On 08/12/2020 16:40, Xiaohui Zhang wrote:
From: Zhang Xiaohui <ruc_zhangxiaohui@xxxxxxx>
prep_ssp_v3_hw() calls memcpy() without checking the
destination size may trigger a buffer overflower, which a
local user could use to cause denial of service or the
execution of arbitrary code.
Fix it by putting the length check before calling memcpy().
Signed-off-by: Zhang Xiaohui <ruc_zhangxiaohui@xxxxxxx>
---
drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
index 7133ca859..2664c36d3 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -1267,7 +1267,8 @@ static void prep_ssp_v3_hw(struct hisi_hba *hisi_hba,
memcpy(buf_cmd, &task->ssp_task.LUN, 8);
if (!tmf) {
buf_cmd[9] = ssp_task->task_attr | (ssp_task->task_prio << 3);
- memcpy(buf_cmd + 12, scsi_cmnd->cmnd, scsi_cmnd->cmd_len);
+ memcpy(buf_cmd + 12, scsi_cmnd->cmnd,
+ min_t(unsigned short, scsi_cmnd->cmd_len, strlen(buf_cmd)-12));
buf_cmd is not a NULL-terminated string, it's actually a pointer to a
structure.
And you can see that we set buf_cmd[9] previously (which could set as
0), so how can you possibly rely on a strlen(buf_cmd) - 12 being sane?
Thanks,
john
} else {
buf_cmd[10] = tmf->tmf;
switch (tmf->tmf) {
