[PATCH] SUNRPC: Fix crasher in gss_unwrap_resp_integ()
From: Chuck Lever <chuck.lever@oracle.com>
Date: 2022-10-08 19:00:10
Subsystem:
kernel nfsd, sunrpc, and lockd servers, networking [general], nfs, sunrpc, and lockd clients, the rest · Maintainers:
Chuck Lever, Jeff Layton, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Trond Myklebust, Anna Schumaker, Linus Torvalds
If a zero length is passed to kmalloc() it returns 0x10, which is not a valid address. gss_unwrap_resp_integ() subsequently crashes when it attempts to dereference that pointer. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> --- net/sunrpc/auth_gss/auth_gss.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index a31a27816cc0..7bb247c51e2f 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c@@ -1989,7 +1989,7 @@ gss_unwrap_resp_integ(struct rpc_task *task, struct rpc_cred *cred, goto unwrap_failed; mic.len = len; mic.data = kmalloc(len, GFP_KERNEL); - if (!mic.data) + if (ZERO_OR_NULL_PTR(mic.data)) goto unwrap_failed; if (read_bytes_from_xdr_buf(rcv_buf, offset, mic.data, mic.len)) goto unwrap_failed;