| Message ID | 20221104103216.2576427-1-glider@google.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | c23fb2c82267638f9d206cb96bb93e1f93ad7828 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | ipv6: addrlabel: fix infoleak when sending struct ifaddrlblmsg to network | expand |
> > This patch ensures that the reserved field is always initialized. > > Reported-by: syzbot+3553517af6020c4f2813f1003fe76ef3cbffe98d@syzkaller.appspotmail.com My bad, should be: Reported-by: syzbot+fa5414772d5c445dac3c@syzkaller.appspotmail.com
>> >> This patch ensures that the reserved field is always initialized. >> >> Reported-by: syzbot+3553517af6020c4f2813f1003fe76ef3cbffe98d@syzkaller.appspotmail.com > > My bad, should be: > Reported-by: syzbot+fa5414772d5c445dac3c@syzkaller.appspotmail.com I see the command but can't find the corresponding bug. The email is sent to syzbot+HASH@syzkaller.appspotmail.com address but the HASH does not correspond to any known bug. Please double check the address.
On 11/4/22 4:32 AM, Alexander Potapenko wrote: > When copying a `struct ifaddrlblmsg` to the network, __ifal_reserved > remained uninitialized, resulting in a 1-byte infoleak: > > BUG: KMSAN: kernel-network-infoleak in __netdev_start_xmit ./include/linux/netdevice.h:4841 > __netdev_start_xmit ./include/linux/netdevice.h:4841 > netdev_start_xmit ./include/linux/netdevice.h:4857 > xmit_one net/core/dev.c:3590 > dev_hard_start_xmit+0x1dc/0x800 net/core/dev.c:3606 > __dev_queue_xmit+0x17e8/0x4350 net/core/dev.c:4256 > dev_queue_xmit ./include/linux/netdevice.h:3009 > __netlink_deliver_tap_skb net/netlink/af_netlink.c:307 > __netlink_deliver_tap+0x728/0xad0 net/netlink/af_netlink.c:325 > netlink_deliver_tap net/netlink/af_netlink.c:338 > __netlink_sendskb net/netlink/af_netlink.c:1263 > netlink_sendskb+0x1d9/0x200 net/netlink/af_netlink.c:1272 > netlink_unicast+0x56d/0xf50 net/netlink/af_netlink.c:1360 > nlmsg_unicast ./include/net/netlink.h:1061 > rtnl_unicast+0x5a/0x80 net/core/rtnetlink.c:758 > ip6addrlbl_get+0xfad/0x10f0 net/ipv6/addrlabel.c:628 > rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 > ... > Uninit was created at: > slab_post_alloc_hook+0x118/0xb00 mm/slab.h:742 > slab_alloc_node mm/slub.c:3398 > __kmem_cache_alloc_node+0x4f2/0x930 mm/slub.c:3437 > __do_kmalloc_node mm/slab_common.c:954 > __kmalloc_node_track_caller+0x117/0x3d0 mm/slab_common.c:975 > kmalloc_reserve net/core/skbuff.c:437 > __alloc_skb+0x27a/0xab0 net/core/skbuff.c:509 > alloc_skb ./include/linux/skbuff.h:1267 > nlmsg_new ./include/net/netlink.h:964 > ip6addrlbl_get+0x490/0x10f0 net/ipv6/addrlabel.c:608 > rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 > netlink_rcv_skb+0x299/0x550 net/netlink/af_netlink.c:2540 > rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:6109 > netlink_unicast_kernel net/netlink/af_netlink.c:1319 > netlink_unicast+0x9ab/0xf50 net/netlink/af_netlink.c:1345 > netlink_sendmsg+0xebc/0x10f0 net/netlink/af_netlink.c:1921 > ... > > This patch ensures that the reserved field is always initialized. > > Reported-by: syzbot+3553517af6020c4f2813f1003fe76ef3cbffe98d@syzkaller.appspotmail.com > Fixes: 2a8cc6c89039 ("[IPV6] ADDRCONF: Support RFC3484 configurable address selection policy table.") > Signed-off-by: Alexander Potapenko <glider@google.com> > --- > net/ipv6/addrlabel.c | 1 + > 1 file changed, 1 insertion(+) > Reviewed-by: David Ahern <dsahern@kernel.org>
> On 11/4/22 4:32 AM, Alexander Potapenko wrote: >> When copying a `struct ifaddrlblmsg` to the network, __ifal_reserved >> remained uninitialized, resulting in a 1-byte infoleak: >> >> BUG: KMSAN: kernel-network-infoleak in __netdev_start_xmit ./include/linux/netdevice.h:4841 >> __netdev_start_xmit ./include/linux/netdevice.h:4841 >> netdev_start_xmit ./include/linux/netdevice.h:4857 >> xmit_one net/core/dev.c:3590 >> dev_hard_start_xmit+0x1dc/0x800 net/core/dev.c:3606 >> __dev_queue_xmit+0x17e8/0x4350 net/core/dev.c:4256 >> dev_queue_xmit ./include/linux/netdevice.h:3009 >> __netlink_deliver_tap_skb net/netlink/af_netlink.c:307 >> __netlink_deliver_tap+0x728/0xad0 net/netlink/af_netlink.c:325 >> netlink_deliver_tap net/netlink/af_netlink.c:338 >> __netlink_sendskb net/netlink/af_netlink.c:1263 >> netlink_sendskb+0x1d9/0x200 net/netlink/af_netlink.c:1272 >> netlink_unicast+0x56d/0xf50 net/netlink/af_netlink.c:1360 >> nlmsg_unicast ./include/net/netlink.h:1061 >> rtnl_unicast+0x5a/0x80 net/core/rtnetlink.c:758 >> ip6addrlbl_get+0xfad/0x10f0 net/ipv6/addrlabel.c:628 >> rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 >> ... >> Uninit was created at: >> slab_post_alloc_hook+0x118/0xb00 mm/slab.h:742 >> slab_alloc_node mm/slub.c:3398 >> __kmem_cache_alloc_node+0x4f2/0x930 mm/slub.c:3437 >> __do_kmalloc_node mm/slab_common.c:954 >> __kmalloc_node_track_caller+0x117/0x3d0 mm/slab_common.c:975 >> kmalloc_reserve net/core/skbuff.c:437 >> __alloc_skb+0x27a/0xab0 net/core/skbuff.c:509 >> alloc_skb ./include/linux/skbuff.h:1267 >> nlmsg_new ./include/net/netlink.h:964 >> ip6addrlbl_get+0x490/0x10f0 net/ipv6/addrlabel.c:608 >> rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 >> netlink_rcv_skb+0x299/0x550 net/netlink/af_netlink.c:2540 >> rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:6109 >> netlink_unicast_kernel net/netlink/af_netlink.c:1319 >> netlink_unicast+0x9ab/0xf50 net/netlink/af_netlink.c:1345 >> netlink_sendmsg+0xebc/0x10f0 net/netlink/af_netlink.c:1921 >> ... >> >> This patch ensures that the reserved field is always initialized. >> >> Reported-by: syzbot+3553517af6020c4f2813f1003fe76ef3cbffe98d@syzkaller.appspotmail.com >> Fixes: 2a8cc6c89039 ("[IPV6] ADDRCONF: Support RFC3484 configurable address selection policy table.") >> Signed-off-by: Alexander Potapenko <glider@google.com> >> --- >> net/ipv6/addrlabel.c | 1 + >> 1 file changed, 1 insertion(+) >> > > Reviewed-by: David Ahern <dsahern@kernel.org> > > I see the command but can't find the corresponding bug. The email is sent to syzbot+HASH@syzkaller.appspotmail.com address but the HASH does not correspond to any known bug. Please double check the address.
Hello: This patch was applied to netdev/net.git (master) by David S. Miller <davem@davemloft.net>: On Fri, 4 Nov 2022 11:32:16 +0100 you wrote: > When copying a `struct ifaddrlblmsg` to the network, __ifal_reserved > remained uninitialized, resulting in a 1-byte infoleak: > > BUG: KMSAN: kernel-network-infoleak in __netdev_start_xmit ./include/linux/netdevice.h:4841 > __netdev_start_xmit ./include/linux/netdevice.h:4841 > netdev_start_xmit ./include/linux/netdevice.h:4857 > xmit_one net/core/dev.c:3590 > dev_hard_start_xmit+0x1dc/0x800 net/core/dev.c:3606 > __dev_queue_xmit+0x17e8/0x4350 net/core/dev.c:4256 > dev_queue_xmit ./include/linux/netdevice.h:3009 > __netlink_deliver_tap_skb net/netlink/af_netlink.c:307 > __netlink_deliver_tap+0x728/0xad0 net/netlink/af_netlink.c:325 > netlink_deliver_tap net/netlink/af_netlink.c:338 > __netlink_sendskb net/netlink/af_netlink.c:1263 > netlink_sendskb+0x1d9/0x200 net/netlink/af_netlink.c:1272 > netlink_unicast+0x56d/0xf50 net/netlink/af_netlink.c:1360 > nlmsg_unicast ./include/net/netlink.h:1061 > rtnl_unicast+0x5a/0x80 net/core/rtnetlink.c:758 > ip6addrlbl_get+0xfad/0x10f0 net/ipv6/addrlabel.c:628 > rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 > ... > Uninit was created at: > slab_post_alloc_hook+0x118/0xb00 mm/slab.h:742 > slab_alloc_node mm/slub.c:3398 > __kmem_cache_alloc_node+0x4f2/0x930 mm/slub.c:3437 > __do_kmalloc_node mm/slab_common.c:954 > __kmalloc_node_track_caller+0x117/0x3d0 mm/slab_common.c:975 > kmalloc_reserve net/core/skbuff.c:437 > __alloc_skb+0x27a/0xab0 net/core/skbuff.c:509 > alloc_skb ./include/linux/skbuff.h:1267 > nlmsg_new ./include/net/netlink.h:964 > ip6addrlbl_get+0x490/0x10f0 net/ipv6/addrlabel.c:608 > rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 > netlink_rcv_skb+0x299/0x550 net/netlink/af_netlink.c:2540 > rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:6109 > netlink_unicast_kernel net/netlink/af_netlink.c:1319 > netlink_unicast+0x9ab/0xf50 net/netlink/af_netlink.c:1345 > netlink_sendmsg+0xebc/0x10f0 net/netlink/af_netlink.c:1921 > ... > > [...] Here is the summary with links: - ipv6: addrlabel: fix infoleak when sending struct ifaddrlblmsg to network https://git.kernel.org/netdev/net/c/c23fb2c82267 You are awesome, thank you!
diff --git a/net/ipv6/addrlabel.c b/net/ipv6/addrlabel.c index 8a22486cf2702..17ac45aa7194c 100644 --- a/net/ipv6/addrlabel.c +++ b/net/ipv6/addrlabel.c @@ -437,6 +437,7 @@ static void ip6addrlbl_putmsg(struct nlmsghdr *nlh, { struct ifaddrlblmsg *ifal = nlmsg_data(nlh); ifal->ifal_family = AF_INET6; + ifal->__ifal_reserved = 0; ifal->ifal_prefixlen = prefixlen; ifal->ifal_flags = 0; ifal->ifal_index = ifindex;
When copying a `struct ifaddrlblmsg` to the network, __ifal_reserved remained uninitialized, resulting in a 1-byte infoleak: BUG: KMSAN: kernel-network-infoleak in __netdev_start_xmit ./include/linux/netdevice.h:4841 __netdev_start_xmit ./include/linux/netdevice.h:4841 netdev_start_xmit ./include/linux/netdevice.h:4857 xmit_one net/core/dev.c:3590 dev_hard_start_xmit+0x1dc/0x800 net/core/dev.c:3606 __dev_queue_xmit+0x17e8/0x4350 net/core/dev.c:4256 dev_queue_xmit ./include/linux/netdevice.h:3009 __netlink_deliver_tap_skb net/netlink/af_netlink.c:307 __netlink_deliver_tap+0x728/0xad0 net/netlink/af_netlink.c:325 netlink_deliver_tap net/netlink/af_netlink.c:338 __netlink_sendskb net/netlink/af_netlink.c:1263 netlink_sendskb+0x1d9/0x200 net/netlink/af_netlink.c:1272 netlink_unicast+0x56d/0xf50 net/netlink/af_netlink.c:1360 nlmsg_unicast ./include/net/netlink.h:1061 rtnl_unicast+0x5a/0x80 net/core/rtnetlink.c:758 ip6addrlbl_get+0xfad/0x10f0 net/ipv6/addrlabel.c:628 rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 ... Uninit was created at: slab_post_alloc_hook+0x118/0xb00 mm/slab.h:742 slab_alloc_node mm/slub.c:3398 __kmem_cache_alloc_node+0x4f2/0x930 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:954 __kmalloc_node_track_caller+0x117/0x3d0 mm/slab_common.c:975 kmalloc_reserve net/core/skbuff.c:437 __alloc_skb+0x27a/0xab0 net/core/skbuff.c:509 alloc_skb ./include/linux/skbuff.h:1267 nlmsg_new ./include/net/netlink.h:964 ip6addrlbl_get+0x490/0x10f0 net/ipv6/addrlabel.c:608 rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 netlink_rcv_skb+0x299/0x550 net/netlink/af_netlink.c:2540 rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:6109 netlink_unicast_kernel net/netlink/af_netlink.c:1319 netlink_unicast+0x9ab/0xf50 net/netlink/af_netlink.c:1345 netlink_sendmsg+0xebc/0x10f0 net/netlink/af_netlink.c:1921 ... This patch ensures that the reserved field is always initialized. Reported-by: syzbot+3553517af6020c4f2813f1003fe76ef3cbffe98d@syzkaller.appspotmail.com Fixes: 2a8cc6c89039 ("[IPV6] ADDRCONF: Support RFC3484 configurable address selection policy table.") Signed-off-by: Alexander Potapenko <glider@google.com> --- net/ipv6/addrlabel.c | 1 + 1 file changed, 1 insertion(+)