[PATCH 3.10 259/268] p9_client_readdir() fix

Willy Tarreau
2017-06-19T18:36:40Z

From: Al Viro <viro@zeniv.linux.org.uk>

commit 71d6ad08379304128e4bdfaf0b4185d54375423e upstream.

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

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
net/9p/client.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/net/9p/client.c b/net/9p/client.c
index 853d623..e191aab 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -2080,6 +2080,10 @@ 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);

--
2.8.0.rc2.1.gbe9624a