From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann Droneaud Subject: [PATCH v1 1/2] IB/core: disallow registering 0-sized memory region Date: Mon, 13 Apr 2015 14:56:22 +0200 Message-ID: <0e246088b73c1eb19fb4cc20a1aefcb08919087d.1428929103.git.ydroneaud@opteya.com> References: Return-path: In-Reply-To: In-Reply-To: References: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Roland Dreier Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Shachar Raindel , Jack Morgenstein , Or Gerlitz , stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Yann Droneaud List-Id: linux-rdma@vger.kernel.org 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.ydroneaud-RlY5vtjFyJ3QT0dZR+AlfA@public.gmane.org Cc: Cc: Shachar Raindel Cc: Jack Morgenstein Cc: Or Gerlitz Signed-off-by: Yann Droneaud --- 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 majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html