From e7942b9f2586fb15e1b898acc7c198ffd60aee4e Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 23 Apr 2009 19:32:48 -0400 Subject: SUNRPC: Switch one_sock_name() to use snprintf() Use snprintf() in one_sock_name() to prevent overflowing the output buffer. If the name doesn't fit in the buffer, the buffer is filled in with an empty string, and -ENAMETOOLONG is returned. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- net/sunrpc/svcsock.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) (limited to 'net/sunrpc') diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 032b52ea9541..61d4a3281f94 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -240,22 +240,27 @@ out: /* * Report socket names for nfsdfs */ -static int one_sock_name(char *buf, struct svc_sock *svsk) +static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining) { int len; switch(svsk->sk_sk->sk_family) { - case AF_INET: - len = sprintf(buf, "ipv4 %s %pI4 %d\n", + case PF_INET: + len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n", svsk->sk_sk->sk_protocol == IPPROTO_UDP ? "udp" : "tcp", &inet_sk(svsk->sk_sk)->rcv_saddr, inet_sk(svsk->sk_sk)->num); break; default: - len = sprintf(buf, "*unknown-%d*\n", + len = snprintf(buf, remaining, "*unknown-%d*\n", svsk->sk_sk->sk_family); } + + if (len >= remaining) { + *buf = '\0'; + return -ENAMETOOLONG; + } return len; } @@ -282,15 +287,21 @@ int svc_sock_names(struct svc_serv *serv, char *buf, const size_t buflen, if (!serv) return 0; + spin_lock_bh(&serv->sv_lock); list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list) { - int onelen = one_sock_name(buf+len, svsk); - if (toclose && strcmp(toclose, buf+len) == 0) + int onelen = svc_one_sock_name(svsk, buf + len, buflen - len); + if (onelen < 0) { + len = onelen; + break; + } + if (toclose && strcmp(toclose, buf + len) == 0) closesk = svsk; else len += onelen; } spin_unlock_bh(&serv->sv_lock); + if (closesk) /* Should unregister with portmap, but you cannot * unregister just one protocol... @@ -1195,7 +1206,7 @@ int svc_addsock(struct svc_serv *serv, const int fd, char *name_return, sockfd_put(so); return err; } - return one_sock_name(name_return, svsk); + return svc_one_sock_name(svsk, name_return, len); } EXPORT_SYMBOL_GPL(svc_addsock); -- cgit v1.2.3-59-g8ed1b