kernel/linux.git/fs/sysv/itree.c, branch v6.12.80

buffer: Convert __block_write_begin() to take a folio

2024-08-07T09:33:36+00:00

Almost all callers have a folio now, so change __block_write_begin() to take a folio and remove a call to compound_head(). Reviewed-by: Josef Bacik Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Christian Brauner

fs: Convert aops->write_begin to take a folio

2024-08-07T09:33:21+00:00

Convert all callers from working on a page to working on one page of a folio (support for working on an entire folio can come later). Removes a lot of folio->page->folio conversions. Reviewed-by: Josef Bacik Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Christian Brauner

sysv: Convert sysv_prepare_chunk() to take a folio

2024-08-07T09:31:54+00:00

All callers now have a folio, so convert sysv_prepare_chunk() to take one. Reviewed-by: Josef Bacik Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Christian Brauner

sysv: don't call sb_bread() with pointers_lock held

2024-02-02T12:11:49+00:00

syzbot is reporting sleep in atomic context in SysV filesystem [1], for sb_bread() is called with rw_spinlock held. A "write_lock(&pointers_lock) => read_lock(&pointers_lock) deadlock" bug and a "sb_bread() with write_lock(&pointers_lock)" bug were introduced by "Replace BKL for chain locking with sysvfs-private rwlock" in Linux 2.5.12. Then, "[PATCH] err1-40: sysvfs locking fix" in Linux 2.6.8 fixed the former bug by moving pointers_lock lock to the callers, but instead introduced a "sb_bread() with read_lock(&pointers_lock)" bug (which made this problem easier to hit). Al Viro suggested that why not to do like get_branch()/get_block()/ find_shared() in Minix filesystem does. And doing like that is almost a revert of "[PATCH] err1-40: sysvfs locking fix" except that get_branch() from with find_shared() is called without write_lock(&pointers_lock). Reported-by: syzbot Link: https://syzkaller.appspot.com/bug?extid=69b40dc5fd40f32c199f Suggested-by: Al Viro Signed-off-by: Tetsuo Handa Link: https://lore.kernel.org/r/0d195f93-a22a-49a2-0020-103534d6f7f6@I-love.SAKURA.ne.jp Signed-off-by: Christian Brauner

sysv: remove writepage implementation

2023-12-29T19:58:35+00:00

If the filesystem implements migrate_folio and writepages, there is no need for a writepage implementation. Link: https://lkml.kernel.org/r/20231215200245.748418-12-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Jens Axboe Cc: Christoph Hellwig Signed-off-by: Andrew Morton

sysv: convert to new timestamp accessors

2023-10-18T12:08:28+00:00

Convert to using the new inode timestamp accessor functions. Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20231004185347.80880-69-jlayton@kernel.org Signed-off-by: Christian Brauner

fs: pass the request_mask to generic_fillattr

2023-08-09T06:56:36+00:00

generic_fillattr just fills in the entire stat struct indiscriminately today, copying data from the inode. There is at least one attribute (STATX_CHANGE_COOKIE) that can have side effects when it is reported, and we're looking at adding more with the addition of multigrain timestamps. Add a request_mask argument to generic_fillattr and have most callers just pass in the value that is passed to getattr. Have other callers (e.g. ksmbd) just pass in STATX_BASIC_STATS. Also move the setting of STATX_CHANGE_COOKIE into generic_fillattr. Acked-by: Joseph Qi Reviewed-by: Xiubo Li Reviewed-by: "Paulo Alcantara (SUSE)" Reviewed-by: Jan Kara Signed-off-by: Jeff Layton Message-Id: <20230807-mgctime-v7-2-d1dec143a704@kernel.org> Signed-off-by: Christian Brauner

sysv: convert to ctime accessor functions

2023-07-24T08:30:05+00:00

In later patches, we're going to change how the inode's ctime field is used. Switch to using accessor functions instead of raw accesses of inode->i_ctime. Signed-off-by: Jeff Layton Reviewed-by: Jan Kara Message-Id: <20230705190309.579783-74-jlayton@kernel.org> Signed-off-by: Christian Brauner

fs/sysv: Null check to prevent null-ptr-deref bug

2023-06-01T07:51:06+00:00

sb_getblk(inode->i_sb, parent) return a null ptr and taking lock on that leads to the null-ptr-deref bug. Reported-by: syzbot+aad58150cbc64ba41bdc@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=aad58150cbc64ba41bdc Signed-off-by: Prince Kumar Maurya Message-Id: <20230531013141.19487-1-princekumarmaurya06@gmail.com> Signed-off-by: Christian Brauner

fs: port ->getattr() to pass mnt_idmap

2023-01-19T08:24:25+00:00

Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner (Microsoft)