From: Reuben Hawkins reubenhwk@gmail.com

stable inclusion from stable-4.19.299 commit 70409dcd485a244b9f508aa6cdb21ac899a85dc1 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8L190 CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

------------------------------------------- [ Upstream commit 7116c0af4b8414b2f19fdb366eea213cbd9d91c2 ]

Readahead was factored to call generic_fadvise. That refactor added an S_ISREG restriction which broke readahead on block devices.

In addition to S_ISREG, this change checks S_ISBLK to fix block device readahead. There is no change in behavior with any file type besides block devices in this change.

Fixes: 3d8f7615319b ("vfs: implement readahead(2) using POSIX_FADV_WILLNEED") Signed-off-by: Reuben Hawkins reubenhwk@gmail.com Link: https://lore.kernel.org/r/20231003015704.2415-1-reubenhwk@gmail.com Reviewed-by: Amir Goldstein amir73il@gmail.com Signed-off-by: Christian Brauner brauner@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Jinjiang Tu tujinjiang@huawei.com --- mm/readahead.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/readahead.c b/mm/readahead.c index 7a21199c6227..7d78f86fcf6f 100644 --- a/mm/readahead.c +++ b/mm/readahead.c @@ -659,7 +659,8 @@ ssize_t ksys_readahead(int fd, loff_t offset, size_t count) */ ret = -EINVAL; if (!f.file->f_mapping || !f.file->f_mapping->a_ops || - !S_ISREG(file_inode(f.file)->i_mode)) + (!S_ISREG(file_inode(f.file)->i_mode) && + !S_ISBLK(file_inode(f.file)->i_mode))) goto out;

ret = vfs_fadvise(f.file, offset, count, POSIX_FADV_WILLNEED);