diff options
| author | Zhong Jinghua <zhongjinghua@huawei.com> | 2023-02-21 17:50:27 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2023-02-22 20:43:09 -0700 |
| commit | 9f6ad5d533d1c71e51bdd06a5712c4fbc8768dfa (patch) | |
| tree | 279a5d36c086e0096896304e9086546305181654 /drivers/block/loop.c | |
| parent | 9c7c4bc986932218fd0df9d2a100509772028fb1 (diff) | |
| download | linux-9f6ad5d533d1c71e51bdd06a5712c4fbc8768dfa.tar.gz | |
loop: loop_set_status_from_info() check before assignment
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.
More, the original patch did not solve the problem, the value was set and
ioctl returned an error, but the subsequent io used the value in the loop
driver, which still caused an alarm:
loop_handle_cmd
do_req_filebacked
loff_t pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
lo_rw_aio
cmd->iocb.ki_pos = pos
Fixes: c490a0b5a4f3 ("loop: Check for overflow while configuring loop")
Signed-off-by: Zhong Jinghua <zhongjinghua@huawei.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20230221095027.3656193-1-zhongjinghua@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block/loop.c')
| -rw-r--r-- | drivers/block/loop.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 5f04235e4ff75f..839373451c2b7d 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; |