diff options
| author | Jon Maloy <jon.maloy@ericsson.com> | 2018-01-17 16:42:46 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-01-19 15:12:21 -0500 |
| commit | 60c2530696320ee6ffe4491c17079fa403790c98 (patch) | |
| tree | 619bdaecd86e48c1962a6866e40ada7e09c5addc /net/tipc/group.c | |
| parent | 30c3e9d470358a6741e00e1034a1ea85c6a516f0 (diff) | |
| download | linux-60c2530696320ee6ffe4491c17079fa403790c98.tar.bz2 | |
tipc: fix race between poll() and setsockopt()
Letting tipc_poll() dereference a socket's pointer to struct tipc_group
entails a race risk, as the group item may be deleted in a concurrent
tipc_sk_join() or tipc_sk_leave() thread.
We now move the 'open' flag in struct tipc_group to struct tipc_sock,
and let the former retain only a pointer to the moved field. This will
eliminate the race risk.
Reported-by: syzbot+799dafde0286795858ac@syzkaller.appspotmail.com
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/tipc/group.c')
| -rw-r--r-- | net/tipc/group.c | 19 |
1 files changed, 8 insertions, 11 deletions
diff --git a/net/tipc/group.c b/net/tipc/group.c index 497ee34bfab9..122162a31816 100644 --- a/net/tipc/group.c +++ b/net/tipc/group.c @@ -93,26 +93,21 @@ struct tipc_group { u16 max_active; u16 bc_snd_nxt; u16 bc_ackers; + bool *open; bool loopback; bool events; - bool open; }; static void tipc_group_proto_xmit(struct tipc_group *grp, struct tipc_member *m, int mtyp, struct sk_buff_head *xmitq); -bool tipc_group_is_open(struct tipc_group *grp) -{ - return grp->open; -} - static void tipc_group_open(struct tipc_member *m, bool *wakeup) { *wakeup = false; if (list_empty(&m->small_win)) return; list_del_init(&m->small_win); - m->group->open = true; + *m->group->open = true; *wakeup = true; } @@ -170,7 +165,8 @@ int tipc_group_size(struct tipc_group *grp) } struct tipc_group *tipc_group_create(struct net *net, u32 portid, - struct tipc_group_req *mreq) + struct tipc_group_req *mreq, + bool *group_is_open) { u32 filter = TIPC_SUB_PORTS | TIPC_SUB_NO_STATUS; bool global = mreq->scope != TIPC_NODE_SCOPE; @@ -192,6 +188,7 @@ struct tipc_group *tipc_group_create(struct net *net, u32 portid, grp->scope = mreq->scope; grp->loopback = mreq->flags & TIPC_GROUP_LOOPBACK; grp->events = mreq->flags & TIPC_GROUP_MEMBER_EVTS; + grp->open = group_is_open; filter |= global ? TIPC_SUB_CLUSTER_SCOPE : TIPC_SUB_NODE_SCOPE; if (tipc_topsrv_kern_subscr(net, portid, type, 0, ~0, filter, &grp->subid)) @@ -430,7 +427,7 @@ bool tipc_group_cong(struct tipc_group *grp, u32 dnode, u32 dport, if (m->window >= len) return false; - grp->open = false; + *grp->open = false; /* If not fully advertised, do it now to prevent mutual blocking */ adv = m->advertised; @@ -453,7 +450,7 @@ bool tipc_group_bc_cong(struct tipc_group *grp, int len) /* If prev bcast was replicast, reject until all receivers have acked */ if (grp->bc_ackers) { - grp->open = false; + *grp->open = false; return true; } if (list_empty(&grp->small_win)) @@ -800,7 +797,7 @@ void tipc_group_proto_rcv(struct tipc_group *grp, bool *usr_wakeup, if (--grp->bc_ackers) return; list_del_init(&m->small_win); - m->group->open = true; + *m->group->open = true; *usr_wakeup = true; tipc_group_update_member(m, 0); return; |