If ib_umem_get() is called with a size equal to 0 and an
non-page aligned address, one page will be pinned and a
0-sized umem will be returned to the caller.

This should not be allowed: it's not expected for a memory
region to have a size equal to 0.

This patch adds a check to explicitly refuse to register
a 0-sized region.

Link: http://mid.gmane.org/cover.1428929103.git.ydrone...@opteya.com
Cc: <sta...@vger.kernel.org>
Cc: Shachar Raindel <rain...@mellanox.com>
Cc: Jack Morgenstein <ja...@mellanox.com>
Cc: Or Gerlitz <ogerl...@mellanox.com>
Signed-off-by: Yann Droneaud <ydrone...@opteya.com>
---
 drivers/infiniband/core/umem.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c
index 8c014b5dab4c..9ac4068d2088 100644
--- a/drivers/infiniband/core/umem.c
+++ b/drivers/infiniband/core/umem.c
@@ -99,6 +99,9 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, 
unsigned long addr,
        if (dmasync)
                dma_set_attr(DMA_ATTR_WRITE_BARRIER, &attrs);
 
+       if (!size)
+               return ERR_PTR(-EINVAL);
+
        /*
         * If the combination of the addr and size requested for this memory
         * region causes an integer overflow, return error.
-- 
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to