From: Peilin Ye yepeilin.cs@gmail.com
[ Upstream commit bb3a420d47ab00d7e1e5083286cab15235a96680 ]
tipc_group_add_to_tree() returns silently if `key` matches `nkey` of an existing node, causing tipc_group_create_member() to leak memory. Let tipc_group_add_to_tree() return an error in such a case, so that tipc_group_create_member() can handle it properly.
Fixes: 75da2163dbb6 ("tipc: introduce communication groups") Reported-and-tested-by: syzbot+f95d90c454864b3b5bc9@syzkaller.appspotmail.com Cc: Hillf Danton hdanton@sina.com Link: https://syzkaller.appspot.com/bug?id=048390604fe1b60df34150265479202f10e13af... Signed-off-by: Peilin Ye yepeilin.cs@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/tipc/group.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)
--- a/net/tipc/group.c +++ b/net/tipc/group.c @@ -273,8 +273,8 @@ static struct tipc_member *tipc_group_fi return NULL; }
-static void tipc_group_add_to_tree(struct tipc_group *grp, - struct tipc_member *m) +static int tipc_group_add_to_tree(struct tipc_group *grp, + struct tipc_member *m) { u64 nkey, key = (u64)m->node << 32 | m->port; struct rb_node **n, *parent = NULL; @@ -291,10 +291,11 @@ static void tipc_group_add_to_tree(struc else if (key > nkey) n = &(*n)->rb_right; else - return; + return -EEXIST; } rb_link_node(&m->tree_node, parent, n); rb_insert_color(&m->tree_node, &grp->members); + return 0; }
static struct tipc_member *tipc_group_create_member(struct tipc_group *grp, @@ -302,6 +303,7 @@ static struct tipc_member *tipc_group_cr u32 instance, int state) { struct tipc_member *m; + int ret;
m = kzalloc(sizeof(*m), GFP_ATOMIC); if (!m) @@ -314,8 +316,12 @@ static struct tipc_member *tipc_group_cr m->port = port; m->instance = instance; m->bc_acked = grp->bc_snd_nxt - 1; + ret = tipc_group_add_to_tree(grp, m); + if (ret < 0) { + kfree(m); + return NULL; + } grp->member_cnt++; - tipc_group_add_to_tree(grp, m); tipc_nlist_add(&grp->dests, m->node); m->state = state; return m;