[ Upstream commit 76be5fae32 ]
We observed an issue from the latest selftest: sockmap_redir where
sk_psock(psock->sk) != psock in the backlog. The root cause is the special
behavior in sockmap_redir - it frequently performs map_update() and
map_delete() on the same socket. During map_update(), we create a new
psock and during map_delete(), we eventually free the psock via rcu_work
in sk_psock_drop(). However, pending workqueues might still exist and not
be processed yet. If users immediately perform another map_update(), a new
psock will be allocated for the same sk, resulting in two psocks pointing
to the same sk.
When the pending workqueue is later triggered, it uses the old psock to
access sk for I/O operations, which is incorrect.
Timing Diagram:
cpu0 cpu1
map_update(sk):
sk->psock = psock1
psock1->sk = sk
map_delete(sk):
rcu_work_free(psock1)
map_update(sk):
sk->psock = psock2
psock2->sk = sk
workqueue:
wakeup with psock1, but the sk of psock1
doesn't belong to psock1
rcu_handler:
clean psock1
free(psock1)
Previously, we used reference counting to address the concurrency issue
between backlog and sock_map_close(). This logic remains necessary as it
prevents the sk from being freed while processing the backlog. But this
patch prevents pending backlogs from using a psock after it has been
stopped.
Note: We cannot call cancel_delayed_work_sync() in map_delete() since this
might be invoked in BPF context by BPF helper, and the function may sleep.
Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20250609025908.79331-1-jiayuan.chen@linux.dev
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ead7f9b8de upstream.
In Cilium, we use bpf_csum_diff + bpf_l4_csum_replace to, among other
things, update the L4 checksum after reverse SNATing IPv6 packets. That
use case is however not currently supported and leads to invalid
skb->csum values in some cases. This patch adds support for IPv6 address
changes in bpf_l4_csum_update via a new flag.
When calling bpf_l4_csum_replace in Cilium, it ends up calling
inet_proto_csum_replace_by_diff:
1: void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb,
2: __wsum diff, bool pseudohdr)
3: {
4: if (skb->ip_summed != CHECKSUM_PARTIAL) {
5: csum_replace_by_diff(sum, diff);
6: if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
7: skb->csum = ~csum_sub(diff, skb->csum);
8: } else if (pseudohdr) {
9: *sum = ~csum_fold(csum_add(diff, csum_unfold(*sum)));
10: }
11: }
The bug happens when we're in the CHECKSUM_COMPLETE state. We've just
updated one of the IPv6 addresses. The helper now updates the L4 header
checksum on line 5. Next, it updates skb->csum on line 7. It shouldn't.
For an IPv6 packet, the updates of the IPv6 address and of the L4
checksum will cancel each other. The checksums are set such that
computing a checksum over the packet including its checksum will result
in a sum of 0. So the same is true here when we update the L4 checksum
on line 5. We'll update it as to cancel the previous IPv6 address
update. Hence skb->csum should remain untouched in this case.
The same bug doesn't affect IPv4 packets because, in that case, three
fields are updated: the IPv4 address, the IP checksum, and the L4
checksum. The change to the IPv4 address and one of the checksums still
cancel each other in skb->csum, but we're left with one checksum update
and should therefore update skb->csum accordingly. That's exactly what
inet_proto_csum_replace_by_diff does.
This special case for IPv6 L4 checksums is also described atop
inet_proto_csum_replace16, the function we should be using in this case.
This patch introduces a new bpf_l4_csum_replace flag, BPF_F_IPV6,
to indicate that we're updating the L4 checksum of an IPv6 packet. When
the flag is set, inet_proto_csum_replace_by_diff will skip the
skb->csum update.
Fixes: 7d672345ed ("bpf: add generic bpf_csum_diff helper")
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/96a6bc3a443e6f0b21ff7b7834000e17fb549e05.1748509484.git.paul.chaignon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6043b794c7 upstream.
During ILA address translations, the L4 checksums can be handled in
different ways. One of them, adj-transport, consist in parsing the
transport layer and updating any found checksum. This logic relies on
inet_proto_csum_replace_by_diff and produces an incorrect skb->csum when
in state CHECKSUM_COMPLETE.
This bug can be reproduced with a simple ILA to SIR mapping, assuming
packets are received with CHECKSUM_COMPLETE:
$ ip a show dev eth0
14: eth0@if15: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 62:ae:35:9e:0f:8d brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet6 3333:0:0:1::c078/64 scope global
valid_lft forever preferred_lft forever
inet6 fd00:10:244:1::c078/128 scope global nodad
valid_lft forever preferred_lft forever
inet6 fe80::60ae:35ff:fe9e:f8d/64 scope link proto kernel_ll
valid_lft forever preferred_lft forever
$ ip ila add loc_match fd00:10:244:1 loc 3333:0:0:1 \
csum-mode adj-transport ident-type luid dev eth0
Then I hit [fd00:10:244:1::c078]:8000 with a server listening only on
[3333:0:0:1::c078]:8000. With the bug, the SYN packet is dropped with
SKB_DROP_REASON_TCP_CSUM after inet_proto_csum_replace_by_diff changed
skb->csum. The translation and drop are visible on pwru [1] traces:
IFACE TUPLE FUNC
eth0:9 [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp) ipv6_rcv
eth0:9 [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp) ip6_rcv_core
eth0:9 [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp) nf_hook_slow
eth0:9 [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp) inet_proto_csum_replace_by_diff
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) tcp_v6_early_demux
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) ip6_route_input
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) ip6_input
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) ip6_input_finish
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) ip6_protocol_deliver_rcu
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) raw6_local_deliver
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) ipv6_raw_deliver
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) tcp_v6_rcv
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) __skb_checksum_complete
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) kfree_skb_reason(SKB_DROP_REASON_TCP_CSUM)
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) skb_release_head_state
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) skb_release_data
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) skb_free_head
eth0:9 [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp) kfree_skbmem
This is happening because inet_proto_csum_replace_by_diff is updating
skb->csum when it shouldn't. The L4 checksum is updated such that it
"cancels" the IPv6 address change in terms of checksum computation, so
the impact on skb->csum is null.
Note this would be different for an IPv4 packet since three fields
would be updated: the IPv4 address, the IP checksum, and the L4
checksum. Two would cancel each other and skb->csum would still need
to be updated to take the L4 checksum change into account.
This patch fixes it by passing an ipv6 flag to
inet_proto_csum_replace_by_diff, to skip the skb->csum update if we're
in the IPv6 case. Note the behavior of the only other user of
inet_proto_csum_replace_by_diff, the BPF subsystem, is left as is in
this patch and fixed in the subsequent patch.
With the fix, using the reproduction from above, I can confirm
skb->csum is not touched by inet_proto_csum_replace_by_diff and the TCP
SYN proceeds to the application after the ILA translation.
Link: https://github.com/cilium/pwru [1]
Fixes: 65d7ab8de5 ("net: Identifier Locator Addressing module")
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/b5539869e3550d46068504feb02d37653d939c0b.1748509484.git.paul.chaignon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8259eb0e06 ]
The sk->sk_socket is not locked or referenced in backlog thread, and
during the call to skb_send_sock(), there is a race condition with
the release of sk_socket. All types of sockets(tcp/udp/unix/vsock)
will be affected.
Race conditions:
'''
CPU0 CPU1
backlog::skb_send_sock
sendmsg_unlocked
sock_sendmsg
sock_sendmsg_nosec
close(fd):
...
ops->release() -> sock_map_close()
sk_socket->ops = NULL
free(socket)
sock->ops->sendmsg
^
panic here
'''
The ref of psock become 0 after sock_map_close() executed.
'''
void sock_map_close()
{
...
if (likely(psock)) {
...
// !! here we remove psock and the ref of psock become 0
sock_map_remove_links(sk, psock)
psock = sk_psock_get(sk);
if (unlikely(!psock))
goto no_psock; <=== Control jumps here via goto
...
cancel_delayed_work_sync(&psock->work); <=== not executed
sk_psock_put(sk, psock);
...
}
'''
Based on the fact that we already wait for the workqueue to finish in
sock_map_close() if psock is held, we simply increase the psock
reference count to avoid race conditions.
With this patch, if the backlog thread is running, sock_map_close() will
wait for the backlog thread to complete and cancel all pending work.
If no backlog running, any pending work that hasn't started by then will
fail when invoked by sk_psock_get(), as the psock reference count have
been zeroed, and sk_psock_drop() will cancel all jobs via
cancel_delayed_work_sync().
In summary, we require synchronization to coordinate the backlog thread
and close() thread.
The panic I catched:
'''
Workqueue: events sk_psock_backlog
RIP: 0010:sock_sendmsg+0x21d/0x440
RAX: 0000000000000000 RBX: ffffc9000521fad8 RCX: 0000000000000001
...
Call Trace:
<TASK>
? die_addr+0x40/0xa0
? exc_general_protection+0x14c/0x230
? asm_exc_general_protection+0x26/0x30
? sock_sendmsg+0x21d/0x440
? sock_sendmsg+0x3e0/0x440
? __pfx_sock_sendmsg+0x10/0x10
__skb_send_sock+0x543/0xb70
sk_psock_backlog+0x247/0xb80
...
'''
Fixes: 4b4647add7 ("sock_map: avoid race between sock_map_close and sk_psock_put")
Reported-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20250516141713.291150-1-jiayuan.chen@linux.dev
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3b4f14b794 ]
In the !ingress path under sk_psock_handle_skb(), when sending data to the
remote under snd_buf limitations, partial skb data might be transmitted.
Although we preserved the partial transmission state (offset/length), the
state wasn't properly consumed during retries. This caused the retry path
to resend the entire skb data instead of continuing from the previous
offset, resulting in data overlap at the receiver side.
Fixes: 405df89dd5 ("bpf, sockmap: Improved check for empty queue")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://lore.kernel.org/r/20250407142234.47591-3-jiayuan.chen@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7172dc93d6 upstream.
Commit 1af2dface5 ("af_unix: Don't access successor in unix_del_edges()
during GC.") fixed use-after-free by avoid accessing edge->successor while
GC is in progress.
However, there could be a small race window where another process could
call unix_del_edges() while gc_in_progress is true and __skb_queue_purge()
is on the way.
So, we need another marker for struct scm_fp_list which indicates if the
skb is garbage-collected.
This patch adds dead flag in struct scm_fp_list and set it true before
calling __skb_queue_purge().
Fixes: 1af2dface5 ("af_unix: Don't access successor in unix_del_edges() during GC.")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240508171150.50601-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 29b64e3540 upstream.
As with the previous patch, we preallocate to skb's scm_fp_list an
array of struct unix_edge in the number of inflight AF_UNIX fds.
There we just preallocate memory and do not use immediately because
sendmsg() could fail after this point. The actual use will be in
the next patch.
When we queue skb with inflight edges, we will set the inflight
socket's unix_sock as unix_edge->predecessor and the receiver's
unix_sock as successor, and then we will link the edge to the
inflight socket's unix_vertex.edges.
Note that we set NULL to cloned scm_fp_list.edges in scm_fp_dup()
so that MSG_PEEK does not change the shape of the directed graph.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240325202425.60930-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1fbfdfaa59 upstream.
We will replace the garbage collection algorithm for AF_UNIX, where
we will consider each inflight AF_UNIX socket as a vertex and its file
descriptor as an edge in a directed graph.
This patch introduces a new struct unix_vertex representing a vertex
in the graph and adds its pointer to struct unix_sock.
When we send a fd using the SCM_RIGHTS message, we allocate struct
scm_fp_list to struct scm_cookie in scm_fp_copy(). Then, we bump
each refcount of the inflight fds' struct file and save them in
scm_fp_list.fp.
After that, unix_attach_fds() inexplicably clones scm_fp_list of
scm_cookie and sets it to skb. (We will remove this part after
replacing GC.)
Here, we add a new function call in unix_attach_fds() to preallocate
struct unix_vertex per inflight AF_UNIX fd and link each vertex to
skb's scm_fp_list.vertices.
When sendmsg() succeeds later, if the socket of the inflight fd is
still not inflight yet, we will set the preallocated vertex to struct
unix_sock.vertex and link it to a global list unix_unvisited_vertices
under spin_lock(&unix_gc_lock).
If the socket is already inflight, we free the preallocated vertex.
This is to avoid taking the lock unnecessarily when sendmsg() could
fail later.
In the following patch, we will similarly allocate another struct
per edge, which will finally be linked to the inflight socket's
unix_vertex.edges.
And then, we will count the number of edges as unix_vertex.out_degree.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240325202425.60930-2-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d9f21b3613 upstream.
If more than 16000 inflight AF_UNIX sockets exist and the garbage
collector is not running, unix_(dgram|stream)_sendmsg() call unix_gc().
Also, they wait for unix_gc() to complete.
In unix_gc(), all inflight AF_UNIX sockets are traversed at least once,
and more if they are the GC candidate. Thus, sendmsg() significantly
slows down with too many inflight AF_UNIX sockets.
However, if a process sends data with no AF_UNIX FD, the sendmsg() call
does not need to wait for GC. After this change, only the process that
meets the condition below will be blocked under such a situation.
1) cmsg contains AF_UNIX socket
2) more than 32 AF_UNIX sent by the same user are still inflight
Note that even a sendmsg() call that does not meet the condition but has
AF_UNIX FD will be blocked later in unix_scm_to_skb() by the spinlock,
but we allow that as a bonus for sane users.
The results below are the time spent in unix_dgram_sendmsg() sending 1
byte of data with no FD 4096 times on a host where 32K inflight AF_UNIX
sockets exist.
Without series: the sane sendmsg() needs to wait gc unreasonably.
$ sudo /usr/share/bcc/tools/funclatency -p 11165 unix_dgram_sendmsg
Tracing 1 functions for "unix_dgram_sendmsg"... Hit Ctrl-C to end.
^C
nsecs : count distribution
[...]
524288 -> 1048575 : 0 | |
1048576 -> 2097151 : 3881 |****************************************|
2097152 -> 4194303 : 214 |** |
4194304 -> 8388607 : 1 | |
avg = 1825567 nsecs, total: 7477526027 nsecs, count: 4096
With series: the sane sendmsg() can finish much faster.
$ sudo /usr/share/bcc/tools/funclatency -p 8702 unix_dgram_sendmsg
Tracing 1 functions for "unix_dgram_sendmsg"... Hit Ctrl-C to end.
^C
nsecs : count distribution
[...]
128 -> 255 : 0 | |
256 -> 511 : 4092 |****************************************|
512 -> 1023 : 2 | |
1024 -> 2047 : 0 | |
2048 -> 4095 : 0 | |
4096 -> 8191 : 1 | |
8192 -> 16383 : 1 | |
avg = 410 nsecs, total: 1680510 nsecs, count: 4096
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240123170856.41348-6-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2b15a0693f ]
Fix mpls maximum labels list parsing up to MAX_MPLS_LABELS entries (instead
of up to MAX_MPLS_LABELS - 1).
Addresses the following:
$ echo "mpls 00000f00,00000f01,00000f02,00000f03,00000f04,00000f05,00000f06,00000f07,00000f08,00000f09,00000f0a,00000f0b,00000f0c,00000f0d,00000f0e,00000f0f" > /proc/net/pktgen/lo\@0
-bash: echo: write error: Argument list too long
Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c432722994 ]
When bpf_redirect_peer is used to redirect packets to a device in
another network namespace, the skb isn't scrubbed. That can lead skb
information from one namespace to be "misused" in another namespace.
As one example, this is causing Cilium to drop traffic when using
bpf_redirect_peer to redirect packets that just went through IPsec
decryption to a container namespace. The following pwru trace shows (1)
the packet path from the host's XFRM layer to the container's XFRM
layer where it's dropped and (2) the number of active skb extensions at
each function.
NETNS MARK IFACE TUPLE FUNC
4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 xfrm_rcv_cb
.active_extensions = (__u8)2,
4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 xfrm4_rcv_cb
.active_extensions = (__u8)2,
4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 gro_cells_receive
.active_extensions = (__u8)2,
[...]
4026533547 0 eth0 10.244.3.124:35473->10.244.2.158:53 skb_do_redirect
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 ip_rcv
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 ip_rcv_core
.active_extensions = (__u8)2,
[...]
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 udp_queue_rcv_one_skb
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 __xfrm_policy_check
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 __xfrm_decode_session
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 security_xfrm_decode_session
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 kfree_skb_reason(SKB_DROP_REASON_XFRM_POLICY)
.active_extensions = (__u8)2,
In this case, there are no XFRM policies in the container's network
namespace so the drop is unexpected. When we decrypt the IPsec packet,
the XFRM state used for decryption is set in the skb extensions. This
information is preserved across the netns switch. When we reach the
XFRM policy check in the container's netns, __xfrm_policy_check drops
the packet with LINUX_MIB_XFRMINNOPOLS because a (container-side) XFRM
policy can't be found that matches the (host-side) XFRM state used for
decryption.
This patch fixes this by scrubbing the packet when using
bpf_redirect_peer, as is done on typical netns switches via veth
devices except skb->mark and skb->tstamp are not zeroed.
Fixes: 9aa1206e8f ("bpf: Add redirect_peer helper")
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/1728ead5e0fe45e7a6542c36bd4e3ca07a73b7d6.1746460653.git.paul.chaignon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d4bac0288a ]
Classic BPF socket filters with SKB_NET_OFF and SKB_LL_OFF fail to
read when these offsets extend into frags.
This has been observed with iwlwifi and reproduced with tun with
IFF_NAPI_FRAGS. The below straightforward socket filter on UDP port,
applied to a RAW socket, will silently miss matching packets.
const int offset_proto = offsetof(struct ip6_hdr, ip6_nxt);
const int offset_dport = sizeof(struct ip6_hdr) + offsetof(struct udphdr, dest);
struct sock_filter filter_code[] = {
BPF_STMT(BPF_LD + BPF_B + BPF_ABS, SKF_AD_OFF + SKF_AD_PKTTYPE),
BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, PACKET_HOST, 0, 4),
BPF_STMT(BPF_LD + BPF_B + BPF_ABS, SKF_NET_OFF + offset_proto),
BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, IPPROTO_UDP, 0, 2),
BPF_STMT(BPF_LD + BPF_H + BPF_ABS, SKF_NET_OFF + offset_dport),
This is unexpected behavior. Socket filter programs should be
consistent regardless of environment. Silent misses are
particularly concerning as hard to detect.
Use skb_copy_bits for offsets outside linear, same as done for
non-SKF_(LL|NET) offsets.
Offset is always positive after subtracting the reference threshold
SKB_(LL|NET)_OFF, so is always >= skb_(mac|network)_offset. The sum of
the two is an offset against skb->data, and may be negative, but it
cannot point before skb->head, as skb_(mac|network)_offset would too.
This appears to go back to when frag support was introduced to
sk_run_filter in linux-2.4.4, before the introduction of git.
The amount of code change and 8/16/32 bit duplication are unfortunate.
But any attempt I made to be smarter saved very few LoC while
complicating the code.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Link: https://lore.kernel.org/netdev/20250122200402.3461154-1-maze@google.com/
Link: https://elixir.bootlin.com/linux/2.4.4/source/net/core/filter.c#L244
Reported-by: Matt Moeller <moeller.matt@gmail.com>
Co-developed-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://lore.kernel.org/r/20250408132833.195491-2-willemdebruijn.kernel@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 43130d02ba ]
We noticed the kworker in page_pool_release_retry() was waken
up repeatedly and infinitely in production because of the
buggy driver causing the inflight less than 0 and warning
us in page_pool_inflight()[1].
Since the inflight value goes negative, it means we should
not expect the whole page_pool to get back to work normally.
This patch mitigates the adverse effect by not rescheduling
the kworker when detecting the inflight negative in
page_pool_release_retry().
[1]
[Mon Feb 10 20:36:11 2025] ------------[ cut here ]------------
[Mon Feb 10 20:36:11 2025] Negative(-51446) inflight packet-pages
...
[Mon Feb 10 20:36:11 2025] Call Trace:
[Mon Feb 10 20:36:11 2025] page_pool_release_retry+0x23/0x70
[Mon Feb 10 20:36:11 2025] process_one_work+0x1b1/0x370
[Mon Feb 10 20:36:11 2025] worker_thread+0x37/0x3a0
[Mon Feb 10 20:36:11 2025] kthread+0x11a/0x140
[Mon Feb 10 20:36:11 2025] ? process_one_work+0x370/0x370
[Mon Feb 10 20:36:11 2025] ? __kthread_cancel_work+0x40/0x40
[Mon Feb 10 20:36:11 2025] ret_from_fork+0x35/0x40
[Mon Feb 10 20:36:11 2025] ---[ end trace ebffe800f33e7e34 ]---
Note: before this patch, the above calltrace would flood the
dmesg due to repeated reschedule of release_dw kworker.
Signed-off-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20250214064250.85987-1-kerneljasonxing@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 90a7138619 ]
Previous commit 8b5c171bb3 ("neigh: new unresolved queue limits")
introduces new netlink attribute NDTPA_QUEUE_LENBYTES to represent
approximative value for deprecated QUEUE_LEN. However, it forgot to add
the associated nla_policy in nl_ntbl_parm_policy array. Fix it with one
simple NLA_U32 type policy.
Fixes: 8b5c171bb3 ("neigh: new unresolved queue limits")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Link: https://patch.msgid.link/20250315165113.37600-1-linma@zju.edu.cn
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 986ffb3a57 ]
This patch acts as a parachute, catch all solution, by detecting
recursion loops in lwtunnel users and taking care of them (e.g., a loop
between routes, a loop within the same route, etc). In general, such
loops are the consequence of pathological configurations. Each lwtunnel
user is still free to catch such loops early and do whatever they want
with them. It will be the case in a separate patch for, e.g., seg6 and
seg6_local, in order to provide drop reasons and update statistics.
Another example of a lwtunnel user taking care of loops is ioam6, which
has valid use cases that include loops (e.g., inline mode), and which is
addressed by the next patch in this series. Overall, this patch acts as
a last resort to catch loops and drop packets, since we don't want to
leak something unintentionally because of a pathological configuration
in lwtunnels.
The solution in this patch reuses dev_xmit_recursion(),
dev_xmit_recursion_inc(), and dev_xmit_recursion_dec(), which seems fine
considering the context.
Closes: https://lore.kernel.org/netdev/2bc9e2079e864a9290561894d2a602d6@akamai.com/
Closes: https://lore.kernel.org/netdev/Z7NKYMY7fJT5cYWu@shredder/
Fixes: ffce41962e ("lwtunnel: support dst output redirect function")
Fixes: 2536862311 ("lwt: Add support to redirect dst.input")
Fixes: 14972cbd34 ("net: lwtunnel: Handle fragmentation")
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Link: https://patch.msgid.link/20250314120048.12569-2-justin.iurman@uliege.be
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 505ead7ab7 ]
The function __netpoll_send_skb() is being invoked without holding the
RCU read lock. This oversight triggers a warning message when
CONFIG_PROVE_RCU_LIST is enabled:
net/core/netpoll.c:330 suspicious rcu_dereference_check() usage!
netpoll_send_skb
netpoll_send_udp
write_ext_msg
console_flush_all
console_unlock
vprintk_emit
To prevent npinfo from disappearing unexpectedly, ensure that
__netpoll_send_skb() is protected with the RCU read lock.
Fixes: 2899656b49 ("netpoll: take rcu_read_lock_bh() in netpoll_send_skb_on_dev()")
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250306-netpoll_rcu_v2-v2-1-bc4f5c51742a@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 49806fe6e6 ]
In certain cases, napi_get_frags() returns an skb that points to an old
received fragment, This skb may have its skb->ip_summed, csum, and other
fields set from previous fragment handling.
Some network drivers set skb->ip_summed to either CHECKSUM_COMPLETE or
CHECKSUM_UNNECESSARY when getting skb from napi_get_frags(), while
others only set skb->ip_summed when RX checksum offload is enabled on
the device, and do not set any value for skb->ip_summed when hardware
checksum offload is disabled, assuming that the skb->ip_summed
initiated to zero by napi_reuse_skb, ionic driver for example will
ignore/unset any value for the ip_summed filed if HW checksum offload is
disabled, and if we have a situation where the user disables the
checksum offload during a traffic that could lead to the following
errors shown in the kernel logs:
<IRQ>
dump_stack_lvl+0x34/0x48
__skb_gro_checksum_complete+0x7e/0x90
tcp6_gro_receive+0xc6/0x190
ipv6_gro_receive+0x1ec/0x430
dev_gro_receive+0x188/0x360
? ionic_rx_clean+0x25a/0x460 [ionic]
napi_gro_frags+0x13c/0x300
? __pfx_ionic_rx_service+0x10/0x10 [ionic]
ionic_rx_service+0x67/0x80 [ionic]
ionic_cq_service+0x58/0x90 [ionic]
ionic_txrx_napi+0x64/0x1b0 [ionic]
__napi_poll+0x27/0x170
net_rx_action+0x29c/0x370
handle_softirqs+0xce/0x270
__irq_exit_rcu+0xa3/0xc0
common_interrupt+0x80/0xa0
</IRQ>
This inconsistency sometimes leads to checksum validation issues in the
upper layers of the network stack.
To resolve this, this patch clears the skb->ip_summed value for each
reused skb in by napi_reuse_skb(), ensuring that the caller is responsible
for setting the correct checksum status. This eliminates potential
checksum validation issues caused by improper handling of
skb->ip_summed.
Fixes: 76620aafd6 ("gro: New frags interface to avoid copying shinfo")
Signed-off-by: Mohammad Heib <mheib@redhat.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250225112852.2507709-1-mheib@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit de2c211868 ]
We found an issue when using bpf_redirect with ipvs NAT mode after
commit ff70202b2d ("dev_forward_skb: do not scrub skb mark within
the same name space"). Particularly, we use bpf_redirect to return
the skb directly back to the netif it comes from, i.e., xnet is
false in skb_scrub_packet(), and then ipvs_property is preserved
and SNAT is skipped in the rx path.
ipvs_property has been already cleared when netns is changed in
commit 2b5ec1a5f9 ("netfilter/ipvs: clear ipvs_property flag when
SKB net namespace changed"). This patch just clears it in spite of
netns.
Fixes: 2b5ec1a5f9 ("netfilter/ipvs: clear ipvs_property flag when SKB net namespace changed")
Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Link: https://patch.msgid.link/20250222033518.126087-1-lulie@linux.alibaba.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c180188ec0 ]
Commit 7acf8a1e8a ("Replace 2 jiffies with sysctl netdev_budget_usecs
to enable softirq tuning") added a possibility to set
net_hotdata.netdev_budget_usecs, but added no lower bound checking.
Commit a4837980fd ("net: revert default NAPI poll timeout to 2 jiffies")
made the *initial* value HZ-dependent, so the initial value is at least
2 jiffies even for lower HZ values (2 ms for 1000 Hz, 8ms for 250 Hz, 20
ms for 100 Hz).
But a user still can set improper values by a sysctl. Set .extra1
(the lower bound) for net_hotdata.netdev_budget_usecs to the same value
as in the latter commit. That is to 2 jiffies.
Fixes: a4837980fd ("net: revert default NAPI poll timeout to 2 jiffies")
Fixes: 7acf8a1e8a ("Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning")
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Dmitry Yakunin <zeil@yandex-team.ru>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Link: https://patch.msgid.link/20250220110752.137639-1-jirislaby@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 36b62df568 ]
'sk->copied_seq' was updated in the tcp_eat_skb() function when the action
of a BPF program was SK_REDIRECT. For other actions, like SK_PASS, the
update logic for 'sk->copied_seq' was moved to tcp_bpf_recvmsg_parser()
to ensure the accuracy of the 'fionread' feature.
It works for a single stream_verdict scenario, as it also modified
sk_data_ready->sk_psock_verdict_data_ready->tcp_read_skb
to remove updating 'sk->copied_seq'.
However, for programs where both stream_parser and stream_verdict are
active (strparser purpose), tcp_read_sock() was used instead of
tcp_read_skb() (sk_data_ready->strp_data_ready->tcp_read_sock).
tcp_read_sock() now still updates 'sk->copied_seq', leading to duplicate
updates.
In summary, for strparser + SK_PASS, copied_seq is redundantly calculated
in both tcp_read_sock() and tcp_bpf_recvmsg_parser().
The issue causes incorrect copied_seq calculations, which prevent
correct data reads from the recv() interface in user-land.
We do not want to add new proto_ops to implement a new version of
tcp_read_sock, as this would introduce code complexity [1].
We could have added noack and copied_seq to desc, and then called
ops->read_sock. However, unfortunately, other modules didn’t fully
initialize desc to zero. So, for now, we are directly calling
tcp_read_sock_noack() in tcp_bpf.c.
[1]: https://lore.kernel.org/bpf/20241218053408.437295-1-mrpre@163.com
Fixes: e5c6de5fa0 ("bpf, sockmap: Incorrectly handling copied_seq")
Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Jiayuan Chen <mrpre@163.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://patch.msgid.link/20250122100917.49845-3-mrpre@163.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3e5796862c ]
This patch fixes a bug in TC flower filter where rules combining a
specific destination port with a source port range weren't working
correctly.
The specific case was when users tried to configure rules like:
tc filter add dev ens38 ingress protocol ip flower ip_proto udp \
dst_port 5000 src_port 2000-3000 action drop
The root cause was in the flow dissector code. While both
FLOW_DISSECTOR_KEY_PORTS and FLOW_DISSECTOR_KEY_PORTS_RANGE flags
were being set correctly in the classifier, the __skb_flow_dissect_ports()
function was only populating one of them: whichever came first in
the enum check. This meant that when the code needed both a specific
port and a port range, one of them would be left as 0, causing the
filter to not match packets as expected.
Fix it by removing the either/or logic and instead checking and
populating both key types independently when they're in use.
Fixes: 8ffb055bea ("cls_flower: Fix the behavior using port ranges with hw-offload")
Reported-by: Qiang Zhang <dtzq01@gmail.com>
Closes: https://lore.kernel.org/netdev/CAPx+-5uvFxkhkz4=j_Xuwkezjn9U6kzKTD5jz4tZ9msSJ0fOJA@mail.gmail.com/
Cc: Yoshiki Komachi <komachi.yoshiki@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250218043210.732959-2-xiyou.wangcong@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c25bdd2ac8 ]
The initial value of err is -ENOBUFS, and err is guaranteed to be
less than 0 before all goto errout. Therefore, on the error path
of errout, there is no need to repeatedly judge that err is less than 0,
and delete redundant judgments to make the code more concise.
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: becbd5850c ("neighbour: use RCU protection in __neigh_notify()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8ac412a336 ]
MEM_WRITE attribute is defined as: "Non-presence of MEM_WRITE means that
MEM is only being read". bpf_load_hdr_opt() both reads and writes from
its arg2 - void *search_res.
This matters a lot for the next commit where we more precisely track
stack accesses. Without this annotation, the verifier will make false
assumptions about the contents of memory written to by helpers and
possibly prune valid branches.
Fixes: 6fad274f06 ("bpf: Add MEM_WRITE attribute")
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Link: https://lore.kernel.org/r/730e45f8c39be2a5f3d8c4406cceca9d574cbf14.1736886479.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d1f9f79fa2 ]
The following problem was encountered during stability test:
(NULL net_device): NAPI poll function process_backlog+0x0/0x530 \
returned 1, exceeding its budget of 0.
------------[ cut here ]------------
list_add double add: new=ffff88905f746f48, prev=ffff88905f746f48, \
next=ffff88905f746e40.
WARNING: CPU: 18 PID: 5462 at lib/list_debug.c:35 \
__list_add_valid_or_report+0xf3/0x130
CPU: 18 UID: 0 PID: 5462 Comm: ping Kdump: loaded Not tainted 6.13.0-rc7+
RIP: 0010:__list_add_valid_or_report+0xf3/0x130
Call Trace:
? __warn+0xcd/0x250
? __list_add_valid_or_report+0xf3/0x130
enqueue_to_backlog+0x923/0x1070
netif_rx_internal+0x92/0x2b0
__netif_rx+0x15/0x170
loopback_xmit+0x2ef/0x450
dev_hard_start_xmit+0x103/0x490
__dev_queue_xmit+0xeac/0x1950
ip_finish_output2+0x6cc/0x1620
ip_output+0x161/0x270
ip_push_pending_frames+0x155/0x1a0
raw_sendmsg+0xe13/0x1550
__sys_sendto+0x3bf/0x4e0
__x64_sys_sendto+0xdc/0x1b0
do_syscall_64+0x5b/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The reproduction command is as follows:
sysctl -w net.core.dev_weight=0
ping 127.0.0.1
This is because when the napi's weight is set to 0, process_backlog() may
return 0 and clear the NAPI_STATE_SCHED bit of napi->state, causing this
napi to be re-polled in net_rx_action() until __do_softirq() times out.
Since the NAPI_STATE_SCHED bit has been cleared, napi_schedule_rps() can
be retriggered in enqueue_to_backlog(), causing this issue.
Making the napi's weight always non-zero solves this problem.
Triggering this issue requires system-wide admin (setting is
not namespaced).
Fixes: e387660545 ("[NET]: Fix sysctl net.core.dev_weight")
Fixes: 3d48b53fb2 ("net: dev_weight: TX/RX orthogonality")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Link: https://patch.msgid.link/20250116143053.4146855-1-liujian56@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fd4f101edb ]
Many (struct pernet_operations)->exit_batch() methods have
to acquire rtnl.
In presence of rtnl mutex pressure, this makes cleanup_net()
very slow.
This patch adds a new exit_batch_rtnl() method to reduce
number of rtnl acquisitions from cleanup_net().
exit_batch_rtnl() handlers are called while rtnl is locked,
and devices to be killed can be queued in a list provided
as their second argument.
A single unregister_netdevice_many() is called right
before rtnl is released.
exit_batch_rtnl() handlers are called before ->exit() and
->exit_batch() handlers.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Antoine Tenart <atenart@kernel.org>
Link: https://lore.kernel.org/r/20240206144313.2050392-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 46841c7053 ("gtp: Use for_each_netdev_rcu() in gtp_genl_dump_pdp().")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 76201b5979 ]
Passing a sufficient amount of imix entries leads to invalid access to the
pkt_dev->imix_entries array because of the incorrect boundary check.
UBSAN: array-index-out-of-bounds in net/core/pktgen.c:874:24
index 20 is out of range for type 'imix_pkt [20]'
CPU: 2 PID: 1210 Comm: bash Not tainted 6.10.0-rc1 #121
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
<TASK>
dump_stack_lvl lib/dump_stack.c:117
__ubsan_handle_out_of_bounds lib/ubsan.c:429
get_imix_entries net/core/pktgen.c:874
pktgen_if_write net/core/pktgen.c:1063
pde_write fs/proc/inode.c:334
proc_reg_write fs/proc/inode.c:346
vfs_write fs/read_write.c:593
ksys_write fs/read_write.c:644
do_syscall_64 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe arch/x86/entry/entry_64.S:130
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 52a62f8603 ("pktgen: Parse internet mix (imix) input")
Signed-off-by: Artem Chernyshev <artem.chernyshev@red-soft.ru>
[ fp: allow to fill the array completely; minor changelog cleanup ]
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b3af60928a ]
As pointed out in the original comment, lookup in sockmap can return a TCP
ESTABLISHED socket. Such TCP socket may have had SO_ATTACH_REUSEPORT_EBPF
set before it was ESTABLISHED. In other words, a non-NULL sk_reuseport_cb
does not imply a non-refcounted socket.
Drop sk's reference in both error paths.
unreferenced object 0xffff888101911800 (size 2048):
comm "test_progs", pid 44109, jiffies 4297131437
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
80 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 9336483b):
__kmalloc_noprof+0x3bf/0x560
__reuseport_alloc+0x1d/0x40
reuseport_alloc+0xca/0x150
reuseport_attach_prog+0x87/0x140
sk_reuseport_attach_bpf+0xc8/0x100
sk_setsockopt+0x1181/0x1990
do_sock_setsockopt+0x12b/0x160
__sys_setsockopt+0x7b/0xc0
__x64_sys_setsockopt+0x1b/0x30
do_syscall_64+0x93/0x180
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Fixes: 64d85290d7 ("bpf: Allow bpf_map_lookup_elem for SOCKMAP and SOCKHASH")
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20250110-reuseport-memleak-v1-1-fa1ddab0adfe@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 6fad274f06 upstream.
Add a MEM_WRITE attribute for BPF helper functions which can be used in
bpf_func_proto to annotate an argument type in order to let the verifier
know that the helper writes into the memory passed as an argument. In
the past MEM_UNINIT has been (ab)used for this function, but the latter
merely tells the verifier that the passed memory can be uninitialized.
There have been bugs with overloading the latter but aside from that
there are also cases where the passed memory is read + written which
currently cannot be expressed, see also 4b3786a6c5 ("bpf: Zero former
ARG_PTR_TO_{LONG,INT} args in case of error").
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20241021152809.33343-1-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: BRUNO VERNAY <bruno.vernay@se.com>
Signed-off-by: Hugo SIMELIERE <hsimeliere.opensource@witekio.com>
Stable-dep-of: 8ea607330a ("bpf: Fix overloading of MEM_UNINIT's meaning")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 68e068cabd ]
The blamed commit disabled hardware offoad of IPv6 packets with
extension headers on devices that advertise NETIF_F_IPV6_CSUM,
based on the definition of that feature in skbuff.h:
* * - %NETIF_F_IPV6_CSUM
* - Driver (device) is only able to checksum plain
* TCP or UDP packets over IPv6. These are specifically
* unencapsulated packets of the form IPv6|TCP or
* IPv6|UDP where the Next Header field in the IPv6
* header is either TCP or UDP. IPv6 extension headers
* are not supported with this feature. This feature
* cannot be set in features for a device with
* NETIF_F_HW_CSUM also set. This feature is being
* DEPRECATED (see below).
The change causes skb_warn_bad_offload to fire for BIG TCP
packets.
[ 496.310233] WARNING: CPU: 13 PID: 23472 at net/core/dev.c:3129 skb_warn_bad_offload+0xc4/0xe0
[ 496.310297] ? skb_warn_bad_offload+0xc4/0xe0
[ 496.310300] skb_checksum_help+0x129/0x1f0
[ 496.310303] skb_csum_hwoffload_help+0x150/0x1b0
[ 496.310306] validate_xmit_skb+0x159/0x270
[ 496.310309] validate_xmit_skb_list+0x41/0x70
[ 496.310312] sch_direct_xmit+0x5c/0x250
[ 496.310317] __qdisc_run+0x388/0x620
BIG TCP introduced an IPV6_TLV_JUMBO IPv6 extension header to
communicate packet length, as this is an IPv6 jumbogram. But, the
feature is only enabled on devices that support BIG TCP TSO. The
header is only present for PF_PACKET taps like tcpdump, and not
transmitted by physical devices.
For this specific case of extension headers that are not
transmitted, return to the situation before the blamed commit
and support hardware offload.
ipv6_has_hopopt_jumbo() tests not only whether this header is present,
but also that it is the only extension header before a terminal (L4)
header.
Fixes: 04c20a9356 ("net: skip offload for NETIF_F_IPV6_CSUM if ipv6 header contains extension")
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Eric Dumazet <edumazet@google.com>
Closes: https://lore.kernel.org/netdev/CANn89iK1hdC3Nt8KPhOtTF8vCPc1AHDCtse_BTNki1pWxAByTQ@mail.gmail.com/
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250101164909.1331680-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9ecc4d858b ]
skb_network_offset() and skb_transport_offset() can be negative when
they are called after we pull the transport header, for example, when
we use eBPF sockmap at the point of ->sk_data_ready().
__bpf_skb_min_len() uses an unsigned int to get these offsets, this
leads to a very large number which then causes bpf_skb_change_tail()
failed unexpectedly.
Fix this by using a signed int to get these offsets and ensure the
minimum is at least zero.
Fixes: 5293efe62d ("bpf: add bpf_skb_change_tail helper")
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20241213034057.246437-2-xiyou.wangcong@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d888b7af7c ]
When we do sk_psock_verdict_apply->sk_psock_skb_ingress, an sk_msg will
be created out of the skb, and the rmem accounting of the sk_msg will be
handled by the skb.
For skmsgs in __SK_REDIRECT case of tcp_bpf_send_verdict, when redirecting
to the ingress of a socket, although we sk_rmem_schedule and add sk_msg to
the ingress_msg of sk_redir, we do not update sk_rmem_alloc. As a result,
except for the global memory limit, the rmem of sk_redir is nearly
unlimited. Thus, add sk_rmem_alloc related logic to limit the recv buffer.
Since the function sk_msg_recvmsg and __sk_psock_purge_ingress_msg are
used in these two paths. We use "msg->skb" to test whether the sk_msg is
skb backed up. If it's not, we shall do the memory accounting explicitly.
Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Zijian Zhang <zijianzhang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20241210012039.1669389-3-zijianzhang@bytedance.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 75e072a390 upstream.
Consider a sockmap entry being updated with the same socket:
osk = stab->sks[idx];
sock_map_add_link(psock, link, map, &stab->sks[idx]);
stab->sks[idx] = sk;
if (osk)
sock_map_unref(osk, &stab->sks[idx]);
Due to sock_map_unref(), which invokes sock_map_del_link(), all the
psock's links for stab->sks[idx] are torn:
list_for_each_entry_safe(link, tmp, &psock->link, list) {
if (link->link_raw == link_raw) {
...
list_del(&link->list);
sk_psock_free_link(link);
}
}
And that includes the new link sock_map_add_link() added just before
the unref.
This results in a sockmap holding a socket, but without the respective
link. This in turn means that close(sock) won't trigger the cleanup,
i.e. a closed socket will not be automatically removed from the sockmap.
Stop tearing the links when a matching link_raw is found.
Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20241202-sockmap-replace-v1-1-1e88579e7bd5@rbox.co
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 024ee930cb ]
Traffic redirected by bpf_redirect_peer() (used by recent CNIs like Cilium)
is not accounted for in the RX stats of supported devices (that is, veth
and netkit), confusing user space metrics collectors such as cAdvisor [0],
as reported by Youlun.
Fix it by calling dev_sw_netstats_rx_add() in skb_do_redirect(), to update
RX traffic counters. Devices that support ndo_get_peer_dev _must_ use the
@tstats per-CPU counters (instead of @lstats, or @dstats).
To make this more fool-proof, error out when ndo_get_peer_dev is set but
@tstats are not selected.
[0] Specifically, the "container_network_receive_{byte,packet}s_total"
counters are affected.
Fixes: 9aa1206e8f ("bpf: Add redirect_peer helper")
Reported-by: Youlun Zhang <zhangyoulun@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20231114004220.6495-6-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Jiayuan Chen
Jakub Kicinski
Paul Chaignon
Zijun Hu
Kuniyuki Iwashima
Peter Seiderer
Oleksij Rempel
Justin Iurman
Willem de Bruijn
Jason Xing
Mark Zhang
Lin Ma
Breno Leitao
Mohammad Heib
Philo Lu
Jiri Slaby (SUSE)
Gavrilov Ilia
Jiayuan Chen
Cong Wang
Eric Dumazet
Li Zetao
Daniel Xu
Liu Jian
Artem Chernyshev
Michal Luczaj
Daniel Borkmann
Cong Wang
Zijian Zhang
Peilin Ye