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

erofs: fix the out-of-bounds nameoff handling for trailing dirents

2026-04-21T08:56:04+00:00

Currently we already have boundary-checks for nameoffs, but the trailing dirents are special since the namelens are calculated with strnlen() with unchecked nameoffs. If a crafted EROFS has a trailing dirent with nameoff >= maxsize, maxsize - nameoff can underflow, causing strnlen() to read past the directory block. nameoff0 should also be verified to be a multiple of `sizeof(struct erofs_dirent)` as well [1]. [1] https://sashiko.dev/#/patchset/20260416063511.3173774-1-hsiangkao%40linux.alibaba.com Fixes: 3aa8ec716e52 ("staging: erofs: add directory operations") Fixes: 33bac912840f ("staging: erofs: keep corrupted fs from crashing kernel in erofs_readdir()") Reported-by: Yuhao Jiang Reported-by: Junrui Luo Closes: https://lore.kernel.org/r/A0FD7E0F-7558-49B0-8BC8-EB1ECDB2479A@outlook.com Cc: stable@vger.kernel.org Signed-off-by: Gao Xiang Reviewed-by: Chao Yu

erofs: add setlease file operation

2026-01-12T09:55:45+00:00

Add the setlease file_operation to erofs_file_fops and erofs_dir_fops, 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-v1-4-ea4dec9b67fa@kernel.org Acked-by: Al Viro Acked-by: Christoph Hellwig Reviewed-by: Chao Yu Signed-off-by: Christian Brauner

erofs: Add support for FS_IOC_GETFSLABEL

2025-09-25T03:26:20+00:00

Add support for reading to the erofs volume label from the FS_IOC_GETFSLABEL ioctls. Signed-off-by: Bo Liu (OpenAnolis) Reviewed-by: Gao Xiang Reviewed-by: Chao Yu Reviewed-by: Hongbo Li Signed-off-by: Gao Xiang

erofs: support to readahead dirent blocks in erofs_readdir()

2025-07-24T11:44:08+00:00

This patch supports to readahead more blocks in erofs_readdir(), it can enhance readdir performance in large direcotry. readdir test in a large directory which contains 12000 sub-files. files_per_second Before: 926385.54 After: 2380435.562 Meanwhile, let's introduces a new sysfs entry to control readahead bytes to provide more flexible policy for readahead of readdir(). - location: /sys/fs/erofs//dir_ra_bytes - default value: 16384 - disable readahead: set the value to 0 Signed-off-by: Chao Yu Reviewed-by: Gao Xiang Link: https://lore.kernel.org/r/20250721021352.2495371-1-chao@kernel.org [ Gao Xiang: minor styling adjustment. ] Signed-off-by: Gao Xiang

erofs: implement metadata compression

2025-07-24T11:43:31+00:00

Thanks to the meta buffer infrastructure, metadata-compressed inodes are just read from the metabox inode instead of the blockdevice (or backing file) inode. The same is true for shared extended attributes. When metadata compression is enabled, inode numbers are divided from on-disk NIDs because of non-LTS 32-bit application compatibility. Co-developed-by: Gao Xiang Signed-off-by: Bo Liu (OpenAnolis) Acked-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20250722003229.2121752-1-hsiangkao@linux.alibaba.com

erofs: allow readdir() to be interrupted

2025-07-10T09:08:27+00:00

In a quick slow device, readdir() may loop for long time in large directory, let's give a chance to allow it to be interrupted by userspace. Signed-off-by: Chao Yu Reviewed-by: Gao Xiang Link: https://lore.kernel.org/r/20250710073619.4083422-1-chao@kernel.org [ Gao Xiang: move cond_resched() to the end of the while loop. ] Signed-off-by: Gao Xiang

erofs: support dot-omitted directories

2025-03-16T17:25:32+00:00

There's no need to record "." dirents in the directory data (while they could be used for sanity checks, they aren't very useful.) Omitting "." dirents also improves directory data deduplication. Use a per-inode (instead of per-sb) flag to indicate if the "." dirent is omitted or not, ensuring compatibility with incremental builds. It also reuses EROFS_I_NLINK_1_BIT, as it has very limited use cases for directories with `nlink = 1`. Emit the "." entry as the last virtual dirent in the directory because it is _much_ less frequently used than the ".." dirent. It also keeps `f_pos` meaningful, as it strictly follows the directory data when it's less than i_size. Signed-off-by: Gao Xiang Acked-by: Chao Yu Link: https://lore.kernel.org/r/20250310095459.2620647-6-hsiangkao@linux.alibaba.com

erofs: implement 48-bit block addressing for unencoded inodes

2025-03-16T17:25:26+00:00

It adapts the on-disk changes from the previous commit. It also supports EROFS_NULL_ADDR (all 1's) for EROFS_INODE_FLAT_PLAIN inodes to indicate 0-filled inodes, as it's common for composefs use cases. As a result, EROFS_INODE_CHUNK_BASED is no longer needed. Signed-off-by: Gao Xiang Acked-by: Chao Yu Link: https://lore.kernel.org/r/20250310095459.2620647-5-hsiangkao@linux.alibaba.com

erofs: get rid of erofs_kmap_type

2025-03-16T17:21:24+00:00

Since EROFS_KMAP_ATOMIC is no longer valid, get rid of erofs_kmap_type too. Signed-off-by: Bo Liu Reviewed-by: Gao Xiang Reviewed-by: Chao Yu Link: https://lore.kernel.org/r/20250217093141.2659-1-liubo03@inspur.com Signed-off-by: Gao Xiang

erofs: simplify readdir operation

2024-08-19T03:06:20+00:00

- Use i_size instead of i_size_read() due to immutable fses; - Get rid of an unneeded goto since erofs_fill_dentries() also works; - Remove unnecessary lines. Signed-off-by: Hongzhen Luo Link: https://lore.kernel.org/r/20240801112622.2164029-1-hongzhen@linux.alibaba.com Reviewed-by: Gao Xiang Signed-off-by: Gao Xiang