RDS: Heap OOB write in rds_message_alloc_sgs()

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@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Mohamed Ghannam 2018-01-02 19:44:34 +00:00 committed by David S. Miller
parent c0bace7984
commit c095508770
1 changed files with 3 additions and 0 deletions

View File

@ -525,6 +525,9 @@ int rds_rdma_extra_size(struct rds_rdma_args *args)
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],