* [PATCH] erofs: fix order >= MAX_ORDER warning due to crafted nagative i_size
[not found] <000000000000ac8efa05e7feaa1f@google.com>
@ 2022-09-09 2:39 ` Gao Xiang
2022-09-19 1:37 ` Yue Hu
0 siblings, 1 reply; 2+ messages in thread
From: Gao Xiang @ 2022-09-09 2:39 UTC (permalink / raw)
To: linux-erofs; +Cc: Gao Xiang, syzbot+f966c13b1b4fc0403b19, syzkaller-bugs, LKML
As syzbot reported [1], the root cause is that i_size field is a
signed type, and negative i_size is also less than EROFS_BLKSIZ.
As a consequence, it's handled as fast symlink unexpectedly.
Let's fall back to the generic path to deal with such unusual i_size.
[1] https://lore.kernel.org/r/000000000000ac8efa05e7feaa1f@google.com
Reported-by: syzbot+f966c13b1b4fc0403b19@syzkaller.appspotmail.com
Fixes: 431339ba9042 ("staging: erofs: add inode operations")
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
fs/erofs/inode.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 95a403720e8c..16cf9a283557 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -214,7 +214,7 @@ static int erofs_fill_symlink(struct inode *inode, void *kaddr,
/* if it cannot be handled with fast symlink scheme */
if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
- inode->i_size >= EROFS_BLKSIZ) {
+ inode->i_size >= EROFS_BLKSIZ || inode->i_size < 0) {
inode->i_op = &erofs_symlink_iops;
return 0;
}
--
2.24.4
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH] erofs: fix order >= MAX_ORDER warning due to crafted nagative i_size
2022-09-09 2:39 ` [PATCH] erofs: fix order >= MAX_ORDER warning due to crafted nagative i_size Gao Xiang
@ 2022-09-19 1:37 ` Yue Hu
0 siblings, 0 replies; 2+ messages in thread
From: Yue Hu @ 2022-09-19 1:37 UTC (permalink / raw)
To: Gao Xiang; +Cc: syzkaller-bugs, syzbot+f966c13b1b4fc0403b19, linux-erofs, LKML
On Fri, 9 Sep 2022 10:39:48 +0800
Gao Xiang <hsiangkao@linux.alibaba.com> wrote:
> As syzbot reported [1], the root cause is that i_size field is a
> signed type, and negative i_size is also less than EROFS_BLKSIZ.
> As a consequence, it's handled as fast symlink unexpectedly.
>
> Let's fall back to the generic path to deal with such unusual i_size.
>
> [1] https://lore.kernel.org/r/000000000000ac8efa05e7feaa1f@google.com
> Reported-by: syzbot+f966c13b1b4fc0403b19@syzkaller.appspotmail.com
> Fixes: 431339ba9042 ("staging: erofs: add inode operations")
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
> ---
> fs/erofs/inode.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
> index 95a403720e8c..16cf9a283557 100644
> --- a/fs/erofs/inode.c
> +++ b/fs/erofs/inode.c
> @@ -214,7 +214,7 @@ static int erofs_fill_symlink(struct inode *inode, void *kaddr,
>
> /* if it cannot be handled with fast symlink scheme */
> if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
> - inode->i_size >= EROFS_BLKSIZ) {
> + inode->i_size >= EROFS_BLKSIZ || inode->i_size < 0) {
Reviewed-by: Yue Hu <huyue2@coolpad.com>
> inode->i_op = &erofs_symlink_iops;
> return 0;
> }
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2022-09-19 1:35 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
[not found] <000000000000ac8efa05e7feaa1f@google.com>
2022-09-09 2:39 ` [PATCH] erofs: fix order >= MAX_ORDER warning due to crafted nagative i_size Gao Xiang
2022-09-19 1:37 ` Yue Hu
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).