diff options
Diffstat (limited to '0001-ipv6-Prevent-overrun-when-parsing-v6-header-options.patch')
| -rw-r--r-- | 0001-ipv6-Prevent-overrun-when-parsing-v6-header-options.patch | 231 |
1 files changed, 0 insertions, 231 deletions
diff --git a/0001-ipv6-Prevent-overrun-when-parsing-v6-header-options.patch b/0001-ipv6-Prevent-overrun-when-parsing-v6-header-options.patch deleted file mode 100644 index b388a6910..000000000 --- a/0001-ipv6-Prevent-overrun-when-parsing-v6-header-options.patch +++ /dev/null @@ -1,231 +0,0 @@ -From 2423496af35d94a87156b063ea5cedffc10a70a1 Mon Sep 17 00:00:00 2001 -From: Craig Gallek <kraig@google.com> -Date: Tue, 16 May 2017 14:36:23 -0400 -Subject: [PATCH] ipv6: Prevent overrun when parsing v6 header options - -The KASAN warning repoted below was discovered with a syzkaller -program. The reproducer is basically: - int s = socket(AF_INET6, SOCK_RAW, NEXTHDR_HOP); - send(s, &one_byte_of_data, 1, MSG_MORE); - send(s, &more_than_mtu_bytes_data, 2000, 0); - -The socket() call sets the nexthdr field of the v6 header to -NEXTHDR_HOP, the first send call primes the payload with a non zero -byte of data, and the second send call triggers the fragmentation path. - -The fragmentation code tries to parse the header options in order -to figure out where to insert the fragment option. Since nexthdr points -to an invalid option, the calculation of the size of the network header -can made to be much larger than the linear section of the skb and data -is read outside of it. - -This fix makes ip6_find_1stfrag return an error if it detects -running out-of-bounds. - -[ 42.361487] ================================================================== -[ 42.364412] BUG: KASAN: slab-out-of-bounds in ip6_fragment+0x11c8/0x3730 -[ 42.365471] Read of size 840 at addr ffff88000969e798 by task ip6_fragment-oo/3789 -[ 42.366469] -[ 42.366696] CPU: 1 PID: 3789 Comm: ip6_fragment-oo Not tainted 4.11.0+ #41 -[ 42.367628] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014 -[ 42.368824] Call Trace: -[ 42.369183] dump_stack+0xb3/0x10b -[ 42.369664] print_address_description+0x73/0x290 -[ 42.370325] kasan_report+0x252/0x370 -[ 42.370839] ? ip6_fragment+0x11c8/0x3730 -[ 42.371396] check_memory_region+0x13c/0x1a0 -[ 42.371978] memcpy+0x23/0x50 -[ 42.372395] ip6_fragment+0x11c8/0x3730 -[ 42.372920] ? nf_ct_expect_unregister_notifier+0x110/0x110 -[ 42.373681] ? ip6_copy_metadata+0x7f0/0x7f0 -[ 42.374263] ? ip6_forward+0x2e30/0x2e30 -[ 42.374803] ip6_finish_output+0x584/0x990 -[ 42.375350] ip6_output+0x1b7/0x690 -[ 42.375836] ? ip6_finish_output+0x990/0x990 -[ 42.376411] ? ip6_fragment+0x3730/0x3730 -[ 42.376968] ip6_local_out+0x95/0x160 -[ 42.377471] ip6_send_skb+0xa1/0x330 -[ 42.377969] ip6_push_pending_frames+0xb3/0xe0 -[ 42.378589] rawv6_sendmsg+0x2051/0x2db0 -[ 42.379129] ? rawv6_bind+0x8b0/0x8b0 -[ 42.379633] ? _copy_from_user+0x84/0xe0 -[ 42.380193] ? debug_check_no_locks_freed+0x290/0x290 -[ 42.380878] ? ___sys_sendmsg+0x162/0x930 -[ 42.381427] ? rcu_read_lock_sched_held+0xa3/0x120 -[ 42.382074] ? sock_has_perm+0x1f6/0x290 -[ 42.382614] ? ___sys_sendmsg+0x167/0x930 -[ 42.383173] ? lock_downgrade+0x660/0x660 -[ 42.383727] inet_sendmsg+0x123/0x500 -[ 42.384226] ? inet_sendmsg+0x123/0x500 -[ 42.384748] ? inet_recvmsg+0x540/0x540 -[ 42.385263] sock_sendmsg+0xca/0x110 -[ 42.385758] SYSC_sendto+0x217/0x380 -[ 42.386249] ? SYSC_connect+0x310/0x310 -[ 42.386783] ? __might_fault+0x110/0x1d0 -[ 42.387324] ? lock_downgrade+0x660/0x660 -[ 42.387880] ? __fget_light+0xa1/0x1f0 -[ 42.388403] ? __fdget+0x18/0x20 -[ 42.388851] ? sock_common_setsockopt+0x95/0xd0 -[ 42.389472] ? SyS_setsockopt+0x17f/0x260 -[ 42.390021] ? entry_SYSCALL_64_fastpath+0x5/0xbe -[ 42.390650] SyS_sendto+0x40/0x50 -[ 42.391103] entry_SYSCALL_64_fastpath+0x1f/0xbe -[ 42.391731] RIP: 0033:0x7fbbb711e383 -[ 42.392217] RSP: 002b:00007ffff4d34f28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c -[ 42.393235] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbbb711e383 -[ 42.394195] RDX: 0000000000001000 RSI: 00007ffff4d34f60 RDI: 0000000000000003 -[ 42.395145] RBP: 0000000000000046 R08: 00007ffff4d34f40 R09: 0000000000000018 -[ 42.396056] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400aad -[ 42.396598] R13: 0000000000000066 R14: 00007ffff4d34ee0 R15: 00007fbbb717af00 -[ 42.397257] -[ 42.397411] Allocated by task 3789: -[ 42.397702] save_stack_trace+0x16/0x20 -[ 42.398005] save_stack+0x46/0xd0 -[ 42.398267] kasan_kmalloc+0xad/0xe0 -[ 42.398548] kasan_slab_alloc+0x12/0x20 -[ 42.398848] __kmalloc_node_track_caller+0xcb/0x380 -[ 42.399224] __kmalloc_reserve.isra.32+0x41/0xe0 -[ 42.399654] __alloc_skb+0xf8/0x580 -[ 42.400003] sock_wmalloc+0xab/0xf0 -[ 42.400346] __ip6_append_data.isra.41+0x2472/0x33d0 -[ 42.400813] ip6_append_data+0x1a8/0x2f0 -[ 42.401122] rawv6_sendmsg+0x11ee/0x2db0 -[ 42.401505] inet_sendmsg+0x123/0x500 -[ 42.401860] sock_sendmsg+0xca/0x110 -[ 42.402209] ___sys_sendmsg+0x7cb/0x930 -[ 42.402582] __sys_sendmsg+0xd9/0x190 -[ 42.402941] SyS_sendmsg+0x2d/0x50 -[ 42.403273] entry_SYSCALL_64_fastpath+0x1f/0xbe -[ 42.403718] -[ 42.403871] Freed by task 1794: -[ 42.404146] save_stack_trace+0x16/0x20 -[ 42.404515] save_stack+0x46/0xd0 -[ 42.404827] kasan_slab_free+0x72/0xc0 -[ 42.405167] kfree+0xe8/0x2b0 -[ 42.405462] skb_free_head+0x74/0xb0 -[ 42.405806] skb_release_data+0x30e/0x3a0 -[ 42.406198] skb_release_all+0x4a/0x60 -[ 42.406563] consume_skb+0x113/0x2e0 -[ 42.406910] skb_free_datagram+0x1a/0xe0 -[ 42.407288] netlink_recvmsg+0x60d/0xe40 -[ 42.407667] sock_recvmsg+0xd7/0x110 -[ 42.408022] ___sys_recvmsg+0x25c/0x580 -[ 42.408395] __sys_recvmsg+0xd6/0x190 -[ 42.408753] SyS_recvmsg+0x2d/0x50 -[ 42.409086] entry_SYSCALL_64_fastpath+0x1f/0xbe -[ 42.409513] -[ 42.409665] The buggy address belongs to the object at ffff88000969e780 -[ 42.409665] which belongs to the cache kmalloc-512 of size 512 -[ 42.410846] The buggy address is located 24 bytes inside of -[ 42.410846] 512-byte region [ffff88000969e780, ffff88000969e980) -[ 42.411941] The buggy address belongs to the page: -[ 42.412405] page:ffffea000025a780 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 -[ 42.413298] flags: 0x100000000008100(slab|head) -[ 42.413729] raw: 0100000000008100 0000000000000000 0000000000000000 00000001800c000c -[ 42.414387] raw: ffffea00002a9500 0000000900000007 ffff88000c401280 0000000000000000 -[ 42.415074] page dumped because: kasan: bad access detected -[ 42.415604] -[ 42.415757] Memory state around the buggy address: -[ 42.416222] ffff88000969e880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 -[ 42.416904] ffff88000969e900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 -[ 42.417591] >ffff88000969e980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc -[ 42.418273] ^ -[ 42.418588] ffff88000969ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb -[ 42.419273] ffff88000969ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb -[ 42.419882] ================================================================== - -Reported-by: Andrey Konovalov <andreyknvl@google.com> -Signed-off-by: Craig Gallek <kraig@google.com> -Signed-off-by: David S. Miller <davem@davemloft.net> ---- - net/ipv6/ip6_offload.c | 2 ++ - net/ipv6/ip6_output.c | 4 ++++ - net/ipv6/output_core.c | 14 ++++++++------ - net/ipv6/udp_offload.c | 2 ++ - 4 files changed, 16 insertions(+), 6 deletions(-) - -diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c -index 93e58a5..eab36ab 100644 ---- a/net/ipv6/ip6_offload.c -+++ b/net/ipv6/ip6_offload.c -@@ -117,6 +117,8 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, - - if (udpfrag) { - unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr); -+ if (unfrag_ip6hlen < 0) -+ return ERR_PTR(unfrag_ip6hlen); - fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen); - fptr->frag_off = htons(offset); - if (skb->next) -diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c -index 58f6288..01deecd 100644 ---- a/net/ipv6/ip6_output.c -+++ b/net/ipv6/ip6_output.c -@@ -598,6 +598,10 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, - u8 *prevhdr, nexthdr = 0; - - hlen = ip6_find_1stfragopt(skb, &prevhdr); -+ if (hlen < 0) { -+ err = hlen; -+ goto fail; -+ } - nexthdr = *prevhdr; - - mtu = ip6_skb_dst_mtu(skb); -diff --git a/net/ipv6/output_core.c b/net/ipv6/output_core.c -index cd42523..e9065b8 100644 ---- a/net/ipv6/output_core.c -+++ b/net/ipv6/output_core.c -@@ -79,14 +79,13 @@ EXPORT_SYMBOL(ipv6_select_ident); - int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) - { - u16 offset = sizeof(struct ipv6hdr); -- struct ipv6_opt_hdr *exthdr = -- (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); - unsigned int packet_len = skb_tail_pointer(skb) - - skb_network_header(skb); - int found_rhdr = 0; - *nexthdr = &ipv6_hdr(skb)->nexthdr; - -- while (offset + 1 <= packet_len) { -+ while (offset <= packet_len) { -+ struct ipv6_opt_hdr *exthdr; - - switch (**nexthdr) { - -@@ -107,13 +106,16 @@ int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) - return offset; - } - -- offset += ipv6_optlen(exthdr); -- *nexthdr = &exthdr->nexthdr; -+ if (offset + sizeof(struct ipv6_opt_hdr) > packet_len) -+ return -EINVAL; -+ - exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + - offset); -+ offset += ipv6_optlen(exthdr); -+ *nexthdr = &exthdr->nexthdr; - } - -- return offset; -+ return -EINVAL; - } - EXPORT_SYMBOL(ip6_find_1stfragopt); - -diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c -index ac858c4..b348cff 100644 ---- a/net/ipv6/udp_offload.c -+++ b/net/ipv6/udp_offload.c -@@ -91,6 +91,8 @@ static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, - * bytes to insert fragment header. - */ - unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr); -+ if (unfrag_ip6hlen < 0) -+ return ERR_PTR(unfrag_ip6hlen); - nexthdr = *prevhdr; - *prevhdr = NEXTHDR_FRAGMENT; - unfrag_len = (skb_network_header(skb) - skb_mac_header(skb)) + --- -2.9.4 - |