[PATCH for 4.9 29/59] IB/rxe: Add a runtime check in alloc_index()

From: Levin, Alexander (Sasha Levin)
Date: Thu Sep 14 2017 - 11:52:45 EST


From: Bart Van Assche <bart.vanassche@xxxxxxxxxxx>

[ Upstream commit 642c7cbcaf2ffc1e27f67eda3dc47347ac5aff37 ]

Since index values equal to or above 'range' can trigger memory
corruption, complain if index >= range.

Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxxxxxx>
Reviewed-by: Andrew Boyer <andrew.boyer@xxxxxxxx>
Cc: Moni Shoua <monis@xxxxxxxxxxxx>
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
drivers/infiniband/sw/rxe/rxe_pool.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c
index 6bac0717c540..ee26a1b1b4ed 100644
--- a/drivers/infiniband/sw/rxe/rxe_pool.c
+++ b/drivers/infiniband/sw/rxe/rxe_pool.c
@@ -274,6 +274,7 @@ static u32 alloc_index(struct rxe_pool *pool)
if (index >= range)
index = find_first_zero_bit(pool->table, range);

+ WARN_ON_ONCE(index >= range);
set_bit(index, pool->table);
pool->last = index;
return index + pool->min_index;
--
2.11.0