From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 14 Apr 2017 21:22:18 +0000 (-0400)
Subject: p9_client_readdir() fix
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=71d6ad08379304128e4bdfaf0b4185d54375423e;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

p9_client_readdir() fix

Don't assume that server is sane and won't return more data than
asked for.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/net/9p/client.c b/net/9p/client.c
index 3ce672af1596..8e5c6a8d0a37 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -2101,6 +2101,10 @@ int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
 		trace_9p_protocol_dump(clnt, req->rc);
 		goto free_and_error;
 	}
+	if (rsize < count) {
+		pr_err("bogus RREADDIR count (%d > %d)\n", count, rsize);
+		count = rsize;
+	}
 
 	p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);