On 09/12/2020 12:48, 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.
buf_cmd should be a ssp_tmf_iu struct through the analysis of
hmmm... but you change the !tmf path.
the command below:
buf_cmd = hisi_sas_cmd_hdr_addr_mem(slot) +
sizeof(struct ssp_frame_hdr);
Then buf_cmd + 12 should point to tag, so the length parameter
of memcpy() should not exceed sizeof(__be16)+sizeof(u8)*14):
struct ssp_tmf_iu {
u8 lun[8];
u16 _r_a;
u8 tmf;
u8 _r_b;
__be16 tag;
u8 _r_c[14];
} __attribute__ ((packed));
Signed-off-by: Zhang Xiaohui <ruc_zhangxiaohui@xxxxxxx>
---
drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 4 +++-
1 file changed, 3 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..d02831c17 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -1267,7 +1267,9 @@ 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,
+ sizeof(__be16) + sizeof(u8) * 14));
Again, this is not the right thing to do, and I don't think that this
code needs fixing at all.
There should be a contract already that the driver is not sent cdb len >
16, and this is sizeof(ssp_command_iu.cdb).
And, if we were sent too much data, then we would/should error.
Thanks,
John
