Unverified Commit 25050181 authored by Pankaj Raghav's avatar Pankaj Raghav Committed by Christian Brauner
Browse files

fs/libfs: don't assume blocksize <= PAGE_SIZE in generic_check_addressable 

Since [1], it is possible for filesystems to have blocksize > PAGE_SIZE
of the system.

Remove the assumption and make the check generic for all blocksizes in
generic_check_addressable().

[1] https://lore.kernel.org/linux-xfs/20240822135018.1931258-1-kernel@pankajraghav.com/



Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarPankaj Raghav <p.raghav@samsung.com>
Link: https://lore.kernel.org/20250630104018.213985-1-p.raghav@samsung.com


Reviewed-by: default avatarZhang Yi <yi.zhang@huawei.com>
Reviewed-by: default avatarBaokun Li <libaokun1@huawei.com>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 77eb6443

fs/libfs.c

+7 −3
Original line number Diff line number Diff line
@@ -1584,13 +1584,17 @@ EXPORT_SYMBOL(generic_file_fsync); 
int generic_check_addressable(unsigned blocksize_bits, u64 num_blocks)

{

	u64 last_fs_block = num_blocks - 1;

	u64 last_fs_page =

		last_fs_block >> (PAGE_SHIFT - blocksize_bits);

	u64 last_fs_page, max_bytes;



	if (check_shl_overflow(num_blocks, blocksize_bits, &max_bytes))

		return -EFBIG;



	last_fs_page = (max_bytes >> PAGE_SHIFT) - 1;



	if (unlikely(num_blocks == 0))

		return 0;



	if ((blocksize_bits < 9) || (blocksize_bits > PAGE_SHIFT))

	if (blocksize_bits < 9)

		return -EINVAL;



	if ((last_fs_block > (sector_t)(~0ULL) >> (blocksize_bits - 9)) ||