[PATCH] drivers/infiniband: copy userspace arrays safely

From: Philipp Stanner
Date: Thu Nov 02 2023 - 15:14:19 EST


Currently, memdup_user() is utilized at two positions to copy userspace
arrays. This is done without overflow checks.

Use the new wrapper memdup_array_user() to copy the arrays more safely.

Suggested-by: Dave Airlie <airlied@xxxxxxxxxx>
Signed-off-by: Philipp Stanner <pstanner@xxxxxxxxxx>
---
drivers/infiniband/hw/hfi1/user_exp_rcv.c | 4 ++--
drivers/infiniband/hw/hfi1/user_sdma.c | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/infiniband/hw/hfi1/user_exp_rcv.c b/drivers/infiniband/hw/hfi1/user_exp_rcv.c
index 96058baf36ed..53a623892d9d 100644
--- a/drivers/infiniband/hw/hfi1/user_exp_rcv.c
+++ b/drivers/infiniband/hw/hfi1/user_exp_rcv.c
@@ -491,8 +491,8 @@ int hfi1_user_exp_rcv_clear(struct hfi1_filedata *fd,
if (unlikely(tinfo->tidcnt > fd->tid_used))
return -EINVAL;

- tidinfo = memdup_user(u64_to_user_ptr(tinfo->tidlist),
- sizeof(tidinfo[0]) * tinfo->tidcnt);
+ tidinfo = memdup_array_user(u64_to_user_ptr(tinfo->tidlist),
+ tinfo->tidcnt, sizeof(tidinfo[0]));
if (IS_ERR(tidinfo))
return PTR_ERR(tidinfo);

diff --git a/drivers/infiniband/hw/hfi1/user_sdma.c b/drivers/infiniband/hw/hfi1/user_sdma.c
index 29ae7beb9b03..f7fa8e699a78 100644
--- a/drivers/infiniband/hw/hfi1/user_sdma.c
+++ b/drivers/infiniband/hw/hfi1/user_sdma.c
@@ -494,8 +494,8 @@ int hfi1_user_sdma_process_request(struct hfi1_filedata *fd,
* equal to the pkt count. However, there is no way to
* tell at this point.
*/
- tmp = memdup_user(iovec[idx].iov_base,
- ntids * sizeof(*req->tids));
+ tmp = memdup_array_user(iovec[idx].iov_base,
+ ntids, sizeof(*req->tids));
if (IS_ERR(tmp)) {
ret = PTR_ERR(tmp);
SDMA_DBG(req, "Failed to copy %d TIDs (%d)",
--
2.41.0