From 7dd07c143a4b54d050e748bee4b4b9e94a7b1744 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 11 Apr 2018 14:46:00 -0700 Subject: net: validate attribute sizes in neigh_dump_table() Since neigh_dump_table() calls nlmsg_parse() without giving policy constraints, attributes can have arbirary size that we must validate Reported by syzbot/KMSAN : BUG: KMSAN: uninit-value in neigh_master_filtered net/core/neighbour.c:2292 [inline] BUG: KMSAN: uninit-value in neigh_dump_table net/core/neighbour.c:2348 [inline] BUG: KMSAN: uninit-value in neigh_dump_info+0x1af0/0x2250 net/core/neighbour.c:2438 CPU: 1 PID: 3575 Comm: syzkaller268891 Not tainted 4.16.0+ #83 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676 neigh_master_filtered net/core/neighbour.c:2292 [inline] neigh_dump_table net/core/neighbour.c:2348 [inline] neigh_dump_info+0x1af0/0x2250 net/core/neighbour.c:2438 netlink_dump+0x9ad/0x1540 net/netlink/af_netlink.c:2225 __netlink_dump_start+0x1167/0x12a0 net/netlink/af_netlink.c:2322 netlink_dump_start include/linux/netlink.h:214 [inline] rtnetlink_rcv_msg+0x1435/0x1560 net/core/rtnetlink.c:4598 netlink_rcv_skb+0x355/0x5f0 net/netlink/af_netlink.c:2447 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4653 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x1672/0x1750 net/netlink/af_netlink.c:1337 netlink_sendmsg+0x1048/0x1310 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmsg net/socket.c:2080 [inline] SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091 SyS_sendmsg+0x54/0x80 net/socket.c:2087 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x43fed9 RSP: 002b:00007ffddbee2798 EFLAGS: 00000213 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fed9 RDX: 0000000000000000 RSI: 0000000020005000 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 00000000004002c8 R11: 0000000000000213 R12: 0000000000401800 R13: 0000000000401890 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc_node mm/slub.c:2737 [inline] __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:984 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1183 [inline] netlink_sendmsg+0x9a6/0x1310 net/netlink/af_netlink.c:1875 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmsg net/socket.c:2080 [inline] SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091 SyS_sendmsg+0x54/0x80 net/socket.c:2087 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Fixes: 21fdd092acc7 ("net: Add support for filtering neigh dump by master device") Signed-off-by: Eric Dumazet Cc: David Ahern Reported-by: syzbot Acked-by: David Ahern Signed-off-by: David S. Miller --- net/core/neighbour.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'net/core') diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 7b7a14abba28..a8bc02bb339f 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -2323,12 +2323,16 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb, err = nlmsg_parse(nlh, sizeof(struct ndmsg), tb, NDA_MAX, NULL, NULL); if (!err) { - if (tb[NDA_IFINDEX]) + if (tb[NDA_IFINDEX]) { + if (nla_len(tb[NDA_IFINDEX]) != sizeof(u32)) + return -EINVAL; filter_idx = nla_get_u32(tb[NDA_IFINDEX]); - - if (tb[NDA_MASTER]) + } + if (tb[NDA_MASTER]) { + if (nla_len(tb[NDA_MASTER]) != sizeof(u32)) + return -EINVAL; filter_master_idx = nla_get_u32(tb[NDA_MASTER]); - + } if (filter_idx || filter_master_idx) flags |= NLM_F_DUMP_FILTERED; } -- cgit v1.2.3-55-g7522 From 53b76cdf7e8fecec1d09e38aad2f8579882591a8 Mon Sep 17 00:00:00 2001 From: Wolfgang Bumiller Date: Thu, 12 Apr 2018 10:46:55 +0200 Subject: net: fix deadlock while clearing neighbor proxy table When coming from ndisc_netdev_event() in net/ipv6/ndisc.c, neigh_ifdown() is called with &nd_tbl, locking this while clearing the proxy neighbor entries when eg. deleting an interface. Calling the table's pndisc_destructor() with the lock still held, however, can cause a deadlock: When a multicast listener is available an IGMP packet of type ICMPV6_MGM_REDUCTION may be sent out. When reaching ip6_finish_output2(), if no neighbor entry for the target address is found, __neigh_create() is called with &nd_tbl, which it'll want to lock. Move the elements into their own list, then unlock the table and perform the destruction. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199289 Fixes: 6fd6ce2056de ("ipv6: Do not depend on rt->n in ip6_finish_output2().") Signed-off-by: Wolfgang Bumiller Signed-off-by: David S. Miller --- net/core/neighbour.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) (limited to 'net/core') diff --git a/net/core/neighbour.c b/net/core/neighbour.c index a8bc02bb339f..ce519861be59 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -55,7 +55,8 @@ static void neigh_timer_handler(struct timer_list *t); static void __neigh_notify(struct neighbour *n, int type, int flags, u32 pid); static void neigh_update_notify(struct neighbour *neigh, u32 nlmsg_pid); -static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev); +static int pneigh_ifdown_and_unlock(struct neigh_table *tbl, + struct net_device *dev); #ifdef CONFIG_PROC_FS static const struct file_operations neigh_stat_seq_fops; @@ -291,8 +292,7 @@ int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev) { write_lock_bh(&tbl->lock); neigh_flush_dev(tbl, dev); - pneigh_ifdown(tbl, dev); - write_unlock_bh(&tbl->lock); + pneigh_ifdown_and_unlock(tbl, dev); del_timer_sync(&tbl->proxy_timer); pneigh_queue_purge(&tbl->proxy_queue); @@ -681,9 +681,10 @@ int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *pkey, return -ENOENT; } -static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev) +static int pneigh_ifdown_and_unlock(struct neigh_table *tbl, + struct net_device *dev) { - struct pneigh_entry *n, **np; + struct pneigh_entry *n, **np, *freelist = NULL; u32 h; for (h = 0; h <= PNEIGH_HASHMASK; h++) { @@ -691,16 +692,23 @@ static int pneigh_ifdown(struct neigh_table *tbl, struct net_device *dev) while ((n = *np) != NULL) { if (!dev || n->dev == dev) { *np = n->next; - if (tbl->pdestructor) - tbl->pdestructor(n); - if (n->dev) - dev_put(n->dev); - kfree(n); + n->next = freelist; + freelist = n; continue; } np = &n->next; } } + write_unlock_bh(&tbl->lock); + while ((n = freelist)) { + freelist = n->next; + n->next = NULL; + if (tbl->pdestructor) + tbl->pdestructor(n); + if (n->dev) + dev_put(n->dev); + kfree(n); + } return -ENOENT; } -- cgit v1.2.3-55-g7522 From 7ce2367254e84753bceb07327aaf5c953cfce117 Mon Sep 17 00:00:00 2001 From: Toshiaki Makita Date: Tue, 17 Apr 2018 18:46:14 +0900 Subject: vlan: Fix reading memory beyond skb->tail in skb_vlan_tagged_multi Syzkaller spotted an old bug which leads to reading skb beyond tail by 4 bytes on vlan tagged packets. This is caused because skb_vlan_tagged_multi() did not check skb_headlen. BUG: KMSAN: uninit-value in eth_type_vlan include/linux/if_vlan.h:283 [inline] BUG: KMSAN: uninit-value in skb_vlan_tagged_multi include/linux/if_vlan.h:656 [inline] BUG: KMSAN: uninit-value in vlan_features_check include/linux/if_vlan.h:672 [inline] BUG: KMSAN: uninit-value in dflt_features_check net/core/dev.c:2949 [inline] BUG: KMSAN: uninit-value in netif_skb_features+0xd1b/0xdc0 net/core/dev.c:3009 CPU: 1 PID: 3582 Comm: syzkaller435149 Not tainted 4.16.0+ #82 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676 eth_type_vlan include/linux/if_vlan.h:283 [inline] skb_vlan_tagged_multi include/linux/if_vlan.h:656 [inline] vlan_features_check include/linux/if_vlan.h:672 [inline] dflt_features_check net/core/dev.c:2949 [inline] netif_skb_features+0xd1b/0xdc0 net/core/dev.c:3009 validate_xmit_skb+0x89/0x1320 net/core/dev.c:3084 __dev_queue_xmit+0x1cb2/0x2b60 net/core/dev.c:3549 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3590 packet_snd net/packet/af_packet.c:2944 [inline] packet_sendmsg+0x7c57/0x8a10 net/packet/af_packet.c:2969 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] sock_write_iter+0x3b9/0x470 net/socket.c:909 do_iter_readv_writev+0x7bb/0x970 include/linux/fs.h:1776 do_iter_write+0x30d/0xd40 fs/read_write.c:932 vfs_writev fs/read_write.c:977 [inline] do_writev+0x3c9/0x830 fs/read_write.c:1012 SYSC_writev+0x9b/0xb0 fs/read_write.c:1085 SyS_writev+0x56/0x80 fs/read_write.c:1082 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x43ffa9 RSP: 002b:00007fff2cff3948 EFLAGS: 00000217 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ffa9 RDX: 0000000000000001 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00000000006cb018 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000217 R12: 00000000004018d0 R13: 0000000000401960 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc_node mm/slub.c:2737 [inline] __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:984 [inline] alloc_skb_with_frags+0x1d4/0xb20 net/core/skbuff.c:5234 sock_alloc_send_pskb+0xb56/0x1190 net/core/sock.c:2085 packet_alloc_skb net/packet/af_packet.c:2803 [inline] packet_snd net/packet/af_packet.c:2894 [inline] packet_sendmsg+0x6444/0x8a10 net/packet/af_packet.c:2969 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] sock_write_iter+0x3b9/0x470 net/socket.c:909 do_iter_readv_writev+0x7bb/0x970 include/linux/fs.h:1776 do_iter_write+0x30d/0xd40 fs/read_write.c:932 vfs_writev fs/read_write.c:977 [inline] do_writev+0x3c9/0x830 fs/read_write.c:1012 SYSC_writev+0x9b/0xb0 fs/read_write.c:1085 SyS_writev+0x56/0x80 fs/read_write.c:1082 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Fixes: 58e998c6d239 ("offloading: Force software GSO for multiple vlan tags.") Reported-and-tested-by: syzbot+0bbe42c764feafa82c5a@syzkaller.appspotmail.com Signed-off-by: Toshiaki Makita Signed-off-by: David S. Miller --- include/linux/if_vlan.h | 7 +++++-- net/core/dev.c | 2 +- 2 files changed, 6 insertions(+), 3 deletions(-) (limited to 'net/core') diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h index d11f41d5269f..78a5a90b4267 100644 --- a/include/linux/if_vlan.h +++ b/include/linux/if_vlan.h @@ -663,7 +663,7 @@ static inline bool skb_vlan_tagged(const struct sk_buff *skb) * Returns true if the skb is tagged with multiple vlan headers, regardless * of whether it is hardware accelerated or not. */ -static inline bool skb_vlan_tagged_multi(const struct sk_buff *skb) +static inline bool skb_vlan_tagged_multi(struct sk_buff *skb) { __be16 protocol = skb->protocol; @@ -673,6 +673,9 @@ static inline bool skb_vlan_tagged_multi(const struct sk_buff *skb) if (likely(!eth_type_vlan(protocol))) return false; + if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN))) + return false; + veh = (struct vlan_ethhdr *)skb->data; protocol = veh->h_vlan_encapsulated_proto; } @@ -690,7 +693,7 @@ static inline bool skb_vlan_tagged_multi(const struct sk_buff *skb) * * Returns features without unsafe ones if the skb has multiple tags. */ -static inline netdev_features_t vlan_features_check(const struct sk_buff *skb, +static inline netdev_features_t vlan_features_check(struct sk_buff *skb, netdev_features_t features) { if (skb_vlan_tagged_multi(skb)) { diff --git a/net/core/dev.c b/net/core/dev.c index 969462ebb296..af0558b00c6c 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2969,7 +2969,7 @@ netdev_features_t passthru_features_check(struct sk_buff *skb, } EXPORT_SYMBOL(passthru_features_check); -static netdev_features_t dflt_features_check(const struct sk_buff *skb, +static netdev_features_t dflt_features_check(struct sk_buff *skb, struct net_device *dev, netdev_features_t features) { -- cgit v1.2.3-55-g7522 From bb9aaaa1849eed763c6b7f20227a8a03300d4421 Mon Sep 17 00:00:00 2001 From: sunlianwen Date: Wed, 18 Apr 2018 09:22:39 +0800 Subject: net: change the comment of dev_mc_init The comment of dev_mc_init() is wrong. which use dev_mc_flush instead of dev_mc_init. Signed-off-by: Lianwen Sun --- net/core/dev_addr_lists.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core') diff --git a/net/core/dev_addr_lists.c b/net/core/dev_addr_lists.c index e3e6a3e2ca22..d884d8f5f0e5 100644 --- a/net/core/dev_addr_lists.c +++ b/net/core/dev_addr_lists.c @@ -839,7 +839,7 @@ void dev_mc_flush(struct net_device *dev) EXPORT_SYMBOL(dev_mc_flush); /** - * dev_mc_flush - Init multicast address list + * dev_mc_init - Init multicast address list * @dev: device * * Init multicast address list. -- cgit v1.2.3-55-g7522