[RESEND PATCH] net: qrtr: fix another OOB Read in qrtr_endpoint_post

[RESEND PATCH] net: qrtr: fix another OOB Read in qrtr_endpoint_post

[Xiaolong Huang]

This check was incomplete, did not consider size is 0:

	if (len != ALIGN(size, 4) + hdrlen)
                    goto err;

if size from qrtr_hdr is 0, the result of ALIGN(size, 4)
will be 0, In case of len == hdrlen and size == 0
in header this check won't fail and

	if (cb->type == QRTR_TYPE_NEW_SERVER) {
                /* Remote node endpoint can bridge other distant nodes */
                const struct qrtr_ctrl_pkt *pkt = data + hdrlen;

                qrtr_node_assign(node, le32_to_cpu(pkt->server.node));
        }

will also read out of bound from data, which is hdrlen allocated block.

Fixes: 194ccc88297a ("net: qrtr: Support decoding incoming v2 packets")
Fixes: ad9d24c9429e ("net: qrtr: fix OOB Read in qrtr_endpoint_post")
Signed-off-by: Xiaolong Huang <butterflyhuangxx@gmail.com>

---

Reason for resend:
1. Modify the spelling error of signed-off-by email address.
2. Use real name.
---
 net/qrtr/qrtr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c
index 171b7f3be6ef..0c30908628ba 100644
--- a/net/qrtr/qrtr.c
+++ b/net/qrtr/qrtr.c
@@ -493,7 +493,7 @@ int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len)
 		goto err;
 	}
 
-	if (len != ALIGN(size, 4) + hdrlen)
+	if (!size || len != ALIGN(size, 4) + hdrlen)
 		goto err;
 
 	if (cb->dst_port != QRTR_PORT_CTRL && cb->type != QRTR_TYPE_DATA &&
-- 
2.25.1

Re: [RESEND PATCH] net: qrtr: fix another OOB Read in qrtr_endpoint_post

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net.git (refs/heads/master):

On Fri, 20 Aug 2021 03:50:34 +0800 you wrote:
> This check was incomplete, did not consider size is 0:
> 
> 	if (len != ALIGN(size, 4) + hdrlen)
>                     goto err;
> 
> if size from qrtr_hdr is 0, the result of ALIGN(size, 4)
> will be 0, In case of len == hdrlen and size == 0
> in header this check won't fail and
> 
> [...]

Here is the summary with links:
  - [RESEND] net: qrtr: fix another OOB Read in qrtr_endpoint_post
    https://git.kernel.org/netdev/net/c/7e78c597c3eb

You are awesome, thank you!
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