Re: [PATCH] fsck.f2fs: check nid range before use to avoid segmentation fault

[Sheng Yong]

On 2017/12/15 14:26, Yunlong Song wrote:
> Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
> ---
>   fsck/fsck.c | 11 ++++++++++-
>   1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/fsck/fsck.c b/fsck/fsck.c
> index 11b8b0b..2212aa3 100644
> --- a/fsck/fsck.c
> +++ b/fsck/fsck.c
> @@ -14,6 +14,15 @@
>   char *tree_mark;
>   uint32_t tree_mark_size = 256;
>   
> +static inline int check_nid_range(struct f2fs_sb_info *sbi, nid_t nid)
> +{
> +    if (nid < F2FS_ROOT_INO(sbi))
> +        return -EINVAL;
> +    if (nid >= NM_I(sbi)->max_nid)
> +        return -EINVAL;
> +    return 0;
> +}
> +
Hi Yunlong,
I think you could use IS_VALID_NID() instead of check_nid_range. Maybe we could
add the check 'if (nid < F2FS_ROOT_INO(sbi))' to IS_VALID_NID().

thanks,
Sheng
>   int f2fs_set_main_bitmap(struct f2fs_sb_info *sbi, u32 blk, int type)
>   {
>   	struct f2fs_fsck *fsck = F2FS_FSCK(sbi);
> @@ -740,7 +749,7 @@ void fsck_chk_inode_blk(struct f2fs_sb_info *sbi, u32 nid,
>   	for (idx = 0; idx < 5; idx++) {
>   		u32 nid = le32_to_cpu(node_blk->i.i_nid[idx]);
>   
> -		if (nid != 0) {
> +		if (nid != 0 && !check_nid_range(sbi, nid)) {
>   			struct node_info ni;
>   
>   			get_node_info(sbi, nid, &ni);