OpenE2K/linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

tipc: check tsk->group in tipc_wait_for_cond()

Browse Source 
tipc_wait_for_cond() drops socket lock before going to sleep,
but tsk->group could be freed right after that release_sock().
So we have to re-check and reload tsk->group after it wakes up.

After this patch, tipc_wait_for_cond() returns -ERESTARTSYS when
tsk->group is NULL, instead of continuing with the assumption of
a non-NULL tsk->group.

(It looks like 'dsts' should be re-checked and reloaded too, but
it is a different bug.)

Similar for tipc_send_group_unicast() and tipc_send_group_anycast().

Reported-by: syzbot+10a9db47c3a0e13eb31c@syzkaller.appspotmail.com
Fixes: b7d4263551 ("tipc: introduce flow control for group broadcast messages")
Fixes: ee106d7f94 ("tipc: introduce group anycast messaging")
Fixes: 27bd9ec027 ("tipc: introduce group unicast messaging")
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Cong Wang 2018-12-11 21:43:51 -08:00 committed by David S. Miller
parent 65cab850f0
commit 143ece654f
1 changed files with 14 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
net/tipc/socket.c
View File

@ -880,7 +880,6 @@ static int tipc_send_group_unicast(struct socket *sock, struct msghdr *m,
DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
int blks = tsk_blocks(GROUP_H_SIZE + dlen);
struct tipc_sock *tsk = tipc_sk(sk);
struct tipc_group *grp = tsk->group;
struct net *net = sock_net(sk);
struct tipc_member *mb = NULL;
u32 node, port;
@ -894,7 +893,9 @@ static int tipc_send_group_unicast(struct socket *sock, struct msghdr *m,
/* Block or return if destination link or member is congested */
rc = tipc_wait_for_cond(sock, &timeout,
!tipc_dest_find(&tsk->cong_links, node, 0) &&
!tipc_group_cong(grp, node, port, blks, &mb));
tsk->group &&
!tipc_group_cong(tsk->group, node, port, blks,
&mb));
if (unlikely(rc))
return rc;
@ -924,7 +925,6 @@ static int tipc_send_group_anycast(struct socket *sock, struct msghdr *m,
struct tipc_sock *tsk = tipc_sk(sk);
struct list_head *cong_links = &tsk->cong_links;
int blks = tsk_blocks(GROUP_H_SIZE + dlen);
struct tipc_group *grp = tsk->group;
struct tipc_msg *hdr = &tsk->phdr;
struct tipc_member *first = NULL;
struct tipc_member *mbr = NULL;
@ -941,9 +941,10 @@ static int tipc_send_group_anycast(struct socket *sock, struct msghdr *m,
type = msg_nametype(hdr);
inst = dest->addr.name.name.instance;
scope = msg_lookup_scope(hdr);
exclude = tipc_group_exclude(grp);
while (++lookups < 4) {
exclude = tipc_group_exclude(tsk->group);
first = NULL;
/* Look for a non-congested destination member, if any */
@ -952,7 +953,8 @@ static int tipc_send_group_anycast(struct socket *sock, struct msghdr *m,
&dstcnt, exclude, false))
return -EHOSTUNREACH;
tipc_dest_pop(&dsts, &node, &port);
cong = tipc_group_cong(grp, node, port, blks, &mbr);
cong = tipc_group_cong(tsk->group, node, port, blks,
&mbr);
if (!cong)
break;
if (mbr == first)
@ -971,7 +973,8 @@ static int tipc_send_group_anycast(struct socket *sock, struct msghdr *m,
/* Block or return if destination link or member is congested */
rc = tipc_wait_for_cond(sock, &timeout,
!tipc_dest_find(cong_links, node, 0) &&
!tipc_group_cong(grp, node, port,
tsk->group &&
!tipc_group_cong(tsk->group, node, port,
blks, &mbr));
if (unlikely(rc))
return rc;
@ -1006,8 +1009,7 @@ static int tipc_send_group_bcast(struct socket *sock, struct msghdr *m,
struct sock *sk = sock->sk;
struct net *net = sock_net(sk);
struct tipc_sock *tsk = tipc_sk(sk);
struct tipc_group *grp = tsk->group;
struct tipc_nlist *dsts = tipc_group_dests(grp);
struct tipc_nlist *dsts = tipc_group_dests(tsk->group);
struct tipc_mc_method *method = &tsk->mc_method;
bool ack = method->mandatory && method->rcast;
int blks = tsk_blocks(MCAST_H_SIZE + dlen);
@ -1020,8 +1022,9 @@ static int tipc_send_group_bcast(struct socket *sock, struct msghdr *m,
return -EHOSTUNREACH;
/* Block or return if any destination link or member is congested */
rc = tipc_wait_for_cond(sock, &timeout, !tsk->cong_link_cnt &&
!tipc_group_bc_cong(grp, blks));
rc = tipc_wait_for_cond(sock, &timeout,
!tsk->cong_link_cnt && tsk->group &&
!tipc_group_bc_cong(tsk->group, blks));
if (unlikely(rc))
return rc;
@ -1036,7 +1039,7 @@ static int tipc_send_group_bcast(struct socket *sock, struct msghdr *m,
msg_set_hdr_sz(hdr, GROUP_H_SIZE);
msg_set_destport(hdr, 0);
msg_set_destnode(hdr, 0);
msg_set_grp_bc_seqno(hdr, tipc_group_bc_snd_nxt(grp));
msg_set_grp_bc_seqno(hdr, tipc_group_bc_snd_nxt(tsk->group));
/* Avoid getting stuck with repeated forced replicasts */
msg_set_grp_bc_ack_req(hdr, ack);