4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mohamed Ghannam <simo.ghannam@xxxxxxxxx>
[ Upstream commit c095508770aebf1b9218e77026e48345d719b17c ]
When args->nr_local is 0, nr_pages gets also 0 due some size
calculation via rds_rm_size(), which is later used to allocate
pages for DMA, this bug produces a heap Out-Of-Bound write access
to a specific memory region.
Signed-off-by: Mohamed Ghannam <simo.ghannam@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/rds/rdma.c | 3 +++
1 file changed, 3 insertions(+)
--- a/net/rds/rdma.c
+++ b/net/rds/rdma.c
@@ -517,6 +517,9 @@ int rds_rdma_extra_size(struct rds_rdma_
local_vec = (struct rds_iovec __user *)(unsigned long) args->local_vec_addr;
+ if (args->nr_local == 0)
+ return -EINVAL;
+
/* figure out the number of pages in the vector */
for (i = 0; i < args->nr_local; i++) {
if (copy_from_user(&vec, &local_vec[i],