On 2/6/2023 10:07 AM, Zhong Jinghua wrote: > In loop_set_status_from_info(), lo->lo_offset and lo->lo_sizelimit should > be checked before reassignment, because if an overflow error occurs, the > original correct value will be changed to the wrong value, and it will not > be changed back. > > Modifying to the wrong value logic is always not quiet right, we hope to > optimize this. > > Signed-off-by: Zhong Jinghua <zhongjinghua@xxxxxxxxxx> LGTM > --- > v1->v2: Modify note: overflowing -> overflow > drivers/block/loop.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/block/loop.c b/drivers/block/loop.c > index 1518a6423279..1b35cbd029c7 100644 > --- a/drivers/block/loop.c > +++ b/drivers/block/loop.c > @@ -977,13 +977,13 @@ loop_set_status_from_info(struct loop_device *lo, > return -EINVAL; > } > > + /* Avoid assigning overflow values */ > + if (info->lo_offset > LLONG_MAX || info->lo_sizelimit > LLONG_MAX) > + return -EOVERFLOW; > + > lo->lo_offset = info->lo_offset; > lo->lo_sizelimit = info->lo_sizelimit; > > - /* loff_t vars have been assigned __u64 */ > - if (lo->lo_offset < 0 || lo->lo_sizelimit < 0) > - return -EOVERFLOW; > - > memcpy(lo->lo_file_name, info->lo_file_name, LO_NAME_SIZE); > lo->lo_file_name[LO_NAME_SIZE-1] = 0; > lo->lo_flags = info->lo_flags;
