diff options
| author | Eric Dumazet <edumazet@google.com> | 2024-11-21 20:41:05 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-11-25 01:43:13 +0100 |
| commit | 9b234a97b10cf1385d451a3824539b774abbcdaf (patch) | |
| tree | b3618ef26bdc7667ab57b5b8d3dce59ecbd0cea2 /net | |
| parent | selftests: fix nested double quotes in f-string (diff) | |
| download | linux-9b234a97b10cf1385d451a3824539b774abbcdaf.tar.xz linux-9b234a97b10cf1385d451a3824539b774abbcdaf.zip | |
rtnetlink: fix rtnl_dump_ifinfo() error path
syzbot found that rtnl_dump_ifinfo() could return with a lock held [1]
Move code around so that rtnl_link_ops_put() and put_net()
can be called at the end of this function.
[1]
WARNING: lock held when returning to user space!
6.12.0-rc7-syzkaller-01681-g38f83a57aa8e #0 Not tainted
syz-executor399/5841 is leaving the kernel with locks still held!
1 lock held by syz-executor399/5841:
#0: ffffffff8f46c2a0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8f46c2a0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8f46c2a0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:555
Fixes: 43c7ce69d28e ("rtnetlink: Protect struct rtnl_link_ops with SRCU.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20241121194105.3632507-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/rtnetlink.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index dd142f444659..58df76fe408a 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2442,7 +2442,9 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) tgt_net = rtnl_get_net_ns_capable(skb->sk, netnsid); if (IS_ERR(tgt_net)) { NL_SET_ERR_MSG(extack, "Invalid target network namespace id"); - return PTR_ERR(tgt_net); + err = PTR_ERR(tgt_net); + netnsid = -1; + goto out; } break; case IFLA_EXT_MASK: @@ -2457,7 +2459,8 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) default: if (cb->strict_check) { NL_SET_ERR_MSG(extack, "Unsupported attribute in link dump request"); - return -EINVAL; + err = -EINVAL; + goto out; } } } @@ -2479,11 +2482,14 @@ walk_entries: break; } - if (kind_ops) - rtnl_link_ops_put(kind_ops, ops_srcu_index); cb->seq = tgt_net->dev_base_seq; nl_dump_check_consistent(cb, nlmsg_hdr(skb)); + +out: + + if (kind_ops) + rtnl_link_ops_put(kind_ops, ops_srcu_index); if (netnsid >= 0) put_net(tgt_net); |