linux-stable.git/net/ipv4, branch v7.1.6 Linux kernel stable tree tcp: challenge ACK for non-exact RST in SYN-RECEIVED 2026-08-03T09:26:00+00:00 Yuxiang Yang yangyx22@mails.tsinghua.edu.cn 2026-07-17T08:14:42+00:00 22cec809b048495310f206d9abbcdbbfbdce3ae3 commit a28c4fcbf774e23b4779cae468e3497a5ad1f4a1 upstream. The SYN-RECEIVED request-socket path in tcp_check_req() accepts an in-window RST without requiring SEG.SEQ to exactly match RCV.NXT. A non-exact RST therefore removes the request instead of eliciting a challenge ACK. RFC 9293 section 3.10.7.4 applies the RFC 5961 reset check in SYN-RECEIVED: an exact RST resets the connection, while a non-exact in-window RST must trigger a challenge ACK and be dropped. Apply that check before the ACK-field validation, following the RFC sequence-number, RST, then ACK processing order. Factor the per-netns challenge ACK quota out of tcp_send_challenge_ack() so request sockets can share it. Use the request socket's send_ack() callback and its own out-of-window ACK timestamp to send and rate-limit the response. Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn> Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Reported-by: Ao Wang <wangao@seu.edu.cn> Reported-by: Xuewei Feng <fengxw06@126.com> Reported-by: Qi Li <qli01@tsinghua.edu.cn> Reported-by: Ke Xu <xuke@tsinghua.edu.cn> Fixes: 282f23c6ee34 ("tcp: implement RFC 5961 3.2") Cc: stable@vger.kernel.org Signed-off-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260717081443.809393-2-yangyx22@mails.tsinghua.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a28c4fcbf774e23b4779cae468e3497a5ad1f4a1 upstream.

The SYN-RECEIVED request-socket path in tcp_check_req() accepts an
in-window RST without requiring SEG.SEQ to exactly match RCV.NXT.  A
non-exact RST therefore removes the request instead of eliciting a
challenge ACK.

RFC 9293 section 3.10.7.4 applies the RFC 5961 reset check in
SYN-RECEIVED: an exact RST resets the connection, while a non-exact
in-window RST must trigger a challenge ACK and be dropped.

Apply that check before the ACK-field validation, following the RFC
sequence-number, RST, then ACK processing order.  Factor the per-netns
challenge ACK quota out of tcp_send_challenge_ack() so request sockets
can share it.  Use the request socket's send_ack() callback and its own
out-of-window ACK timestamp to send and rate-limit the response.

Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn>
Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reported-by: Ao Wang <wangao@seu.edu.cn>
Reported-by: Xuewei Feng <fengxw06@126.com>
Reported-by: Qi Li <qli01@tsinghua.edu.cn>
Reported-by: Ke Xu <xuke@tsinghua.edu.cn>
Fixes: 282f23c6ee34 ("tcp: implement RFC 5961 3.2")
Cc: stable@vger.kernel.org
Signed-off-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260717081443.809393-2-yangyx22@mails.tsinghua.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcp: initialize standalone TCP-AO response padding 2026-08-03T09:26:00+00:00 Yizhou Zhao zhaoyz24@mails.tsinghua.edu.cn 2026-07-13T10:56:30+00:00 a859b280441fb02f64ed4037f03d5c0c34a7a595 commit e1a9d3cc11829c5414a75eb39c704f461936eb24 upstream. tcp_v4_send_ack() and tcp_v6_send_response() construct standalone TCP responses with TCP-AO options. The option length carries the actual MAC length, but the TCP header length includes the option rounded up to a four-byte boundary. tcp_ao_hash_hdr() writes the MAC only. Thus, when the MAC length is not four-byte aligned, the one to three bytes after the MAC are left uninitialized and may be transmitted. For the normal TCP-AO hashing mode, those bytes also have to be initialized before computing the MAC. Initialize only the alignment padding in the TCP-AO branches, before hashing the header. Use TCPOPT_NOP, as in the normal TCP-AO output path. This avoids adding work to non-AO TCP responses while preserving a valid authenticated header. Fixes: decde2586b34 ("net/tcp: Add TCP-AO sign to twsk") Fixes: da7dfaa6d6f7 ("net/tcp: Consistently align TCP-AO option in the header") Cc: stable@vger.kernel.org Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn> Reported-by: Ao Wang <wangao@seu.edu.cn> Reported-by: Xuewei Feng <fengxw06@126.com> Reported-by: Qi Li <qli01@tsinghua.edu.cn> Reported-by: Ke Xu <xuke@tsinghua.edu.cn> Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260713105631.8616-1-zhaoyz24@mails.tsinghua.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e1a9d3cc11829c5414a75eb39c704f461936eb24 upstream.

tcp_v4_send_ack() and tcp_v6_send_response() construct standalone TCP
responses with TCP-AO options.  The option length carries the actual MAC
length, but the TCP header length includes the option rounded up to a
four-byte boundary.

tcp_ao_hash_hdr() writes the MAC only.  Thus, when the MAC length is not
four-byte aligned, the one to three bytes after the MAC are left
uninitialized and may be transmitted.  For the normal TCP-AO hashing
mode, those bytes also have to be initialized before computing the MAC.

Initialize only the alignment padding in the TCP-AO branches, before
hashing the header.  Use TCPOPT_NOP, as in the normal TCP-AO output path.
This avoids adding work to non-AO TCP responses while preserving a valid
authenticated header.

Fixes: decde2586b34 ("net/tcp: Add TCP-AO sign to twsk")
Fixes: da7dfaa6d6f7 ("net/tcp: Consistently align TCP-AO option in the header")
Cc: stable@vger.kernel.org
Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn>
Reported-by: Ao Wang <wangao@seu.edu.cn>
Reported-by: Xuewei Feng <fengxw06@126.com>
Reported-by: Qi Li <qli01@tsinghua.edu.cn>
Reported-by: Ke Xu <xuke@tsinghua.edu.cn>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260713105631.8616-1-zhaoyz24@mails.tsinghua.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bpf, sockmap: Fix cork use-after-free in tcp_bpf_sendmsg() 2026-08-03T09:25:38+00:00 Chengfeng Ye nicoyip.dev@gmail.com 2026-07-24T10:38:56+00:00 752b1159ed5d0c48fe169a3721b96660a9822aa1 [ Upstream commit 2d66a033864e27ab8d5e44cb36f31d9d2413bee4 ] tcp_bpf_sendmsg() keeps msg_tx across sk_stream_wait_memory(), which drops and reacquires the socket lock. Its error path tries to decide whether msg_tx names the local temporary message by comparing it with the current value of psock->cork. This comparison is unsafe when two threads send on the same socket: Thread A Thread B msg_tx = psock->cork sk_msg_alloc() fails sk_stream_wait_memory() releases the socket lock acquires the socket lock completes the cork psock->cork = NULL frees the cork reacquires the socket lock msg_tx != psock->cork sk_msg_free(msg_tx) The stale cork is therefore mistaken for the local temporary message and freed again. KASAN reported: BUG: KASAN: slab-use-after-free in sk_msg_free+0x49/0x50 Read of size 4 at addr ffff88810c908800 by task poc/90 Call Trace: sk_msg_free+0x49/0x50 tcp_bpf_sendmsg+0x14f5/0x1cc0 __sys_sendto+0x32c/0x3a0 __x64_sys_sendto+0xdb/0x1b0 Allocated by task 89: __kasan_kmalloc+0x8f/0xa0 tcp_bpf_sendmsg+0x16b3/0x1cc0 Freed by task 91: __kasan_slab_free+0x43/0x70 kfree+0x131/0x3c0 tcp_bpf_sendmsg+0xec3/0x1cc0 msg_tx can only name the stack-local tmp or the shared cork. Check for tmp directly so a changed psock->cork cannot turn a shared message into an apparent local one. Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/87fr18lmzo.fsf%40cloudflare.com/ Link: https://lore.kernel.org/netdev/20260719161630.2901208-1-nicoyip.dev%40gmail.com/ [v1] Link: https://patch.msgid.link/20260724103856.3399001-1-nicoyip.dev@gmail.com Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2d66a033864e27ab8d5e44cb36f31d9d2413bee4 ]

tcp_bpf_sendmsg() keeps msg_tx across sk_stream_wait_memory(), which
drops and reacquires the socket lock.  Its error path tries to decide
whether msg_tx names the local temporary message by comparing it with
the current value of psock->cork.

This comparison is unsafe when two threads send on the same socket:

  Thread A                         Thread B
  msg_tx = psock->cork
  sk_msg_alloc() fails
  sk_stream_wait_memory()
    releases the socket lock      acquires the socket lock
                                  completes the cork
                                  psock->cork = NULL
                                  frees the cork
    reacquires the socket lock
  msg_tx != psock->cork
  sk_msg_free(msg_tx)

The stale cork is therefore mistaken for the local temporary message
and freed again.  KASAN reported:

  BUG: KASAN: slab-use-after-free in sk_msg_free+0x49/0x50
  Read of size 4 at addr ffff88810c908800 by task poc/90
  Call Trace:
   sk_msg_free+0x49/0x50
   tcp_bpf_sendmsg+0x14f5/0x1cc0
   __sys_sendto+0x32c/0x3a0
   __x64_sys_sendto+0xdb/0x1b0
  Allocated by task 89:
   __kasan_kmalloc+0x8f/0xa0
   tcp_bpf_sendmsg+0x16b3/0x1cc0
  Freed by task 91:
   __kasan_slab_free+0x43/0x70
   kfree+0x131/0x3c0
   tcp_bpf_sendmsg+0xec3/0x1cc0

msg_tx can only name the stack-local tmp or the shared cork. Check for
tmp directly so a changed psock->cork cannot turn a shared message into
an apparent local one.

Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/87fr18lmzo.fsf%40cloudflare.com/
Link: https://lore.kernel.org/netdev/20260719161630.2901208-1-nicoyip.dev%40gmail.com/ [v1]
Link: https://patch.msgid.link/20260724103856.3399001-1-nicoyip.dev@gmail.com
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
raw: annotate lockless match fields in raw_v4_match() 2026-08-03T09:25:36+00:00 Runyu Xiao runyu.xiao@seu.edu.cn 2026-07-16T14:29:58+00:00 74ab1e7c8b8e18a44b6644436db47537c53fe411 [ Upstream commit 18f116931f52e3c3303ad4b15ff41eb89b0e4239 ] raw_v4_match() is a lockless match helper under sk_for_each_rcu(). It still reads inet->inet_daddr, inet->inet_rcv_saddr and sk->sk_bound_dev_if with plain loads while bind, connect and bind-to-device paths can update the same match fields concurrently. Annotate only those mutable match fields in raw_v4_match(), and do so at the point of use instead of hoisting the bound-device read before the earlier short-circuit tests. Also annotate the raw bind writer and the shared IPv4 datagram connect writer used by raw sockets, so the address fields updated on bind and connect match explicit WRITE_ONCE() updates. This version intentionally leaves the shared disconnect-side IPv4 writers to follow-up cleanup and limits the writer changes here to the raw bind path and the datagram connect path directly exercised by raw sockets. Fixes: 0daf07e52709 ("raw: convert raw sockets to RCU") Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn> Link: https://patch.msgid.link/20260716142958.3064224-1-runyu.xiao@seu.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 18f116931f52e3c3303ad4b15ff41eb89b0e4239 ]

raw_v4_match() is a lockless match helper under sk_for_each_rcu(). It
still reads inet->inet_daddr, inet->inet_rcv_saddr and
sk->sk_bound_dev_if with plain loads while bind, connect and
bind-to-device paths can update the same match fields concurrently.

Annotate only those mutable match fields in raw_v4_match(), and do so
at the point of use instead of hoisting the bound-device read before
the earlier short-circuit tests.

Also annotate the raw bind writer and the shared IPv4 datagram connect
writer used by raw sockets, so the address fields updated on bind and
connect match explicit WRITE_ONCE() updates.

This version intentionally leaves the shared disconnect-side IPv4
writers to follow-up cleanup and limits the writer changes here to the
raw bind path and the datagram connect path directly exercised by raw
sockets.

Fixes: 0daf07e52709 ("raw: convert raw sockets to RCU")
Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Link: https://patch.msgid.link/20260716142958.3064224-1-runyu.xiao@seu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ipv4: icmp: fill flow parameters in icmp_route_lookup decoy lookup 2026-08-03T09:25:36+00:00 Eric Dumazet edumazet@google.com 2026-07-22T10:42:36+00:00 ee5b419cad37461a1f70cdb3541f9a428cdd3d18 [ Upstream commit 853e164c2b321f0711361bc23505aaeb7dc432c3 ] When Linux forwards a packet and needs to generate an ICMP error, icmp_route_lookup() performs a reverse-path relookup. For non-local destinations, it performs a decoy lookup to find the expected egress interface (rt2->dst.dev) before validating the path with ip_route_input(). Currently, the decoy flow structure (fl4_2) only sets .daddr = fl4_dec.saddr, leaving .saddr, .flowi4_dscp, .flowi4_proto, .flowi4_mark, .flowi4_oif, .fl4_sport, .fl4_dport, and .flowi4_uid zeroed out. When policy routing rules (such as ip rule add from $SRC lookup 100, or dscp/fwmark/ipproto/port rules, or VRF bindings) are configured: 1. The decoy lookup fails to match the policy rule because saddr and other key flow selectors are missing in fl4_2. 2. It resolves a route using the default table instead, returning an incorrect egress netdev. 3. Passing the wrong netdev to ip_route_input() causes strict reverse-path filtering (rp_filter=1) to fail, logging false-positive "martian source" warnings and causing the relookup to fail. Fix this by initializing fl4_2 from fl4_dec and: - Swapping source/destination IP addresses. - Swapping L4 ports for transport protocols with ports (TCP, UDP, SCTP, DCCP) so port-based policy routing matches correctly. Non-port protocols (such as ICMP or GRE) leave the flowi_uli union fields intact to prevent corruption. - Setting .flowi4_oif = l3mdev_master_ifindex(route_lookup_dev) to ensure VRF routing tables are respected. - Setting .flowi4_flags |= FLOWI_FLAG_ANYSRC to allow output route lookups for non-local source IP addresses. - Using __ip_route_output_key() instead of ip_route_output_key() for fl4_2 so that raw FIB routing is used without triggering spurious XFRM policy lookups on the decoy flow (the actual XFRM lookup is performed later using fl4_dec). Fixes: 415b3334a21a ("icmp: Fix regression in nexthop resolution during replies.") Reported-by: Muhammad Ziad <muhzi100@gmail.com> Closes: https://lore.kernel.org/netdev/CAOAwikA60AYKdFr_UDLyja3oU4hqyAE7uFZWqum5uRdaQsgRYg@mail.gmail.com/ Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20260722104236.2938082-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 853e164c2b321f0711361bc23505aaeb7dc432c3 ]

When Linux forwards a packet and needs to generate an ICMP error,
icmp_route_lookup() performs a reverse-path relookup. For non-local
destinations, it performs a decoy lookup to find the expected egress
interface (rt2->dst.dev) before validating the path with ip_route_input().

Currently, the decoy flow structure (fl4_2) only sets .daddr = fl4_dec.saddr,
leaving .saddr, .flowi4_dscp, .flowi4_proto, .flowi4_mark, .flowi4_oif,
.fl4_sport, .fl4_dport, and .flowi4_uid zeroed out.

When policy routing rules (such as ip rule add from $SRC lookup 100, or
dscp/fwmark/ipproto/port rules, or VRF bindings) are configured:
1. The decoy lookup fails to match the policy rule because saddr and other
   key flow selectors are missing in fl4_2.
2. It resolves a route using the default table instead, returning an incorrect
   egress netdev.
3. Passing the wrong netdev to ip_route_input() causes strict reverse-path
   filtering (rp_filter=1) to fail, logging false-positive "martian source"
   warnings and causing the relookup to fail.

Fix this by initializing fl4_2 from fl4_dec and:
- Swapping source/destination IP addresses.
- Swapping L4 ports for transport protocols with ports (TCP, UDP, SCTP, DCCP)
  so port-based policy routing matches correctly. Non-port protocols (such as
  ICMP or GRE) leave the flowi_uli union fields intact to prevent corruption.
- Setting .flowi4_oif = l3mdev_master_ifindex(route_lookup_dev) to ensure
  VRF routing tables are respected.
- Setting .flowi4_flags |= FLOWI_FLAG_ANYSRC to allow output route lookups
  for non-local source IP addresses.
- Using __ip_route_output_key() instead of ip_route_output_key() for fl4_2
  so that raw FIB routing is used without triggering spurious XFRM policy
  lookups on the decoy flow (the actual XFRM lookup is performed later using
  fl4_dec).

Fixes: 415b3334a21a ("icmp: Fix regression in nexthop resolution during replies.")
Reported-by: Muhammad Ziad <muhzi100@gmail.com>
Closes: https://lore.kernel.org/netdev/CAOAwikA60AYKdFr_UDLyja3oU4hqyAE7uFZWqum5uRdaQsgRYg@mail.gmail.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260722104236.2938082-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: gre: fix lltx regression for GRE tunnels with SEQ/CSUM 2026-08-03T09:25:36+00:00 Yun Zhou yun.zhou@windriver.com 2026-07-13T15:09:45+00:00 2bffe379023512d280337c70faeb6a8cc435db5e [ Upstream commit 675ed582c1aa4d919dd535490de08c015005c653 ] Before commit 00d066a4d4ed ("netdev_features: convert NETIF_F_LLTX to dev->lltx"), NETIF_F_LLTX was set unconditionally in both __gre_tunnel_init() and ip6gre_tnl_init_features() alongside GRE_FEATURES: dev->features |= GRE_FEATURES | NETIF_F_LLTX; When that commit converted NETIF_F_LLTX to the dev->lltx flag, it placed 'dev->lltx = true' after the SEQ/CSUM early returns instead of before them. This causes GRE/GRETAP/ip6gre tunnels with SEQ or CSUM+encap to lose lockless TX, reintroducing _xmit_lock acquisition around their ndo_start_xmit. Since GRE xmit re-enters the stack via ip_tunnel_xmit(), holding _xmit_lock risks ABBA deadlock with the underlay device. CPU0 CPU1 ---- ---- lock(&qdisc_xmit_lock_key#6); lock(&qdisc_xmit_lock_key#3); lock(&qdisc_xmit_lock_key#6); lock(&qdisc_xmit_lock_key#3); Fix by moving dev->lltx = true before the early returns in both functions, restoring the original unconditional behavior. Fixes: 00d066a4d4ed ("netdev_features: convert NETIF_F_LLTX to dev->lltx") Signed-off-by: Yun Zhou <yun.zhou@windriver.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260713150945.1779628-1-yun.zhou@windriver.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 675ed582c1aa4d919dd535490de08c015005c653 ]

Before commit 00d066a4d4ed ("netdev_features: convert NETIF_F_LLTX to
dev->lltx"), NETIF_F_LLTX was set unconditionally in both
__gre_tunnel_init() and ip6gre_tnl_init_features() alongside
GRE_FEATURES:

    dev->features |= GRE_FEATURES | NETIF_F_LLTX;

When that commit converted NETIF_F_LLTX to the dev->lltx flag, it
placed 'dev->lltx = true' after the SEQ/CSUM early returns instead
of before them. This causes GRE/GRETAP/ip6gre tunnels with SEQ or
CSUM+encap to lose lockless TX, reintroducing _xmit_lock acquisition
around their ndo_start_xmit. Since GRE xmit re-enters the stack via
ip_tunnel_xmit(), holding _xmit_lock risks ABBA deadlock with the
underlay device.

  CPU0                        CPU1
  ----                        ----
  lock(&qdisc_xmit_lock_key#6);
                              lock(&qdisc_xmit_lock_key#3);
                              lock(&qdisc_xmit_lock_key#6);
  lock(&qdisc_xmit_lock_key#3);

Fix by moving dev->lltx = true before the early returns in both
functions, restoring the original unconditional behavior.

Fixes: 00d066a4d4ed ("netdev_features: convert NETIF_F_LLTX to dev->lltx")
Signed-off-by: Yun Zhou <yun.zhou@windriver.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260713150945.1779628-1-yun.zhou@windriver.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
bpf: tcp: fix double sock release on batch realloc 2026-08-03T09:25:36+00:00 Xiang Mei (Microsoft) xmei5@asu.edu 2026-07-13T23:32:30+00:00 8a726e9585ffe7bfbfad2b5279277a00973970f3 [ Upstream commit 980a813452754f8001704744e92f7aa697c53dd3 ] bpf_iter_tcp_batch() releases the current batch via bpf_iter_tcp_put_batch(), which drops the socket refs and rewrites each slot with the socket cookie, then grows the batch. cur_sk/end_sk are kept for bpf_iter_tcp_resume(), but on realloc failure the function returns ERR_PTR() before resume runs, leaving cur_sk < end_sk over slots that now hold cookies rather than sock pointers. bpf_iter_tcp_seq_stop() then calls bpf_iter_tcp_put_batch() again and dereferences a cookie as a struct sock. Empty the batch on the failure path so stop() does not release it again. The sockets were already freed by the first bpf_iter_tcp_put_batch(), so nothing leaks, and a later read() rescans the bucket from the start instead of skipping it. The sibling GFP_NOWAIT failure path still holds real socket references and is left for stop() to release. BUG: KASAN: null-ptr-deref in __sock_gen_cookie Read of size 8 at addr 0000000000000059 by task exploit ... __sock_gen_cookie (net/core/sock_diag.c:28) bpf_iter_tcp_put_batch (net/ipv4/tcp_ipv4.c:2918) bpf_iter_tcp_seq_stop (net/ipv4/tcp_ipv4.c:3270) bpf_seq_read (kernel/bpf/bpf_iter.c:205) vfs_read (fs/read_write.c:572) ksys_read (fs/read_write.c:716) do_syscall_64 entry_SYSCALL_64_after_hwframe Kernel panic - not syncing: Fatal exception Fixes: cdec67a489d4 ("bpf: tcp: Make sure iter->batch always contains a full bucket snapshot") Reported-by: AutonomousCodeSecurity@microsoft.com Signed-off-by: Xiang Mei (Microsoft) <xmei5@asu.edu> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jordan Rife <jordan@jrife.io> Link: https://patch.msgid.link/20260713233230.3553593-1-xmei5@asu.edu Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 980a813452754f8001704744e92f7aa697c53dd3 ]

bpf_iter_tcp_batch() releases the current batch via
bpf_iter_tcp_put_batch(), which drops the socket refs and rewrites
each slot with the socket cookie, then grows the batch. cur_sk/end_sk
are kept for bpf_iter_tcp_resume(), but on realloc failure the function
returns ERR_PTR() before resume runs, leaving cur_sk < end_sk over
slots that now hold cookies rather than sock pointers.
bpf_iter_tcp_seq_stop() then calls bpf_iter_tcp_put_batch() again and
dereferences a cookie as a struct sock.

Empty the batch on the failure path so stop() does not release it
again. The sockets were already freed by the first
bpf_iter_tcp_put_batch(), so nothing leaks, and a later read() rescans
the bucket from the start instead of skipping it. The sibling
GFP_NOWAIT failure path still holds real socket references and is left
for stop() to release.

  BUG: KASAN: null-ptr-deref in __sock_gen_cookie
  Read of size 8 at addr 0000000000000059 by task exploit
   ...
   __sock_gen_cookie (net/core/sock_diag.c:28)
   bpf_iter_tcp_put_batch (net/ipv4/tcp_ipv4.c:2918)
   bpf_iter_tcp_seq_stop (net/ipv4/tcp_ipv4.c:3270)
   bpf_seq_read (kernel/bpf/bpf_iter.c:205)
   vfs_read (fs/read_write.c:572)
   ksys_read (fs/read_write.c:716)
   do_syscall_64
   entry_SYSCALL_64_after_hwframe
  Kernel panic - not syncing: Fatal exception

Fixes: cdec67a489d4 ("bpf: tcp: Make sure iter->batch always contains a full bucket snapshot")
Reported-by: AutonomousCodeSecurity@microsoft.com
Signed-off-by: Xiang Mei (Microsoft) <xmei5@asu.edu>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jordan Rife <jordan@jrife.io>
Link: https://patch.msgid.link/20260713233230.3553593-1-xmei5@asu.edu
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
nexthop: initialize extack in nh_res_bucket_migrate() 2026-08-03T09:25:33+00:00 Xiang Mei (Microsoft) xmei5@asu.edu 2026-07-13T22:15:51+00:00 18506d7263768d76ac8e057ba55a4d9da50aad66 [ Upstream commit 6347c5314cee49f364aaf2e40ff15415a57a116e ] nh_res_bucket_migrate() passes an uninitialized netlink_ext_ack to call_nexthop_res_bucket_notifiers(). When nh_notifier_res_bucket_info_init() fails (e.g. the kzalloc returns -ENOMEM), the error is propagated back before any notifier sets extack._msg, and the error path formats the stale pointer with pr_err_ratelimited("%s\n", extack._msg). With CONFIG_INIT_STACK_NONE this dereferences uninitialized stack memory: Oops: general protection fault, probably for non-canonical address ... KASAN: maybe wild-memory-access in range [...] RIP: 0010:string (lib/vsprintf.c:730) vsnprintf (lib/vsprintf.c:2945) _printk (kernel/printk/printk.c:2504) nh_res_bucket_migrate (net/ipv4/nexthop.c:1816) nh_res_table_upkeep (net/ipv4/nexthop.c:1866) rtm_new_nexthop (net/ipv4/nexthop.c:3323) rtnetlink_rcv_msg (net/core/rtnetlink.c:7076) netlink_sendmsg (net/netlink/af_netlink.c:1900) Kernel panic - not syncing: Fatal exception Zero-initialize extack so _msg is NULL on error paths that never set it. Fixes: 7c37c7e00411 ("nexthop: Implement notifiers for resilient nexthop groups") Reported-by: AutonomousCodeSecurity@microsoft.com Signed-off-by: Xiang Mei (Microsoft) <xmei5@asu.edu> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260713221551.3344650-1-xmei5@asu.edu Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 6347c5314cee49f364aaf2e40ff15415a57a116e ]

nh_res_bucket_migrate() passes an uninitialized netlink_ext_ack to
call_nexthop_res_bucket_notifiers(). When
nh_notifier_res_bucket_info_init() fails (e.g. the kzalloc returns
-ENOMEM), the error is propagated back before any notifier sets
extack._msg, and the error path formats the stale pointer with
pr_err_ratelimited("%s\n", extack._msg). With CONFIG_INIT_STACK_NONE
this dereferences uninitialized stack memory:

  Oops: general protection fault, probably for non-canonical address ...
  KASAN: maybe wild-memory-access in range [...]
  RIP: 0010:string (lib/vsprintf.c:730)
   vsnprintf (lib/vsprintf.c:2945)
   _printk (kernel/printk/printk.c:2504)
   nh_res_bucket_migrate (net/ipv4/nexthop.c:1816)
   nh_res_table_upkeep (net/ipv4/nexthop.c:1866)
   rtm_new_nexthop (net/ipv4/nexthop.c:3323)
   rtnetlink_rcv_msg (net/core/rtnetlink.c:7076)
   netlink_sendmsg (net/netlink/af_netlink.c:1900)
  Kernel panic - not syncing: Fatal exception

Zero-initialize extack so _msg is NULL on error paths that never set it.

Fixes: 7c37c7e00411 ("nexthop: Implement notifiers for resilient nexthop groups")
Reported-by: AutonomousCodeSecurity@microsoft.com
Signed-off-by: Xiang Mei (Microsoft) <xmei5@asu.edu>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260713221551.3344650-1-xmei5@asu.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
tcp: fix TIME_WAIT socket reference leak on PSP policy failure 2026-08-03T09:25:23+00:00 Eric Dumazet edumazet@google.com 2026-07-10T18:13:17+00:00 374742a961becbbfc7fbfd1382d978a05e492741 [ Upstream commit 2c1931a81122c3cdc4c89448fe0442c69e21c0d5 ] Release the TIME_WAIT socket reference and jump to discard_it upon PSP policy failure in both IPv4 and IPv6 receive paths. This prevents a memory leak of tcp_tw_bucket structures. Fixes: 659a2899a57d ("tcp: add datapath logic for PSP with inline key exchange") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com> Link: https://patch.msgid.link/20260710181317.4060230-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2c1931a81122c3cdc4c89448fe0442c69e21c0d5 ]

Release the TIME_WAIT socket reference and jump to discard_it
upon PSP policy failure in both IPv4 and IPv6 receive paths.
This prevents a memory leak of tcp_tw_bucket structures.

Fixes: 659a2899a57d ("tcp: add datapath logic for PSP with inline key exchange")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20260710181317.4060230-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ipv4: fib: free fib_alias with kfree_rcu() on insert error path 2026-08-03T09:25:21+00:00 Weiming Shi bestswngs@gmail.com 2026-07-04T17:14:21+00:00 b8d2ea75c76abcd0d72679c2f488271f573e32fb [ Upstream commit f2f152e94a67bc746afaf05a1b2702c195553112 ] fib_table_insert() publishes new_fa into the leaf's fa_list with fib_insert_alias() before calling the fib entry notifiers. When a notifier fails, the error path removes new_fa with fib_remove_alias() (hlist_del_rcu) and frees it right away with kmem_cache_free(). fib_table_lookup() walks that list under rcu_read_lock() only, so a concurrent lookup that already reached new_fa keeps reading it after the free: BUG: KASAN: slab-use-after-free in fib_table_lookup (net/ipv4/fib_trie.c:1601) Read of size 1 at addr ffff88810676d4eb by task exploit/297 Call Trace: fib_table_lookup (net/ipv4/fib_trie.c:1601) ip_route_output_key_hash_rcu (net/ipv4/route.c:2814) ip_route_output_key_hash (net/ipv4/route.c:2705) __ip4_datagram_connect (net/ipv4/datagram.c:49) udp_connect (net/ipv4/udp.c:2144) __sys_connect (net/socket.c:2167) __x64_sys_connect (net/socket.c:2173) do_syscall_64 entry_SYSCALL_64_after_hwframe which belongs to the cache ip_fib_alias of size 56 Triggering the error path needs CAP_NET_ADMIN and a registered fib notifier that can reject a route; a netdevsim device whose IPv4 FIB resource is exhausted is enough. Free new_fa with alias_free_mem_rcu(), as fib_table_delete() already does for a fib_alias removed from the trie. Fixes: a6c76c17df02 ("ipv4: Notify route after insertion to the routing table") Reported-by: Xiang Mei <xmei5@asu.edu> Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260704171421.1786806-1-bestswngs@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit f2f152e94a67bc746afaf05a1b2702c195553112 ]

fib_table_insert() publishes new_fa into the leaf's fa_list with
fib_insert_alias() before calling the fib entry notifiers. When a
notifier fails, the error path removes new_fa with fib_remove_alias()
(hlist_del_rcu) and frees it right away with kmem_cache_free().

fib_table_lookup() walks that list under rcu_read_lock() only, so a
concurrent lookup that already reached new_fa keeps reading it after the
free:

 BUG: KASAN: slab-use-after-free in fib_table_lookup (net/ipv4/fib_trie.c:1601)
 Read of size 1 at addr ffff88810676d4eb by task exploit/297
 Call Trace:
  fib_table_lookup (net/ipv4/fib_trie.c:1601)
  ip_route_output_key_hash_rcu (net/ipv4/route.c:2814)
  ip_route_output_key_hash (net/ipv4/route.c:2705)
  __ip4_datagram_connect (net/ipv4/datagram.c:49)
  udp_connect (net/ipv4/udp.c:2144)
  __sys_connect (net/socket.c:2167)
  __x64_sys_connect (net/socket.c:2173)
  do_syscall_64
  entry_SYSCALL_64_after_hwframe
 which belongs to the cache ip_fib_alias of size 56

Triggering the error path needs CAP_NET_ADMIN and a registered fib
notifier that can reject a route; a netdevsim device whose IPv4 FIB
resource is exhausted is enough.

Free new_fa with alias_free_mem_rcu(), as fib_table_delete() already
does for a fib_alias removed from the trie.

Fixes: a6c76c17df02 ("ipv4: Notify route after insertion to the routing table")
Reported-by: Xiang Mei <xmei5@asu.edu>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260704171421.1786806-1-bestswngs@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>