.682234-1-yebin10@huawei.com Signed-off-by: Theodore Ts'o

ext4: make variable "count" signed

2022-06-18T23:35:57+00:00

Since dx_make_map() may return -EFSCORRUPTED now, so change "count" to be a signed integer so we can correctly check for an error code returned by dx_make_map(). Fixes: 46c116b920eb ("ext4: verify dir block before splitting it") Cc: stable@kernel.org Signed-off-by: Ding Xiang Link: https://lore.kernel.org/r/20220530100047.537598-1-dingxiang@cmss.chinamobile.com Signed-off-by: Theodore Ts'o