kernel/linux.git/fs/erofs, branch v6.2.2

erofs: clean up parsing of fscache related options

2023-01-16T14:39:47+00:00

... to avoid the mess of conditional preprocessing as we are continually adding fscache related mount options. Reviewd-by: Gao Xiang Reviewed-by: Yue Hu Reviewed-by: Chao Yu Signed-off-by: Jingbo Xu Link: https://lore.kernel.org/r/20230112065431.124926-3-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang

erofs: fix kvcalloc() misuse with __GFP_NOFAIL

2023-01-10T08:41:45+00:00

As reported by syzbot [1], kvcalloc() cannot work with __GFP_NOFAIL. Let's use kcalloc() instead. [1] https://lore.kernel.org/r/0000000000007796bd05f1852ec2@google.com Reported-by: syzbot+c3729cda01706a04fb98@syzkaller.appspotmail.com Fixes: fe3e5914e6dc ("erofs: try to leave (de)compressed_pages on stack if possible") Fixes: 4f05687fd703 ("erofs: introduce struct z_erofs_decompress_backend") Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20230110074927.41651-1-hsiangkao@linux.alibaba.com

erofs/zmap.c: Fix incorrect offset calculation

2023-01-10T08:38:53+00:00

Effective offset to add to length was being incorrectly calculated, which resulted in iomap->length being set to 0, triggering a WARN_ON in iomap_iter_done(). Fix that, and describe it in comments. This was reported as a crash by syzbot under an issue about a warning encountered in iomap_iter_done(), but unrelated to erofs. C reproducer: https://syzkaller.appspot.com/text?tag=ReproC&x=1037a6b2880000 Kernel config: https://syzkaller.appspot.com/text?tag=KernelConfig&x=e2021a61197ebe02 Dashboard link: https://syzkaller.appspot.com/bug?extid=a8e049cd3abd342936b6 Reported-by: syzbot+a8e049cd3abd342936b6@syzkaller.appspotmail.com Suggested-by: Gao Xiang Signed-off-by: Siddh Raman Pant Reviewed-by: Gao Xiang Reviewed-by: Chao Yu Link: https://lore.kernel.org/r/20221209102151.311049-1-code@siddh.me Signed-off-by: Gao Xiang

Merge tag 'erofs-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs

2022-12-13T04:14:04+00:00

Pull erofs updates from Gao Xiang: "In this cycle, large folios are now enabled in the iomap/fscache mode for uncompressed files first. In order to do that, we've also cleaned up better interfaces between erofs and fscache, which are acked by fscache/netfs folks and included in this pull request. Other than that, there are random fixes around erofs over fscache and crafted images by syzbot, minor cleanups and documentation updates. Summary: - Enable large folios for iomap/fscache mode - Avoid sysfs warning due to mounting twice with the same fsid and domain_id in fscache mode - Refine fscache interface among erofs, fscache, and cachefiles - Use kmap_local_page() only for metabuf - Fixes around crafted images found by syzbot - Minor cleanups and documentation updates" * tag 'erofs-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: validate the extent length for uncompressed pclusters erofs: fix missing unmap if z_erofs_get_extent_compressedlen() fails erofs: Fix pcluster memleak when its block address is zero erofs: use kmap_local_page() only for erofs_bread() erofs: enable large folios for fscache mode erofs: support large folios for fscache mode erofs: switch to prepare_ondemand_read() in fscache mode fscache,cachefiles: add prepare_ondemand_read() callback erofs: clean up cached I/O strategies erofs: update documentation erofs: check the uniqueness of fsid in shared domain in advance erofs: enable large folios for iomap mode

Merge tag 'fs.acl.rework.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping

2022-12-13T02:46:39+00:00

Pull VFS acl updates from Christian Brauner: "This contains the work that builds a dedicated vfs posix acl api. The origins of this work trace back to v5.19 but it took quite a while to understand the various filesystem specific implementations in sufficient detail and also come up with an acceptable solution. As we discussed and seen multiple times the current state of how posix acls are handled isn't nice and comes with a lot of problems: The current way of handling posix acls via the generic xattr api is error prone, hard to maintain, and type unsafe for the vfs until we call into the filesystem's dedicated get and set inode operations. It is already the case that posix acls are special-cased to death all the way through the vfs. There are an uncounted number of hacks that operate on the uapi posix acl struct instead of the dedicated vfs struct posix_acl. And the vfs must be involved in order to interpret and fixup posix acls before storing them to the backing store, caching them, reporting them to userspace, or for permission checking. Currently a range of hacks and duct tape exist to make this work. As with most things this is really no ones fault it's just something that happened over time. But the code is hard to understand and difficult to maintain and one is constantly at risk of introducing bugs and regressions when having to touch it. Instead of continuing to hack posix acls through the xattr handlers this series builds a dedicated posix acl api solely around the get and set inode operations. Going forward, the vfs_get_acl(), vfs_remove_acl(), and vfs_set_acl() helpers must be used in order to interact with posix acls. They operate directly on the vfs internal struct posix_acl instead of abusing the uapi posix acl struct as we currently do. In the end this removes all of the hackiness, makes the codepaths easier to maintain, and gets us type safety. This series passes the LTP and xfstests suites without any regressions. For xfstests the following combinations were tested: - xfs - ext4 - btrfs - overlayfs - overlayfs on top of idmapped mounts - orangefs - (limited) cifs There's more simplifications for posix acls that we can make in the future if the basic api has made it. A few implementation details: - The series makes sure to retain exactly the same security and integrity module permission checks. Especially for the integrity modules this api is a win because right now they convert the uapi posix acl struct passed to them via a void pointer into the vfs struct posix_acl format to perform permission checking on the mode. There's a new dedicated security hook for setting posix acls which passes the vfs struct posix_acl not a void pointer. Basing checking on the posix acl stored in the uapi format is really unreliable. The vfs currently hacks around directly in the uapi struct storing values that frankly the security and integrity modules can't correctly interpret as evidenced by bugs we reported and fixed in this area. It's not necessarily even their fault it's just that the format we provide to them is sub optimal. - Some filesystems like 9p and cifs need access to the dentry in order to get and set posix acls which is why they either only partially or not even at all implement get and set inode operations. For example, cifs allows setxattr() and getxattr() operations but doesn't allow permission checking based on posix acls because it can't implement a get acl inode operation. Thus, this patch series updates the set acl inode operation to take a dentry instead of an inode argument. However, for the get acl inode operation we can't do this as the old get acl method is called in e.g., generic_permission() and inode_permission(). These helpers in turn are called in various filesystem's permission inode operation. So passing a dentry argument to the old get acl inode operation would amount to passing a dentry to the permission inode operation which we shouldn't and probably can't do. So instead of extending the existing inode operation Christoph suggested to add a new one. He also requested to ensure that the get and set acl inode operation taking a dentry are consistently named. So for this version the old get acl operation is renamed to ->get_inode_acl() and a new ->get_acl() inode operation taking a dentry is added. With this we can give both 9p and cifs get and set acl inode operations and in turn remove their complex custom posix xattr handlers. In the future I hope to get rid of the inode method duplication but it isn't like we have never had this situation. Readdir is just one example. And frankly, the overall gain in type safety and the more pleasant api wise are simply too big of a benefit to not accept this duplication for a while. - We've done a full audit of every codepaths using variant of the current generic xattr api to get and set posix acls and surprisingly it isn't that many places. There's of course always a chance that we might have missed some and if so I'm sure we'll find them soon enough. The crucial codepaths to be converted are obviously stacking filesystems such as ecryptfs and overlayfs. For a list of all callers currently using generic xattr api helpers see [2] including comments whether they support posix acls or not. - The old vfs generic posix acl infrastructure doesn't obey the create and replace semantics promised on the setxattr(2) manpage. This patch series doesn't address this. It really is something we should revisit later though. The patches are roughly organized as follows: (1) Change existing set acl inode operation to take a dentry argument (Intended to be a non-functional change) (2) Rename existing get acl method (Intended to be a non-functional change) (3) Implement get and set acl inode operations for filesystems that couldn't implement one before because of the missing dentry. That's mostly 9p and cifs (Intended to be a non-functional change) (4) Build posix acl api, i.e., add vfs_get_acl(), vfs_remove_acl(), and vfs_set_acl() including security and integrity hooks (Intended to be a non-functional change) (5) Implement get and set acl inode operations for stacking filesystems (Intended to be a non-functional change) (6) Switch posix acl handling in stacking filesystems to new posix acl api now that all filesystems it can stack upon support it. (7) Switch vfs to new posix acl api (semantical change) (8) Remove all now unused helpers (9) Additional regression fixes reported after we merged this into linux-next Thanks to Seth for a lot of good discussion around this and encouragement and input from Christoph" * tag 'fs.acl.rework.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping: (36 commits) posix_acl: Fix the type of sentinel in get_acl orangefs: fix mode handling ovl: call posix_acl_release() after error checking evm: remove dead code in evm_inode_set_acl() cifs: check whether acl is valid early acl: make vfs_posix_acl_to_xattr() static acl: remove a slew of now unused helpers 9p: use stub posix acl handlers cifs: use stub posix acl handlers ovl: use stub posix acl handlers ecryptfs: use stub posix acl handlers evm: remove evm_xattr_acl_change() xattr: use posix acl api ovl: use posix acl api ovl: implement set acl method ovl: implement get acl method ecryptfs: implement set acl method ecryptfs: implement get acl method ksmbd: use vfs_remove_acl() acl: add vfs_remove_acl() ...

erofs: validate the extent length for uncompressed pclusters

2022-12-07T02:56:31+00:00

syzkaller reported a KASAN use-after-free: https://syzkaller.appspot.com/bug?extid=2ae90e873e97f1faf6f2 The referenced fuzzed image actually has two issues: - m_pa == 0 as a non-inlined pcluster; - The logical length is longer than its physical length. The first issue has already been addressed. This patch addresses the second issue by checking the extent length validity. Reported-by: syzbot+2ae90e873e97f1faf6f2@syzkaller.appspotmail.com Fixes: 02827e1796b3 ("staging: erofs: add erofs_map_blocks_iter") Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20221205150050.47784-2-hsiangkao@linux.alibaba.com

erofs: fix missing unmap if z_erofs_get_extent_compressedlen() fails

2022-12-07T02:56:31+00:00

Otherwise, meta buffers could be leaked. Fixes: cec6e93beadf ("erofs: support parsing big pcluster compress indexes") Reviewed-by: Yue Hu Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20221205150050.47784-1-hsiangkao@linux.alibaba.com

erofs: Fix pcluster memleak when its block address is zero

2022-12-07T02:56:31+00:00

syzkaller reported a memleak: https://syzkaller.appspot.com/bug?id=62f37ff612f0021641eda5b17f056f1668aa9aed unreferenced object 0xffff88811009c7f8 (size 136): ... backtrace: [] z_erofs_do_read_page+0x99b/0x1740 [] z_erofs_readahead+0x24e/0x580 [] read_pages+0x86/0x3d0 ... syzkaller constructed a case: in z_erofs_register_pcluster(), ztailpacking = false and map->m_pa = zero. This makes pcl->obj.index be zero although pcl is not a inline pcluster. Then following path adds refcount for grp, but the refcount won't be put because pcl is inline. z_erofs_readahead() z_erofs_do_read_page() # for another page z_erofs_collector_begin() erofs_find_workgroup() erofs_workgroup_get() Since it's illegal for the block address of a non-inlined pcluster to be zero, add check here to avoid registering the pcluster which would be leaked. Fixes: cecf864d3d76 ("erofs: support inline data decompression") Reported-by: syzbot+6f8cd9a0155b366d227f@syzkaller.appspotmail.com Signed-off-by: Chen Zhongjin Reviewed-by: Yue Hu Reviewed-by: Gao Xiang Reviewed-by: Chao Yu Link: https://lore.kernel.org/r/Y42Kz6sVkf+XqJRB@debian Signed-off-by: Gao Xiang

erofs: use kmap_local_page() only for erofs_bread()

2022-12-07T02:56:31+00:00

Convert all mapped erofs_bread() users to use kmap_local_page() instead of kmap() or kmap_atomic(). Signed-off-by: Gao Xiang Reviewed-and-tested-by: Jingbo Xu Reviewed-by: Chao Yu Link: https://lore.kernel.org/r/20221018105313.4940-1-hsiangkao@linux.alibaba.com Signed-off-by: Gao Xiang

erofs: enable large folios for fscache mode

2022-12-07T02:56:31+00:00

Enable large folios for fscache mode. Enable this feature for non-compressed format for now, until the compression part supports large folios later. One thing worth noting is that, the feature is not enabled for the meta data routine since meta inodes don't need large folios for now, nor do they support readahead yet. Also document this new feature. Signed-off-by: Jingbo Xu Reviewed-by: Jia Zhu Link: https://lore.kernel.org/r/20221201074256.16639-3-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang