From 8e2ef6abd4653b1cfeefe262017ecdd5eaf40fef Mon Sep 17 00:00:00 2001 From: Mao Wenan Date: Thu, 12 Sep 2019 12:02:17 +0800 Subject: sctp: change return type of sctp_get_port_local Currently sctp_get_port_local() returns a long which is either 0,1 or a pointer casted to long. It's neither of the callers use the return value since commit 62208f12451f ("net: sctp: simplify sctp_get_port"). Now two callers are sctp_get_port and sctp_do_bind, they actually assumend a casted to an int was the same as a pointer casted to a long, and they don't save the return value just check whether it is zero or non-zero, so it would better change return type from long to int for sctp_get_port_local. Signed-off-by: Mao Wenan Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- net/sctp/socket.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index ad8751891b00..1e26606683a8 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -309,7 +309,7 @@ static int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len) return retval; } -static long sctp_get_port_local(struct sock *, union sctp_addr *); +static int sctp_get_port_local(struct sock *, union sctp_addr *); /* Verify this is a valid sockaddr. */ static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt, @@ -7999,7 +7999,7 @@ static void sctp_unhash(struct sock *sk) static struct sctp_bind_bucket *sctp_bucket_create( struct sctp_bind_hashbucket *head, struct net *, unsigned short snum); -static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr) +static int sctp_get_port_local(struct sock *sk, union sctp_addr *addr) { struct sctp_sock *sp = sctp_sk(sk); bool reuse = (sk->sk_reuse || sp->reuse); @@ -8109,7 +8109,7 @@ pp_found: if (sctp_bind_addr_conflict(&ep2->base.bind_addr, addr, sp2, sp)) { - ret = (long)sk2; + ret = 1; goto fail_unlock; } } @@ -8181,7 +8181,7 @@ static int sctp_get_port(struct sock *sk, unsigned short snum) addr.v4.sin_port = htons(snum); /* Note: sk->sk_num gets filled in if ephemeral port request. */ - return !!sctp_get_port_local(sk, &addr); + return sctp_get_port_local(sk, &addr); } /* -- cgit From e0e4b8de10ad3affe83cc91a1cf6d1e48cca333e Mon Sep 17 00:00:00 2001 From: Mao Wenan Date: Thu, 12 Sep 2019 12:02:18 +0800 Subject: sctp: remove redundant assignment when call sctp_get_port_local There are more parentheses in if clause when call sctp_get_port_local in sctp_do_bind, and redundant assignment to 'ret'. This patch is to do cleanup. Signed-off-by: Mao Wenan Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- net/sctp/socket.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 1e26606683a8..5fe26ca6edbd 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -399,9 +399,8 @@ static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len) * detection. */ addr->v4.sin_port = htons(snum); - if ((ret = sctp_get_port_local(sk, addr))) { + if (sctp_get_port_local(sk, addr)) return -EADDRINUSE; - } /* Refresh ephemeral port. */ if (!bp->port) -- cgit From 29b99f54a8e63f871cf4060406d09fd8b0d744d8 Mon Sep 17 00:00:00 2001 From: Mao Wenan Date: Thu, 12 Sep 2019 12:02:19 +0800 Subject: sctp: destroy bucket if failed to bind addr There is one memory leak bug report: BUG: memory leak unreferenced object 0xffff8881dc4c5ec0 (size 40): comm "syz-executor.0", pid 5673, jiffies 4298198457 (age 27.578s) hex dump (first 32 bytes): 02 00 00 00 81 88 ff ff 00 00 00 00 00 00 00 00 ................ f8 63 3d c1 81 88 ff ff 00 00 00 00 00 00 00 00 .c=............. backtrace: [<0000000072006339>] sctp_get_port_local+0x2a1/0xa00 [sctp] [<00000000c7b379ec>] sctp_do_bind+0x176/0x2c0 [sctp] [<000000005be274a2>] sctp_bind+0x5a/0x80 [sctp] [<00000000b66b4044>] inet6_bind+0x59/0xd0 [ipv6] [<00000000c68c7f42>] __sys_bind+0x120/0x1f0 net/socket.c:1647 [<000000004513635b>] __do_sys_bind net/socket.c:1658 [inline] [<000000004513635b>] __se_sys_bind net/socket.c:1656 [inline] [<000000004513635b>] __x64_sys_bind+0x3e/0x50 net/socket.c:1656 [<0000000061f2501e>] do_syscall_64+0x72/0x2e0 arch/x86/entry/common.c:296 [<0000000003d1e05e>] entry_SYSCALL_64_after_hwframe+0x49/0xbe This is because in sctp_do_bind, if sctp_get_port_local is to create hash bucket successfully, and sctp_add_bind_addr failed to bind address, e.g return -ENOMEM, so memory leak found, it needs to destroy allocated bucket. Reported-by: Hulk Robot Signed-off-by: Mao Wenan Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- net/sctp/socket.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 5fe26ca6edbd..b083d4e66230 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -412,11 +412,13 @@ static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len) ret = sctp_add_bind_addr(bp, addr, af->sockaddr_len, SCTP_ADDR_SRC, GFP_ATOMIC); - /* Copy back into socket for getsockname() use. */ - if (!ret) { - inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num); - sp->pf->to_sk_saddr(addr, sk); + if (ret) { + sctp_put_port(sk); + return ret; } + /* Copy back into socket for getsockname() use. */ + inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num); + sp->pf->to_sk_saddr(addr, sk); return ret; } -- cgit