* [PATCH net-next] net: metrics: add proper netlink validation
@ 2018-06-04 23:46 Eric Dumazet
2018-06-04 23:54 ` David Ahern
2018-06-05 5:48 ` Eric Dumazet
0 siblings, 2 replies; 4+ messages in thread
From: Eric Dumazet @ 2018-06-04 23:46 UTC (permalink / raw)
To: David S . Miller; +Cc: netdev, Eric Dumazet, Eric Dumazet, David Ahern
Before using nla_get_u32(), better make sure the attribute
is of the proper size.
Code recently was changed, but bug has been there from beginning
of git.
BUG: KMSAN: uninit-value in rtnetlink_put_metrics+0x553/0x960 net/core/rtnetlink.c:746
CPU: 1 PID: 14139 Comm: syz-executor6 Not tainted 4.17.0-rc5+ #103
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x185/0x1d0 lib/dump_stack.c:113
kmsan_report+0x149/0x260 mm/kmsan/kmsan.c:1084
__msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:686
rtnetlink_put_metrics+0x553/0x960 net/core/rtnetlink.c:746
fib_dump_info+0xc42/0x2190 net/ipv4/fib_semantics.c:1361
rtmsg_fib+0x65f/0x8c0 net/ipv4/fib_semantics.c:419
fib_table_insert+0x2314/0x2b50 net/ipv4/fib_trie.c:1287
inet_rtm_newroute+0x210/0x340 net/ipv4/fib_frontend.c:779
rtnetlink_rcv_msg+0xa32/0x1560 net/core/rtnetlink.c:4646
netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2448
rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4664
netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
netlink_unicast+0x1678/0x1750 net/netlink/af_netlink.c:1336
netlink_sendmsg+0x104f/0x1350 net/netlink/af_netlink.c:1901
sock_sendmsg_nosec net/socket.c:629 [inline]
sock_sendmsg net/socket.c:639 [inline]
___sys_sendmsg+0xec0/0x1310 net/socket.c:2117
__sys_sendmsg net/socket.c:2155 [inline]
__do_sys_sendmsg net/socket.c:2164 [inline]
__se_sys_sendmsg net/socket.c:2162 [inline]
__x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455a09
RSP: 002b:00007faae5fd8c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007faae5fd96d4 RCX: 0000000000455a09
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000005d0 R14: 00000000006fdc20 R15: 0000000000000000
Uninit was stored to memory at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
kmsan_save_stack mm/kmsan/kmsan.c:294 [inline]
kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:685
__msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:529
fib_convert_metrics net/ipv4/fib_semantics.c:1056 [inline]
fib_create_info+0x2d46/0x9dc0 net/ipv4/fib_semantics.c:1150
fib_table_insert+0x3e4/0x2b50 net/ipv4/fib_trie.c:1146
inet_rtm_newroute+0x210/0x340 net/ipv4/fib_frontend.c:779
rtnetlink_rcv_msg+0xa32/0x1560 net/core/rtnetlink.c:4646
netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2448
rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4664
netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
netlink_unicast+0x1678/0x1750 net/netlink/af_netlink.c:1336
netlink_sendmsg+0x104f/0x1350 net/netlink/af_netlink.c:1901
sock_sendmsg_nosec net/socket.c:629 [inline]
sock_sendmsg net/socket.c:639 [inline]
___sys_sendmsg+0xec0/0x1310 net/socket.c:2117
__sys_sendmsg net/socket.c:2155 [inline]
__do_sys_sendmsg net/socket.c:2164 [inline]
__se_sys_sendmsg net/socket.c:2162 [inline]
__x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Uninit was created at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:189
kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:315
kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan.c:322
slab_post_alloc_hook mm/slab.h:446 [inline]
slab_alloc_node mm/slub.c:2753 [inline]
__kmalloc_node_track_caller+0xb32/0x11b0 mm/slub.c:4395
__kmalloc_reserve net/core/skbuff.c:138 [inline]
__alloc_skb+0x2cb/0x9e0 net/core/skbuff.c:206
alloc_skb include/linux/skbuff.h:988 [inline]
netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
netlink_sendmsg+0x76e/0x1350 net/netlink/af_netlink.c:1876
sock_sendmsg_nosec net/socket.c:629 [inline]
sock_sendmsg net/socket.c:639 [inline]
___sys_sendmsg+0xec0/0x1310 net/socket.c:2117
__sys_sendmsg net/socket.c:2155 [inline]
__do_sys_sendmsg net/socket.c:2164 [inline]
__se_sys_sendmsg net/socket.c:2162 [inline]
__x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: a919525ad832 ("net: Move fib_convert_metrics to metrics file")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: David Ahern <dsahern@gmail.com>
---
net/ipv4/fib_semantics.c | 2 ++
net/ipv4/metrics.c | 2 ++
2 files changed, 4 insertions(+)
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 6608db23f54b6afdac0455650b47d64b1b22b255..9a890be8a0265edb78da225a82e2cac120f2150f 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -717,6 +717,8 @@ bool fib_metrics_match(struct fib_config *cfg, struct fib_info *fi)
nla_strlcpy(tmp, nla, sizeof(tmp));
val = tcp_ca_get_key_by_name(fi->fib_net, tmp, &ecn_ca);
} else {
+ if (nla_len(nla) != sizeof(u32)
+ return false;
val = nla_get_u32(nla);
}
diff --git a/net/ipv4/metrics.c b/net/ipv4/metrics.c
index 5121c6475e6b0e9a9a158d4cee473f52cd4d8efe..04311f7067e2e9e3dafb89aa4f8e30dab0fde854 100644
--- a/net/ipv4/metrics.c
+++ b/net/ipv4/metrics.c
@@ -32,6 +32,8 @@ int ip_metrics_convert(struct net *net, struct nlattr *fc_mx, int fc_mx_len,
if (val == TCP_CA_UNSPEC)
return -EINVAL;
} else {
+ if (nla_len(nla) != sizeof(u32))
+ return -EINVAL;
val = nla_get_u32(nla);
}
if (type == RTAX_ADVMSS && val > 65535 - 40)
--
2.17.1.1185.g55be947832-goog
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH net-next] net: metrics: add proper netlink validation
2018-06-04 23:46 [PATCH net-next] net: metrics: add proper netlink validation Eric Dumazet
@ 2018-06-04 23:54 ` David Ahern
2018-06-04 23:58 ` Eric Dumazet
2018-06-05 5:48 ` Eric Dumazet
1 sibling, 1 reply; 4+ messages in thread
From: David Ahern @ 2018-06-04 23:54 UTC (permalink / raw)
To: Eric Dumazet, David S . Miller; +Cc: netdev, Eric Dumazet
On 6/4/18 4:46 PM, Eric Dumazet wrote:
> Before using nla_get_u32(), better make sure the attribute
> is of the proper size.
>
> Code recently was changed, but bug has been there from beginning
> of git.
>
...
>
> Fixes: a919525ad832 ("net: Move fib_convert_metrics to metrics file")
That commit just moved the code from 1 file to another. The previous
commit id is 6cf9dfd3bd62e, but it just moved code to a helper. The
originating commit id for the ip_metrics_convert bug is:
ea697639992d9 ("net: tcp: add RTAX_CC_ALGO fib handling")
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: syzbot <syzkaller@googlegroups.com>
> Cc: David Ahern <dsahern@gmail.com>
> ---
> net/ipv4/fib_semantics.c | 2 ++
> net/ipv4/metrics.c | 2 ++
> 2 files changed, 4 insertions(+)
>
> diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
> index 6608db23f54b6afdac0455650b47d64b1b22b255..9a890be8a0265edb78da225a82e2cac120f2150f 100644
> --- a/net/ipv4/fib_semantics.c
> +++ b/net/ipv4/fib_semantics.c
> @@ -717,6 +717,8 @@ bool fib_metrics_match(struct fib_config *cfg, struct fib_info *fi)
> nla_strlcpy(tmp, nla, sizeof(tmp));
> val = tcp_ca_get_key_by_name(fi->fib_net, tmp, &ecn_ca);
> } else {
> + if (nla_len(nla) != sizeof(u32)
> + return false;
> val = nla_get_u32(nla);
> }
>
> diff --git a/net/ipv4/metrics.c b/net/ipv4/metrics.c
> index 5121c6475e6b0e9a9a158d4cee473f52cd4d8efe..04311f7067e2e9e3dafb89aa4f8e30dab0fde854 100644
> --- a/net/ipv4/metrics.c
> +++ b/net/ipv4/metrics.c
> @@ -32,6 +32,8 @@ int ip_metrics_convert(struct net *net, struct nlattr *fc_mx, int fc_mx_len,
> if (val == TCP_CA_UNSPEC)
> return -EINVAL;
> } else {
> + if (nla_len(nla) != sizeof(u32))
> + return -EINVAL;
> val = nla_get_u32(nla);
> }
> if (type == RTAX_ADVMSS && val > 65535 - 40)
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH net-next] net: metrics: add proper netlink validation
2018-06-04 23:54 ` David Ahern
@ 2018-06-04 23:58 ` Eric Dumazet
0 siblings, 0 replies; 4+ messages in thread
From: Eric Dumazet @ 2018-06-04 23:58 UTC (permalink / raw)
To: David Ahern, Eric Dumazet, David S . Miller; +Cc: netdev
On 06/04/2018 04:54 PM, David Ahern wrote:
> On 6/4/18 4:46 PM, Eric Dumazet wrote:
>> Before using nla_get_u32(), better make sure the attribute
>> is of the proper size.
>>
>> Code recently was changed, but bug has been there from beginning
>> of git.
>>
> ...
>>
>> Fixes: a919525ad832 ("net: Move fib_convert_metrics to metrics file")
>
> That commit just moved the code from 1 file to another. The previous
> commit id is 6cf9dfd3bd62e, but it just moved code to a helper. The
> originating commit id for the ip_metrics_convert bug is:
>
Please read what I wrote.
I simply wanted to warn stable teams that your this patch is based on recent tree,
but bug has been there forever.
The Fixes: tag might help them to cook proper backports, thats is all.
A Fixes: tag does not blame the code, it simply gives some hints.
> ea697639992d9 ("net: tcp: add RTAX_CC_ALGO fib handling")
>
This patch has not added any bug, it was there already.
I can put a (long) list of tags, but ultimately the bug has been there forever.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH net-next] net: metrics: add proper netlink validation
2018-06-04 23:46 [PATCH net-next] net: metrics: add proper netlink validation Eric Dumazet
2018-06-04 23:54 ` David Ahern
@ 2018-06-05 5:48 ` Eric Dumazet
1 sibling, 0 replies; 4+ messages in thread
From: Eric Dumazet @ 2018-06-05 5:48 UTC (permalink / raw)
To: Eric Dumazet, David S . Miller; +Cc: netdev, Eric Dumazet, David Ahern
On 06/04/2018 04:46 PM, Eric Dumazet wrote:
> Before using nla_get_u32(), better make sure the attribute
> is of the proper size.
>
>
> Fixes: a919525ad832 ("net: Move fib_convert_metrics to metrics file")
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: syzbot <syzkaller@googlegroups.com>
> Cc: David Ahern <dsahern@gmail.com>
> ---
> net/ipv4/fib_semantics.c | 2 ++
> net/ipv4/metrics.c | 2 ++
> 2 files changed, 4 insertions(+)
>
> diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
> index 6608db23f54b6afdac0455650b47d64b1b22b255..9a890be8a0265edb78da225a82e2cac120f2150f 100644
> --- a/net/ipv4/fib_semantics.c
> +++ b/net/ipv4/fib_semantics.c
> @@ -717,6 +717,8 @@ bool fib_metrics_match(struct fib_config *cfg, struct fib_info *fi)
> nla_strlcpy(tmp, nla, sizeof(tmp));
> val = tcp_ca_get_key_by_name(fi->fib_net, tmp, &ecn_ca);
> } else {
> + if (nla_len(nla) != sizeof(u32)
Oh well, stupid typo.
> + return false;
> val = nla_get_u32(nla);
I will send a V2.
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2018-06-05 5:48 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2018-06-04 23:46 [PATCH net-next] net: metrics: add proper netlink validation Eric Dumazet
2018-06-04 23:54 ` David Ahern
2018-06-04 23:58 ` Eric Dumazet
2018-06-05 5:48 ` Eric Dumazet
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