linux/net/rds
Pavel Skripkin 49bfcbfd98 net: rds: fix memory leak in rds_recvmsg
Syzbot reported memory leak in rds. The problem
was in unputted refcount in case of error.

int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
		int msg_flags)
{
...

	if (!rds_next_incoming(rs, &inc)) {
		...
	}

After this "if" inc refcount incremented and

	if (rds_cmsg_recv(inc, msg, rs)) {
		ret = -EFAULT;
		goto out;
	}
...
out:
	return ret;
}

in case of rds_cmsg_recv() fail the refcount won't be
decremented. And it's easy to see from ftrace log, that
rds_inc_addref() don't have rds_inc_put() pair in
rds_recvmsg() after rds_cmsg_recv()

 1)               |  rds_recvmsg() {
 1)   3.721 us    |    rds_inc_addref();
 1)   3.853 us    |    rds_message_inc_copy_to_user();
 1) + 10.395 us   |    rds_cmsg_recv();
 1) + 34.260 us   |  }

Fixes: bdbe6fbc6a ("RDS: recv.c")
Reported-and-tested-by: syzbot+5134cdf021c4ed5aaa5f@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Reviewed-by: Håkon Bugge <haakon.bugge@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-08 16:32:17 -07:00
..
af_rds.c net: pass a sockptr_t into ->setsockopt 2020-07-24 15:41:54 -07:00
bind.c net/rds: Check laddr_check before calling it 2019-09-27 12:10:55 +02:00
cong.c net: rds: delete duplicated words 2020-09-18 14:12:43 -07:00
connection.c RDS tcp loopback connection can hang 2021-05-21 14:46:59 -07:00
ib_cm.c rds: ib: Remove two ib_modify_qp() calls 2021-04-12 19:51:48 -03:00
ib_frmr.c RDMA/rds: Remove FMR support for memory registration 2020-06-02 20:32:53 -03:00
ib_mr.h RDMA/rds: Remove FMR support for memory registration 2020-06-02 20:32:53 -03:00
ib_rdma.c RDMA/rds: Remove FMR support for memory registration 2020-06-02 20:32:53 -03:00
ib_recv.c rds: stop using dmapool 2020-11-17 15:22:06 -04:00
ib_ring.c
ib_send.c rds: Remove redundant assignment to nr_sig 2021-04-27 14:14:33 -07:00
ib_stats.c net/rds: Fix 'ib_evt_handler_call' element in 'rds_ib_stat_names' 2019-09-15 20:56:19 +02:00
ib_sysctl.c
ib.c rds: stop using dmapool 2020-11-17 15:22:06 -04:00
ib.h rds: stop using dmapool 2020-11-17 15:22:06 -04:00
info.c rds: fix crash in rds_info_getsockopt() 2020-05-20 14:08:06 -07:00
info.h
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
loop.c
loop.h
Makefile RDMA/rds: Remove FMR support for memory registration 2020-06-02 20:32:53 -03:00
message.c Revert "net/rds: Avoid potential use after free in rds_send_remove_from_sock" 2021-04-24 09:32:35 -07:00
page.c
rdma_transport.c rds: ib: Remove two ib_modify_qp() calls 2021-04-12 19:51:48 -03:00
rdma_transport.h net: rds: rdma_transport.h: delete duplicated word 2020-07-19 18:14:51 -07:00
rdma.c net/rds: restrict iovecs length for RDS_CMSG_RDMA_ARGS 2021-02-02 08:44:08 -08:00
rds_single_path.h
rds.h net: pass a sockptr_t into ->setsockopt 2020-07-24 15:41:54 -07:00
recv.c net: rds: fix memory leak in rds_recvmsg 2021-06-08 16:32:17 -07:00
send.c Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
stats.c rds: check for excessive looping in rds_send_xmit 2019-08-15 12:04:24 -07:00
sysctl.c
tcp_connect.c net: add sock_no_linger 2020-05-28 11:11:44 -07:00
tcp_listen.c RDS tcp loopback connection can hang 2021-05-21 14:46:59 -07:00
tcp_recv.c
tcp_send.c tcp: add tcp_sock_set_cork 2020-05-28 11:11:45 -07:00
tcp_stats.c
tcp.c RDS tcp loopback connection can hang 2021-05-21 14:46:59 -07:00
tcp.h RDS tcp loopback connection can hang 2021-05-21 14:46:59 -07:00
threads.c rds: make v3.1 as compat version 2019-02-04 14:59:11 -08:00
transport.c rds: transport module should be auto loaded when transport is set 2020-06-25 16:26:25 -07:00