[ upstream commit 290af86629b25ffd1ed6232c4e9107da031705cb ]
The BPF interpreter has been used as part of the spectre 2 attack CVE-2017-5715.
A quote from goolge project zero blog:
"At this point, it would normally be necessary to locate gadgets in
the host kernel code that can be used to actually leak data by reading
from an attacker-controlled location, shifting and masking the result
appropriately and then using the result of that as offset to an
attacker-controlled address for a load. But piecing gadgets together
and figuring out which ones work in a speculation context seems annoying.
So instead, we decided to use the eBPF interpreter, which is built into
the host kernel - while there is no legitimate way to invoke it from inside
a VM, the presence of the code in the host kernel's text section is sufficient
to make it usable for the attack, just like with ordinary ROP gadgets."
To make attacker job harder introduce BPF_JIT_ALWAYS_ON config
option that removes interpreter from the kernel in favor of JIT-only mode.
So far eBPF JIT is supported by:
x64, arm64, arm32, sparc64, s390, powerpc64, mips64
The start of JITed program is randomized and code page is marked as read-only.
In addition "constant blinding" can be turned on with net.core.bpf_jit_harden
v2->v3:
- move __bpf_prog_ret0 under ifdef (Daniel)
v1->v2:
- fix init order, test_bpf and cBPF (Daniel's feedback)
- fix offloaded bpf (Jakub's feedback)
- add 'return 0' dummy in case something can invoke prog->bpf_func
- retarget bpf tree. For bpf-next the patch would need one extra hunk.
It will be sent when the trees are merged back to net-next
Considered doing:
int bpf_jit_enable __read_mostly = BPF_EBPF_JIT_DEFAULT;
but it seems better to land the patch as-is and in bpf-next remove
bpf_jit_enable global variable from all JITs, consolidate in one place
and remove this jit_init() function.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d0c081b49137cd3200f2023c0875723be66e7ce5 ]
syzbot reported yet another crash [1] that is caused by
insufficient validation of DODGY packets.
Two bugs are happening here to trigger the crash.
1) Flow dissection leaves with incorrect thoff field.
2) skb_probe_transport_header() sets transport header to this invalid
thoff, even if pointing after skb valid data.
3) qdisc_pkt_len_init() reads out-of-bound data because it
trusts tcp_hdrlen(skb)
Possible fixes :
- Full flow dissector validation before injecting bad DODGY packets in
the stack.
This approach was attempted here : https://patchwork.ozlabs.org/patch/
861874/
- Have more robust functions in the core.
This might be needed anyway for stable versions.
This patch fixes the flow dissection issue.
[1]
CPU: 1 PID: 3144 Comm: syzkaller271204 Not tainted 4.15.0-rc4-mm1+ #49
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+0x194/0x257 lib/dump_stack.c:53
print_address_description+0x73/0x250 mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:355 [inline]
kasan_report+0x23b/0x360 mm/kasan/report.c:413
__asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:432
__tcp_hdrlen include/linux/tcp.h:35 [inline]
tcp_hdrlen include/linux/tcp.h:40 [inline]
qdisc_pkt_len_init net/core/dev.c:3160 [inline]
__dev_queue_xmit+0x20d3/0x2200 net/core/dev.c:3465
dev_queue_xmit+0x17/0x20 net/core/dev.c:3554
packet_snd net/packet/af_packet.c:2943 [inline]
packet_sendmsg+0x3ad5/0x60a0 net/packet/af_packet.c:2968
sock_sendmsg_nosec net/socket.c:628 [inline]
sock_sendmsg+0xca/0x110 net/socket.c:638
sock_write_iter+0x31a/0x5d0 net/socket.c:907
call_write_iter include/linux/fs.h:1776 [inline]
new_sync_write fs/read_write.c:469 [inline]
__vfs_write+0x684/0x970 fs/read_write.c:482
vfs_write+0x189/0x510 fs/read_write.c:544
SYSC_write fs/read_write.c:589 [inline]
SyS_write+0xef/0x220 fs/read_write.c:581
entry_SYSCALL_64_fastpath+0x1f/0x96
Fixes: 34fad54c2537 ("net: __skb_flow_dissect() must cap its return value")
Fixes: a6e544b0a8 ("flow_dissector: Jump to exit code in __skb_flow_dissect")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 096b9854c04df86f03b38a97d40b6506e5730919 ]
Use n->primary_key instead of pkey to account for the possibility that a neigh
constructor function may have modified the primary_key value.
Signed-off-by: Jim Westfall <jwestfall@surrealistic.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7c68d1a6b4db9012790af7ac0f0fdc0d2083422a ]
Without proper validation of DODGY packets, we might very well
feed qdisc_pkt_len_init() with invalid GSO packets.
tcp_hdrlen() might access out-of-bound data, so let's use
skb_header_pointer() and proper checks.
Whole story is described in commit d0c081b49137 ("flow_dissector:
properly cap thoff field")
We have the goal of validating DODGY packets earlier in the stack,
so we might very well revert this fix in the future.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jason Wang <jasowang@redhat.com>
Reported-by: syzbot+9da69ebac7dddd804552@syzkaller.appspotmail.com
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b8fd0823e0770c2d5fdbd865bccf0d5e058e5287 ]
Use AF_INET6 instead of AF_INET in IPv6-related code path
Signed-off-by: Andrii Vladyka <tulup@mail.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 35b99dffc3f710cafceee6c8c6ac6a98eb2cb4bf ]
skb_complete_tx_timestamp must ingest the skb it is passed. Call
kfree_skb if the skb cannot be enqueued.
Fixes: b245be1f4d ("net-timestamp: no-payload only sysctl")
Fixes: 9ac25fc06375 ("net: fix socket refcounting in skb_complete_tx_timestamp()")
Reported-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 21b5944350052d2583e82dd59b19a9ba94a007f0 ]
(I can trivially verify that that idr_remove in cleanup_net happens
after the network namespace count has dropped to zero --EWB)
Function get_net_ns_by_id() does not check for net::count
after it has found a peer in netns_ids idr.
It may dereference a peer, after its count has already been
finaly decremented. This leads to double free and memory
corruption:
put_net(peer) rtnl_lock()
atomic_dec_and_test(&peer->count) [count=0] ...
__put_net(peer) get_net_ns_by_id(net, id)
spin_lock(&cleanup_list_lock)
list_add(&net->cleanup_list, &cleanup_list)
spin_unlock(&cleanup_list_lock)
queue_work() peer = idr_find(&net->netns_ids, id)
| get_net(peer) [count=1]
| ...
| (use after final put)
v ...
cleanup_net() ...
spin_lock(&cleanup_list_lock) ...
list_replace_init(&cleanup_list, ..) ...
spin_unlock(&cleanup_list_lock) ...
... ...
... put_net(peer)
... atomic_dec_and_test(&peer->count) [count=0]
... spin_lock(&cleanup_list_lock)
... list_add(&net->cleanup_list, &cleanup_list)
... spin_unlock(&cleanup_list_lock)
... queue_work()
... rtnl_unlock()
rtnl_lock() ...
for_each_net(tmp) { ...
id = __peernet2id(tmp, peer) ...
spin_lock_irq(&tmp->nsid_lock) ...
idr_remove(&tmp->netns_ids, id) ...
... ...
net_drop_ns() ...
net_free(peer) ...
} ...
|
v
cleanup_net()
...
(Second free of peer)
Also, put_net() on the right cpu may reorder with left's cpu
list_replace_init(&cleanup_list, ..), and then cleanup_list
will be corrupted.
Since cleanup_net() is executed in worker thread, while
put_net(peer) can happen everywhere, there should be
enough time for concurrent get_net_ns_by_id() to pick
the peer up, and the race does not seem to be unlikely.
The patch fixes the problem in standard way.
(Also, there is possible problem in peernet2id_alloc(), which requires
check for net::count under nsid_lock and maybe_get_net(peer), but
in current stable kernel it's used under rtnl_lock() and it has to be
safe. Openswitch begun to use peernet2id_alloc(), and possibly it should
be fixed too. While this is not in stable kernel yet, so I'll send
a separate message to netdev@ later).
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Fixes: 0c7aecd4bd "netns: add rtnl cmd to add and get peer netns ids"
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 95f255211396958c718aef8c45e3923b5211ea7b ]
This change basically codifies what I think was already the limitations on
the busy_poll and busy_read sysctl interfaces. We weren't checking the
lower bounds and as such could input negative values. The behavior when
that was used was dependent on the architecture. In order to prevent any
issues with that I am just disabling support for values less than 0 since
this way we don't have to worry about any odd behaviors.
By limiting the sysctl values this way it also makes it consistent with how
we handle the SO_BUSY_POLL socket option since the value appears to be
reported as a signed integer value and negative values are rejected.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 37c343b4f4e70e9dc328ab04903c0ec8d154c1a4 ]
When we notify peers of potential changes, it's also good to update
IGMP memberships. For example, during VM migration, updating IGMP
memberships will redirect existing multicast streams to the VM at the
new location.
Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2b5ec1a5f9738ee7bf8f5ec0526e75e00362c48f ]
When run ipvs in two different network namespace at the same host, and one
ipvs transport network traffic to the other network namespace ipvs.
'ipvs_property' flag will make the second ipvs take no effect. So we should
clear 'ipvs_property' when SKB network namespace changed.
Fixes: 621e84d6f3 ("dev: introduce skb_scrub_packet()")
Signed-off-by: Ye Yin <hustcat@gmail.com>
Signed-off-by: Wei Zhou <chouryzhou@gmail.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0ad646c81b2182f7fa67ec0c8c825e0ee165696d ]
register_netdevice() could fail early when we have an invalid
dev name, in which case ->ndo_uninit() is not called. For tun
device, this is a problem because a timer etc. are already
initialized and it expects ->ndo_uninit() to clean them up.
We could move these initializations into a ->ndo_init() so
that register_netdevice() knows better, however this is still
complicated due to the logic in tun_detach().
Therefore, I choose to just call dev_get_valid_name() before
register_netdevice(), which is quicker and much easier to audit.
And for this specific case, it is already enough.
Fixes: 96442e4242 ("tuntap: choose the txq based on rxq")
Reported-by: Dmitry Alexeev <avekceeb@gmail.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9d538fa60bad4f7b23193c89e843797a1cf71ef3 ]
sk->sk_prot and sk->sk_prot_creator can differ when the app uses
IPV6_ADDRFORM (transforming an IPv6-socket to an IPv4-one).
Which is why sk_prot_creator is there to make sure that sk_prot_free()
does the kmem_cache_free() on the right kmem_cache slab.
Now, if such a socket gets transformed back to a listening socket (using
connect() with AF_UNSPEC) we will allocate an IPv4 tcp_sock through
sk_clone_lock() when a new connection comes in. But sk_prot_creator will
still point to the IPv6 kmem_cache (as everything got copied in
sk_clone_lock()). When freeing, we will thus put this
memory back into the IPv6 kmem_cache although it was allocated in the
IPv4 cache. I have seen memory corruption happening because of this.
With slub-debugging and MEMCG_KMEM enabled this gives the warning
"cache_from_obj: Wrong slab cache. TCPv6 but object is from TCP"
A C-program to trigger this:
void main(void)
{
int fd = socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP);
int new_fd, newest_fd, client_fd;
struct sockaddr_in6 bind_addr;
struct sockaddr_in bind_addr4, client_addr1, client_addr2;
struct sockaddr unsp;
int val;
memset(&bind_addr, 0, sizeof(bind_addr));
bind_addr.sin6_family = AF_INET6;
bind_addr.sin6_port = ntohs(42424);
memset(&client_addr1, 0, sizeof(client_addr1));
client_addr1.sin_family = AF_INET;
client_addr1.sin_port = ntohs(42424);
client_addr1.sin_addr.s_addr = inet_addr("127.0.0.1");
memset(&client_addr2, 0, sizeof(client_addr2));
client_addr2.sin_family = AF_INET;
client_addr2.sin_port = ntohs(42421);
client_addr2.sin_addr.s_addr = inet_addr("127.0.0.1");
memset(&unsp, 0, sizeof(unsp));
unsp.sa_family = AF_UNSPEC;
bind(fd, (struct sockaddr *)&bind_addr, sizeof(bind_addr));
listen(fd, 5);
client_fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
connect(client_fd, (struct sockaddr *)&client_addr1, sizeof(client_addr1));
new_fd = accept(fd, NULL, NULL);
close(fd);
val = AF_INET;
setsockopt(new_fd, SOL_IPV6, IPV6_ADDRFORM, &val, sizeof(val));
connect(new_fd, &unsp, sizeof(unsp));
memset(&bind_addr4, 0, sizeof(bind_addr4));
bind_addr4.sin_family = AF_INET;
bind_addr4.sin_port = ntohs(42421);
bind(new_fd, (struct sockaddr *)&bind_addr4, sizeof(bind_addr4));
listen(new_fd, 5);
client_fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
connect(client_fd, (struct sockaddr *)&client_addr2, sizeof(client_addr2));
newest_fd = accept(new_fd, NULL, NULL);
close(new_fd);
close(client_fd);
close(new_fd);
}
As far as I can see, this bug has been there since the beginning of the
git-days.
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9899886d5e8ec5b343b1efe44f185a0e68dc6454 ]
Added NULL check to make __dev_kfree_skb_irq consistent with kfree
family of functions.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=195289
Signed-off-by: Myungho Jung <mhjungk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8d63bee643f1fb53e472f0e135cae4eb99d62d19 ]
skb_warn_bad_offload triggers a warning when an skb enters the GSO
stack at __skb_gso_segment that does not have CHECKSUM_PARTIAL
checksum offload set.
Commit b2504a5dbef3 ("net: reduce skb_warn_bad_offload() noise")
observed that SKB_GSO_DODGY producers can trigger the check and
that passing those packets through the GSO handlers will fix it
up. But, the software UFO handler will set ip_summed to
CHECKSUM_NONE.
When __skb_gso_segment is called from the receive path, this
triggers the warning again.
Make UFO set CHECKSUM_UNNECESSARY instead of CHECKSUM_NONE. On
Tx these two are equivalent. On Rx, this better matches the
skb state (checksum computed), as CHECKSUM_NONE here means no
checksum computed.
See also this thread for context:
http://patchwork.ozlabs.org/patch/799015/
Fixes: b2504a5dbef3 ("net: reduce skb_warn_bad_offload() noise")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 153711f9421be5dbc973dc57a4109dc9d54c89b1 ]
virtnet_set_mac_address() interprets mac address as struct
sockaddr, but upper layer only allocates dev->addr_len
which is ETH_ALEN + sizeof(sa_family_t) in this case.
We lack a unified definition for mac address, so just fix
the upper layer, this also allows drivers to interpret it
to struct sockaddr freely.
Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 63679112c536289826fec61c917621de95ba2ade ]
The ifr.ifr_name is passed around and assumed to be NULL terminated.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6e7bc478c9a006c701c14476ec9d389a484b4864 upstream.
My recent change missed fact that UFO would perform a complete
UDP checksum before segmenting in frags.
In this case skb->ip_summed is set to CHECKSUM_NONE.
We need to add this valid case to skb_needs_check()
Fixes: b2504a5dbef3 ("net: reduce skb_warn_bad_offload() noise")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b2504a5dbef3305ef41988ad270b0e8ec289331c upstream.
Dmitry reported warnings occurring in __skb_gso_segment() [1]
All SKB_GSO_DODGY producers can allow user space to feed
packets that trigger the current check.
We could prevent them from doing so, rejecting packets, but
this might add regressions to existing programs.
It turns out our SKB_GSO_DODGY handlers properly set up checksum
information that is needed anyway when packets needs to be segmented.
By checking again skb_needs_check() after skb_mac_gso_segment(),
we should remove these pesky warnings, at a very minor cost.
With help from Willem de Bruijn
[1]
WARNING: CPU: 1 PID: 6768 at net/core/dev.c:2439 skb_warn_bad_offload+0x2af/0x390 net/core/dev.c:2434
lo: caps=(0x000000a2803b7c69, 0x0000000000000000) len=138 data_len=0 gso_size=15883 gso_type=4 ip_summed=0
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 6768 Comm: syz-executor1 Not tainted 4.9.0 #5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
ffff8801c063ecd8 ffffffff82346bdf ffffffff00000001 1ffff100380c7d2e
ffffed00380c7d26 0000000041b58ab3 ffffffff84b37e38 ffffffff823468f1
ffffffff84820740 ffffffff84f289c0 dffffc0000000000 ffff8801c063ee20
Call Trace:
[<ffffffff82346bdf>] __dump_stack lib/dump_stack.c:15 [inline]
[<ffffffff82346bdf>] dump_stack+0x2ee/0x3ef lib/dump_stack.c:51
[<ffffffff81827e34>] panic+0x1fb/0x412 kernel/panic.c:179
[<ffffffff8141f704>] __warn+0x1c4/0x1e0 kernel/panic.c:542
[<ffffffff8141f7e5>] warn_slowpath_fmt+0xc5/0x100 kernel/panic.c:565
[<ffffffff8356cbaf>] skb_warn_bad_offload+0x2af/0x390 net/core/dev.c:2434
[<ffffffff83585cd2>] __skb_gso_segment+0x482/0x780 net/core/dev.c:2706
[<ffffffff83586f19>] skb_gso_segment include/linux/netdevice.h:3985 [inline]
[<ffffffff83586f19>] validate_xmit_skb+0x5c9/0xc20 net/core/dev.c:2969
[<ffffffff835892bb>] __dev_queue_xmit+0xe6b/0x1e70 net/core/dev.c:3383
[<ffffffff8358a2d7>] dev_queue_xmit+0x17/0x20 net/core/dev.c:3424
[<ffffffff83ad161d>] packet_snd net/packet/af_packet.c:2930 [inline]
[<ffffffff83ad161d>] packet_sendmsg+0x32ed/0x4d30 net/packet/af_packet.c:2955
[<ffffffff834f0aaa>] sock_sendmsg_nosec net/socket.c:621 [inline]
[<ffffffff834f0aaa>] sock_sendmsg+0xca/0x110 net/socket.c:631
[<ffffffff834f329a>] ___sys_sendmsg+0x8fa/0x9f0 net/socket.c:1954
[<ffffffff834f5e58>] __sys_sendmsg+0x138/0x300 net/socket.c:1988
[<ffffffff834f604d>] SYSC_sendmsg net/socket.c:1999 [inline]
[<ffffffff834f604d>] SyS_sendmsg+0x2d/0x50 net/socket.c:1995
[<ffffffff84371941>] entry_SYSCALL_64_fastpath+0x1f/0xc2
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Mark Salyzyn <salyzyn@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e44699d2c28067f69698ccb68dd3ddeacfebc434 upstream.
Recently I started seeing warnings about pages with refcount -1. The
problem was traced to packets being reused after their head was merged into
a GRO packet by skb_gro_receive(). While bisecting the issue pointed to
commit c21b48cc1bbf ("net: adjust skb->truesize in ___pskb_trim()") and
I have never seen it on a kernel with it reverted, I believe the real
problem appeared earlier when the option to merge head frag in GRO was
implemented.
Handling NAPI_GRO_FREE_STOLEN_HEAD state was only added to GRO_MERGED_FREE
branch of napi_skb_finish() so that if the driver uses napi_gro_frags()
and head is merged (which in my case happens after the skb_condense()
call added by the commit mentioned above), the skb is reused including the
head that has been merged. As a result, we release the page reference
twice and eventually end up with negative page refcount.
To fix the problem, handle NAPI_GRO_FREE_STOLEN_HEAD in napi_frags_finish()
the same way it's done in napi_skb_finish().
Fixes: d7e8883cfc ("net: make GRO aware of skb->head_frag")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6f64ec74515925cced6df4571638b5a099a49aae upstream.
Similar to the fix provided by Dominik Heidler in commit
9b3dc0a17d73 ("l2tp: cast l2tp traffic counter to unsigned")
we need to take care of 32bit kernels in dev_get_stats().
When using atomic_long_read(), we add a 'long' to u64 and
might misinterpret high order bit, unless we cast to unsigned.
Fixes: caf586e5f2 ("net: add a core netdev->rx_dropped counter")
Fixes: 015f0688f5 ("net: net: add a core netdev->tx_dropped counter")
Fixes: 6e7333d315a76 ("net: add rx_nohandler stat counter")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit db833d40ad3263b2ee3b59a1ba168bb3cfed8137 ]
Network interface groups support added while ago, however
there is no IFLA_GROUP attribute description in policy
and netlink message size calculations until now.
Add IFLA_GROUP attribute to the policy.
Fixes: cbda10fa97 ("net_device: add support for network device groups")
Signed-off-by: Serhey Popovych <serhe.popovych@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f186ce61bb8235d80068c390dc2aad7ca427a4c2 ]
It looks like this:
Message from syslogd@flamingo at Apr 26 00:45:00 ...
kernel:unregister_netdevice: waiting for lo to become free. Usage count = 4
They seem to coincide with net namespace teardown.
The message is emitted by netdev_wait_allrefs().
Forced a kdump in netdev_run_todo, but found that the refcount on the lo
device was already 0 at the time we got to the panic.
Used bcc to check the blocking in netdev_run_todo. The only places
where we're off cpu there are in the rcu_barrier() and msleep() calls.
That behavior is expected. The msleep time coincides with the amount of
time we spend waiting for the refcount to reach zero; the rcu_barrier()
wait times are not excessive.
After looking through the list of callbacks that the netdevice notifiers
invoke in this path, it appears that the dst_dev_event is the most
interesting. The dst_ifdown path places a hold on the loopback_dev as
part of releasing the dev associated with the original dst cache entry.
Most of our notifier callbacks are straight-forward, but this one a)
looks complex, and b) places a hold on the network interface in
question.
I constructed a new bcc script that watches various events in the
liftime of a dst cache entry. Note that dst_ifdown will take a hold on
the loopback device until the invalidated dst entry gets freed.
[ __dst_free] on DST: ffff883ccabb7900 IF tap1008300eth0 invoked at 1282115677036183
__dst_free
rcu_nocb_kthread
kthread
ret_from_fork
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0eed9cf58446b28b233388b7f224cbca268b6986 ]
Some of the structure's fields are not initialized by the
rtnetlink. If driver doesn't set those in ndo_get_vf_config(),
they'd leak memory to user.
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
CC: Michal Schmidt <mschmidt@redhat.com>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit c28294b941232931fbd714099798eb7aa7e865d7 ]
KMSAN reported a use of uninitialized memory in dev_set_alias(),
which was caused by calling strlcpy() (which in turn called strlen())
on the user-supplied non-terminated string.
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 52bd2d62ce6758d811edcbd2256eb9ea7f6a56cb upstream.
skb->sender_cpu and skb->napi_id share a common storage,
and we had various bugs about this.
We had to call skb_sender_cpu_clear() in some places to
not leave a prior skb->napi_id and fool netdev_pick_tx()
As suggested by Alexei, we could split the space so that
these errors can not happen.
0 value being reserved as the common (not initialized) value,
let's reserve [1 .. NR_CPUS] range for valid sender_cpu,
and [NR_CPUS+1 .. ~0U] for valid napi_id.
This will allow proper busy polling support over tunnels.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f6ba8d33cfbb46df569972e64dbb5bb7e929bfd9 upstream.
I should have known that lowering skb->truesize was dangerous :/
In case packets are not leaving the host via a standard Ethernet device,
but looped back to local sockets, bad things can happen, as reported
by Michael Madsen ( https://bugzilla.kernel.org/show_bug.cgi?id=195713 )
So instead of tweaking skb->truesize, lets change skb->destructor
and keep a reference on the owner socket via its sk_refcnt.
Fixes: f2f872f927 ("netem: Introduce skb_orphan_partial() helper")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Michael Madsen <mkm@nabto.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3fb07daff8e99243366a081e5129560734de4ada ]
Andrey Konovalov reported crashes in ipv4_mtu()
I could reproduce the issue with KASAN kernels, between
10.246.7.151 and 10.246.7.152 :
1) 20 concurrent netperf -t TCP_RR -H 10.246.7.152 -l 1000 &
2) At the same time run following loop :
while :
do
ip ro add 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500
ip ro del 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500
done
Cong Wang attempted to add back rt->fi in commit
82486aa6f1b9 ("ipv4: restore rt->fi for reference counting")
but this proved to add some issues that were complex to solve.
Instead, I suggested to add a refcount to the metrics themselves,
being a standalone object (in particular, no reference to other objects)
I tried to make this patch as small as possible to ease its backport,
instead of being super clean. Note that we believe that only ipv4 dst
need to take care of the metric refcount. But if this is wrong,
this patch adds the basic infrastructure to extend this to other
families.
Many thanks to Julian Anastasov for reviewing this patch, and Cong Wang
for his efforts on this problem.
Fixes: 2860583fe8 ("ipv4: Kill rt->fi")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f6c5775ff0bfa62b072face6bf1d40f659f194b2 ]
In general, rtnetlink dumps do not anticipate failure to dump a single
object (e.g., link or route) on a single pass. As both route and link
objects have grown via more attributes, that is no longer a given.
netlink dumps can handle a failure if the dump function returns an
error; specifically, netlink_dump adds the return code to the response
if it is <= 0 so userspace is notified of the failure. The missing
piece is the rtnetlink dump functions returning the error.
Fix route and link dump functions to return the errors if no object is
added to an skb (detected by skb->len != 0). IPv6 route dumps
(rt6_dump_route) already return the error; this patch updates IPv4 and
link dumps. Other dump functions may need to be ajusted as well.
Reported-by: Jan Moskyto Matejka <mq@ucw.cz>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 77ef033b687c3e030017c94a29bf6ea3aaaef678 ]
IFLA_PHYS_PORT_NAME is a string attribute, so terminate it with \0.
Otherwise libnl3 fails to validate netlink messages with this attribute.
"ip -detail a" assumes too that the attribute is NUL-terminated when
printing it. It often was, due to padding.
I noticed this as libvirtd failing to start on a system with sfc driver
after upgrading it to Linux 4.11, i.e. when sfc added support for
phys_port_name.
Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 48481c8fa16410ffa45939b13b6c53c2ca609e5f ]
Dmitry posted a nice reproducer of a bug triggering in neigh_probe()
when dereferencing a NULL neigh->ops->solicit method.
This can happen for arp_direct_ops/ndisc_direct_ops and similar,
which can be used for NUD_NOARP neighbours (created when dev->header_ops
is NULL). Admin can then force changing nud_state to some other state
that would fire neigh timer.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a97e50cc4cb67e1e7bff56f6b41cda62ca832336 ]
In sk_clone_lock(), we create a new socket and inherit most of the
parent's members via sock_copy() which memcpy()'s various sections.
Now, in case the parent socket had a BPF socket filter attached,
then newsk->sk_filter points to the same instance as the original
sk->sk_filter.
sk_filter_charge() is then called on the newsk->sk_filter to take a
reference and should that fail due to hitting max optmem, we bail
out and release the newsk instance.
The issue is that commit 278571baca ("net: filter: simplify socket
charging") wrongly combined the dismantle path with the failure path
of xfrm_sk_clone_policy(). This means, even when charging failed, we
call sk_free_unlock_clone() on the newsk, which then still points to
the same sk_filter as the original sk.
Thus, sk_free_unlock_clone() calls into __sk_destruct() eventually
where it tests for present sk_filter and calls sk_filter_uncharge()
on it, which potentially lets sk_omem_alloc wrap around and releases
the eBPF prog and sk_filter structure from the (still intact) parent.
Fix it by making sure that when sk_filter_charge() failed, we reset
newsk->sk_filter back to NULL before passing to sk_free_unlock_clone(),
so that we don't mess with the parents sk_filter.
Only if xfrm_sk_clone_policy() fails, we did reach the point where
either the parent's filter was NULL and as a result newsk's as well
or where we previously had a successful sk_filter_charge(), thus for
that case, we do need sk_filter_uncharge() to release the prior taken
reference on sk_filter.
Fixes: 278571baca ("net: filter: simplify socket charging")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 22a0e18eac7a9e986fec76c60fa4a2926d1291e2 ]
I mistakenly added the code to release sk->sk_frag in
sk_common_release() instead of sk_destruct()
TCP sockets using sk->sk_allocation == GFP_ATOMIC do no call
sk_common_release() at close time, thus leaking one (order-3) page.
iSCSI is using such sockets.
Fixes: 5640f76858 ("net: use a per task frag allocator")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9ac25fc063751379cb77434fef9f3b088cd3e2f7 ]
TX skbs do not necessarily hold a reference on skb->sk->sk_refcnt
By the time TX completion happens, sk_refcnt might be already 0.
sock_hold()/sock_put() would then corrupt critical state, like
sk_wmem_alloc and lead to leaks or use after free.
Fixes: 62bccb8cdb ("net-timestamp: Make the clone operation stand-alone from phy timestamping")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit dd4f10722aeb10f4f582948839f066bebe44e5fb ]
TX skbs do not necessarily hold a reference on skb->sk->sk_refcnt
By the time TX completion happens, sk_refcnt might be already 0.
sock_hold()/sock_put() would then corrupt critical state, like
sk_wmem_alloc.
Fixes: bf7fa551e0 ("mac80211: Resolve sk_refcnt/sk_wmem_alloc issue in wifi ack path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 13baa00ad01bb3a9f893e3a08cbc2d072fc0c15d ]
It is now very clear that silly TCP listeners might play with
enabling/disabling timestamping while new children are added
to their accept queue.
Meaning net_enable_timestamp() can be called from BH context
while current state of the static key is not enabled.
Lets play safe and allow all contexts.
The work queue is scheduled only under the problematic cases,
which are the static key enable/disable transition, to not slow down
critical paths.
This extends and improves what we did in commit 5fa8bbda38c6 ("net: use
a work queue to defer net_disable_timestamp() work")
Fixes: b90e5794c5 ("net: dont call jump_label_dec from irq context")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7be2c82cfd5d28d7adb66821a992604eb6dd112e ]
Ashizuka reported a highmem oddity and sent a patch for freescale
fec driver.
But the problem root cause is that core networking stack
must ensure no skb with highmem fragment is ever sent through
a device that does not assert NETIF_F_HIGHDMA in its features.
We need to call illegal_highdma() from harmonize_features()
regardless of CSUM checks.
Fixes: ec5f061564 ("net: Kill link between CSUM and SG features.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Pravin Shelar <pshelar@ovn.org>
Reported-by: "Ashizuka, Yuusuke" <ashiduka@jp.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7cfd5fd5a9813f1430290d20c0fead9b4582a307 ]
On 32bit arches, (skb->end - skb->data) is not 'unsigned int',
so we shall use min_t() instead of min() to avoid a compiler error.
Fixes: 1272ce87fa01 ("gro: Enter slow-path if there is no tailroom")
Reported-by: kernel test robot <fengguang.wu@intel.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1272ce87fa017ca4cf32920764d879656b7a005a ]
The GRO path has a fast-path where we avoid calling pskb_may_pull
and pskb_expand by directly accessing frag0. However, this should
only be done if we have enough tailroom in the skb as otherwise
we'll have to expand it later anyway.
This patch adds the check by capping frag0_len with the skb tailroom.
Fixes: cb18978cbf ("gro: Open-code final pskb_may_pull")
Reported-by: Slava Shwartsman <slavash@mellanox.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3b48ab2248e61408910e792fe84d6ec466084c1a ]
Final nlmsg_len field update must reflect inserted net_dm_drop_point
data.
This patch depends on previous patch:
"drop_monitor: add missing call to genlmsg_end"
Signed-off-by: Reiter Wolfgang <wr0112358@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4200462d88f47f3759bdf4705f87e207b0f5b2e4 ]
Update nlmsg_len field with genlmsg_end to enable userspace processing
using nlmsg_next helper. Also adds error handling.
Signed-off-by: Reiter Wolfgang <wr0112358@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b98b0bc8c431e3ceb4b26b0dfc8db509518fb290 ]
CAP_NET_ADMIN users should not be allowed to set negative
sk_sndbuf or sk_rcvbuf values, as it can lead to various memory
corruptions, crashes, OOM...
Note that before commit 8298193012 ("net: cleanups in
sock_setsockopt()"), the bug was even more serious, since SO_SNDBUF
and SO_RCVBUF were vulnerable.
This needs to be backported to all known linux kernels.
Again, many thanks to syzkaller team for discovering this gem.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit cfc44a4d147ea605d66ccb917cc24467d15ff867 ]
Andrei reports we still allocate netns ID from idr after we destroy
it in cleanup_net().
cleanup_net():
...
idr_destroy(&net->netns_ids);
...
list_for_each_entry_reverse(ops, &pernet_list, list)
ops_exit_list(ops, &net_exit_list);
-> rollback_registered_many()
-> rtmsg_ifinfo_build_skb()
-> rtnl_fill_ifinfo()
-> peernet2id_alloc()
After that point we should not even access net->netns_ids, we
should check the death of the current netns as early as we can in
peernet2id_alloc().
For net-next we can consider to avoid sending rtmsg totally,
it is a good optimization for netns teardown path.
Fixes: 0c7aecd4bd ("netns: add rtnl cmd to add and get peer netns ids")
Reported-by: Andrei Vagin <avagin@gmail.com>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c9b8af1330198ae241cd545e1f040019010d44d9 upstream.
Andre Noll reported panics after my recent fix (commit 34fad54c2537
"net: __skb_flow_dissect() must cap its return value")
After some more headaches, Alexander root caused the problem to
init_default_flow_dissectors() being called too late, in case
a network driver like IGB is not a module and receives DHCP message
very early.
Fix is to call init_default_flow_dissectors() much earlier,
as it is a core infrastructure and does not depend on another
kernel service.
Fixes: 06635a35d1 ("flow_dissect: use programable dissector in skb_flow_dissect and friends")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andre Noll <maan@tuebingen.mpg.de>
Diagnosed-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ac6e780070e30e4c35bd395acfe9191e6268bdd3 ]
With syzkaller help, Marco Grassi found a bug in TCP stack,
crashing in tcp_collapse()
Root cause is that sk_filter() can truncate the incoming skb,
but TCP stack was not really expecting this to happen.
It probably was expecting a simple DROP or ACCEPT behavior.
We first need to make sure no part of TCP header could be removed.
Then we need to adjust TCP_SKB_CB(skb)->end_seq
Many thanks to syzkaller team and Marco for giving us a reproducer.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Marco Grassi <marco.gra@gmail.com>
Reported-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 34fad54c2537f7c99d07375e50cb30aa3c23bd83 ]
After Tom patch, thoff field could point past the end of the buffer,
this could fool some callers.
If an skb was provided, skb->len should be the upper limit.
If not, hlen is supposed to be the upper limit.
Fixes: a6e544b0a8 ("flow_dissector: Jump to exit code in __skb_flow_dissect")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Yibin Yang <yibyang@cisco.com
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4f2e4ad56a65f3b7d64c258e373cb71e8d2499f4 ]
Sending zero checksum is ok for TCP, but not for UDP.
UDPv6 receiver should by default drop a frame with a 0 checksum,
and UDPv4 would not verify the checksum and might accept a corrupted
packet.
Simply replace such checksum by 0xffff, regardless of transport.
This error was caught on SIT tunnels, but seems generic.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Acked-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
