Unverified Commit 8637fa89 authored by Yongpeng Yang's avatar Yongpeng Yang Committed by Christian Brauner
Browse files

block: add __must_check attribute to sb_min_blocksize() 



When sb_min_blocksize() returns 0 and the return value is not checked,
it may lead to a situation where sb->s_blocksize is 0 when
accessing the filesystem super block. After commit a64e5a59
("bdev: add back PAGE_SIZE block size validation for
sb_set_blocksize()"), this becomes more likely to happen when the
block device’s logical_block_size is larger than PAGE_SIZE and the
filesystem is unformatted. Add the __must_check attribute to ensure
callers always check the return value.

Cc: stable@vger.kernel.org # v6.15
Suggested-by: default avatarMatthew Wilcox <willy@infradead.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarYongpeng Yang <yangyongpeng@xiaomi.com>
Link: https://patch.msgid.link/20251104125009.2111925-6-yangyongpeng.storage@gmail.com


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 124af086

block/bdev.c

+1 −1
Original line number Diff line number Diff line
@@ -231,7 +231,7 @@ int sb_set_blocksize(struct super_block *sb, int size) 


EXPORT_SYMBOL(sb_set_blocksize);



int sb_min_blocksize(struct super_block *sb, int size)

int __must_check sb_min_blocksize(struct super_block *sb, int size)

{

	int minsize = bdev_logical_block_size(sb->s_bdev);

	if (size < minsize)

include/linux/fs.h

+2 −2
Original line number Diff line number Diff line
@@ -3423,8 +3423,8 @@ static inline void remove_inode_hash(struct inode *inode) 
extern void inode_sb_list_add(struct inode *inode);

extern void inode_add_lru(struct inode *inode);



extern int sb_set_blocksize(struct super_block *, int);

extern int sb_min_blocksize(struct super_block *, int);

int sb_set_blocksize(struct super_block *sb, int size);

int __must_check sb_min_blocksize(struct super_block *sb, int size);



int generic_file_mmap(struct file *, struct vm_area_struct *);

int generic_file_mmap_prepare(struct vm_area_desc *desc);