skb_is_err_queue() treats PACKET_OUTGOING as the sole marker for an skb
from sk_error_queue. That assumption is not true for AF_PACKET sockets:
outgoing packet taps are also delivered to packet sockets with
skb->pkt_type == PACKET_OUTGOING, but their skb->cb is owned by AF_PACKET
instead of struct sock_exterr_skb.
If such an skb is received with timestamping enabled, the generic
timestamp cmsg path can read AF_PACKET control-buffer state as
sock_exterr_skb::opt_stats. With SO_RXQ_OVFL enabled, the packet drop
counter overlaps opt_stats. An odd drop count makes the path emit
SCM_TIMESTAMPING_OPT_STATS with skb->len and skb->data. For non-linear
skbs this copies past the linear head and can trigger hardened usercopy or
disclose adjacent heap contents.
Keep skb_is_err_queue() local to net/socket.c, but make it verify that
the PACKET_OUTGOING marker is paired with the sock_rmem_free destructor
installed by sock_queue_err_skb(). AF_PACKET receive skbs use normal
receive ownership and no longer pass as error-queue skbs, while legitimate
sk_error_queue entries keep the PACKET_OUTGOING marker and sock_rmem_free
ownership.
Fixes: 8605330aac ("tcp: fix SCM_TIMESTAMPING_OPT_STATS for normal skbs")
Signed-off-by: Kyle Zeng <kylebot@openai.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260607021819.49698-1-kylebot@openai.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sashiko flags that genlmsg_reply() always consumes the skb.
The error path calls nlmsg_free(rsp) so we can't jump directly
to it. Let's not unbind, just propagate the error to the user.
This is the typical way of handling genlmsg_reply() failures.
They shouldn't happen unless user does something silly like
calling the kernel with an already-full rcvbuf.
Reported-by: Sashiko <sashiko-bot@kernel.org>
Fixes: 170aafe35c ("netdev: support binding dma-buf to netdevice")
Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
skb_gro_receive_list() calls skb_pull(skb, skb_gro_offset(skb)) without
first ensuring the data is in the linear area via pskb_may_pull(). When
the skb arrives via napi_gro_frags(), skb_headlen can be 0 (all data in
page fragments) while skb_gro_offset is non-zero (after IP+TCP header
parsing). The skb_pull() then decrements skb->len by skb_gro_offset
but skb->data_len stays unchanged, hitting BUG_ON(skb->len < skb->data_len)
in __skb_pull().
The UDP fraglist GRO path already contains this guard at
udp_offload.c:749. Adding it to skb_gro_receive_list() itself provides
centralized protection for all callers (TCP, UDP, and any future
protocols), and ensures the precondition of skb_pull() is satisfied
before it is called.
On pskb_may_pull() failure, set NAPI_GRO_CB(skb)->flush = 1 so the
skb is not held as a new GRO head and is instead delivered through the
normal receive path, matching the UDP handling.
Fixes: 8d95dc474f ("net: add code for TCP fraglist GRO")
Reported-by: HanQuan <eilaimemedsnaimel@gmail.com>
Reported-by: MingXuan <bwnie0730@outlook.com>
Signed-off-by: HanQuan <eilaimemedsnaimel@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch restricts the use of SO_ATTACH_FILTER (cBPF) on TCP sockets
to users with CAP_NET_ADMIN capability.
This blocks potential side-channel attack where an unprivileged application
attaches a filter to leak TCP sequence/acknowledgment numbers.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Tamir Shahar <tamirthesis@gmail.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Cc: Song Liu <song@kernel.org>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
UDP TX skb->destructor() is sock_wfree(), and UDP holds lock_sock()
only for UDP_CORK / MSG_MORE sendmsg().
Otherwise, sk->sk_write_space() may be read locklessly while SOCKMAP
rewrites sk->sk_write_space().
Let's use WRITE_ONCE() and READ_ONCE() for sk->sk_write_space().
Note that the write side is annotated by commit 2ef2b20cf4
("net: annotate data-races around sk->sk_{data_ready,write_space}").
Fixes: 7b98cd42b0 ("bpf: sockmap: Add UDP support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://patch.msgid.link/20260529193941.3897256-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When SKBFL_MANAGED_FRAG_REFS is set, frag pages are not refcounted but
their lifetime is controlled by the attached ubuf_info. To make a copy
of the skb_shared_info, we either should clear the flag and reference
the frags, or keep the flag and have frags unreferenced.
pskb_carve_inside_header() and pskb_carve_inside_nonlinear() don't
follow the rule and thus can leak page references. Let's clear
SKBFL_MANAGED_FRAG_REFS from the original skb to fix it. It's the
simplest way to address it, but there are more performant ways to do
that if it ever becomes a problem.
Link: https://lore.kernel.org/all/20260523085809.26331-1-nvminh232@clc.fitus.edu.vn/
Fixes: 753f1ca4e1 ("net: introduce managed frags infrastructure")
Reported-by: Minh Nguyen <minhnguyen.080505@gmail.com>
Reported-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/1e2086aa69217d7f9c8da3d38f5be7160f1b4cd1.1779993185.git.asml.silence@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When bpf_msg_push_data() inserts data in the middle of a scatterlist
entry, it splits the original entry into a left fragment and a right
fragment.
The right fragment offset is page-local, but the code advances it with
`start`, which is the message-global insertion point. For inserts into a
non-first SG entry, this over-advances the offset and leaves the split
layout inconsistent.
Advance the right fragment offset by the fragment-local delta,
`start - offset`, which matches the length removed from the front of the
original entry.
Fixes: 6fff607e2f ("bpf: sk_msg program helper bpf_msg_push_data")
Cc: stable@kernel.org
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Zhengchuan Liang <zcliangcn@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Yuqi Xu <xuyq21@lenovo.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Link: https://patch.msgid.link/8b129d10566aa3eb43f61a8f9757bcf51707d324.1779636774.git.xuyq21@lenovo.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Current release - regressions:
- netfilter: walk fib6_siblings under RCU
Previous releases - regressions:
- netlink: fix sending unassigned nsid after assigned one
- bridge: fix sleep in atomic context in netlink path
- sched: fix ethx:ingress -> ethy:egress -> ethx:ingress mirred loop
- ipv4: fix net->ipv4.sysctl_local_reserved_ports UaF
- eth: tun: free page on short-frame rejection in tun_xdp_one()
Previous releases - always broken:
- skbuff: fix missing zerocopy reference in pskb_carve helpers
- handshake: drain pending requests at net namespace exit
- ethtool:
- rss: avoid modifying the RSS context response
- module: avoid leaking a netdev ref on module flash errors
- coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES
- netfilter: fix dst corruption in same register operation
- nfc: hci: fix out-of-bounds read in HCP header parsing
- ipv6: exthdrs: refresh nh pointer after ipv6_hop_jumbo()
- eth: vti: use ip6_tnl.net in vti6_changelink().
- eth: vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
-----BEGIN PGP SIGNATURE-----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=IBwj
-----END PGP SIGNATURE-----
Merge tag 'net-7.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Paolo Abeni:
"This is again significantly bigger than the same point into the
previous cycle, but at least smaller than last week.
I'm not aware of any pending regression for the current cycle.
Including fixes from netfilter.
Current release - regressions:
- netfilter: walk fib6_siblings under RCU
Previous releases - regressions:
- netlink: fix sending unassigned nsid after assigned one
- bridge: fix sleep in atomic context in netlink path
- sched: fix ethx:ingress -> ethy:egress -> ethx:ingress mirred loop
- ipv4: fix net->ipv4.sysctl_local_reserved_ports UaF
- eth: tun: free page on short-frame rejection in tun_xdp_one()
Previous releases - always broken:
- skbuff: fix missing zerocopy reference in pskb_carve helpers
- handshake: drain pending requests at net namespace exit
- ethtool:
- rss: avoid modifying the RSS context response
- module: avoid leaking a netdev ref on module flash errors
- coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES
- netfilter: fix dst corruption in same register operation
- nfc: hci: fix out-of-bounds read in HCP header parsing
- ipv6: exthdrs: refresh nh pointer after ipv6_hop_jumbo()
- eth:
- vti: use ip6_tnl.net in vti6_changelink().
- vxlan: do not reuse cached ip_hdr() value after
skb_tunnel_check_pmtu()"
* tag 'net-7.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (94 commits)
dpll: zl3073x: make frequency monitor a per-device attribute
dpll: zl3073x: use __dpll_device_change_ntf() and remove change_work
dpll: export __dpll_device_change_ntf() for use under dpll_lock
net/handshake: Drain pending requests at net namespace exit
net/handshake: Verify file-reference balance in submit paths
net/handshake: Close the submit-side sock_hold race
net/handshake: hand off the pinned file reference to accept_doit
net/handshake: Take a long-lived file reference at submit
net/handshake: Pass negative errno through handshake_complete()
nvme-tcp: store negative errno in queue->tls_err
net/handshake: Use spin_lock_bh for hn_lock
net: skbuff: fix missing zerocopy reference in pskb_carve helpers
net: hibmcge: move dma_rmb() after dma_sync_single_for_cpu() in RX path
net: hibmcge: disable Relaxed Ordering to fix RX packet corruption
selftests/tc-testing: Add netem test case exercising loops
selftests/tc-testing: Add mirred test cases exercising loops
net/sched: act_mirred: Fix return code in early mirred redirect error paths
net/sched: act_mirred: Fix blockcast recursion bypass leading to stack overflow
net/sched: Fix ethx:ingress -> ethy:egress -> ethx:ingress mirred loop
net/sched: fix packet loop on netem when duplicate is on
...
pskb_carve_inside_header() and pskb_carve_inside_nonlinear() both copy
the old skb_shared_info header into a new buffer via memcpy(), which
includes the destructor_arg pointer (uarg) for MSG_ZEROCOPY skbs.
Neither function calls net_zcopy_get() for the new shinfo, creating an
unaccounted holder: every skb_shared_info with destructor_arg set will
call skb_zcopy_clear() once when freed, but the corresponding
net_zcopy_get() was never called for the new copy. Repeated calls
drive uarg->refcnt to zero prematurely, freeing ubuf_info_msgzc while
TX skbs still hold live destructor_arg pointers.
KASAN reports use-after-free on a freed ubuf_info_msgzc:
BUG: KASAN: slab-use-after-free in skb_release_data+0x77b/0x810
Read of size 8 at addr ffff88801574d3e8 by task poc/220
Call Trace:
skb_release_data+0x77b/0x810
kfree_skb_list_reason+0x13e/0x610
skb_release_data+0x4cd/0x810
sk_skb_reason_drop+0xf3/0x340
skb_queue_purge_reason+0x282/0x440
rds_tcp_inc_free+0x1e/0x30
rds_recvmsg+0x354/0x1780
__sys_recvmsg+0xdf/0x180
Allocated by task 219:
msg_zerocopy_realloc+0x157/0x7b0
tcp_sendmsg_locked+0x2892/0x3ba0
Freed by task 219:
ip_recv_error+0x74a/0xb10
tcp_recvmsg+0x475/0x530
The skb consuming the late access still referenced the same uarg via
shinfo->destructor_arg copied by pskb_carve_inside_nonlinear() without
a refcount bump. This has been verified to be reliably exploitable: a
working proof-of-concept achieves full root privilege escalation from
an unprivileged local user on a default kernel configuration.
The fix follows the pattern of pskb_expand_head() which has the same
memcpy/cloned structure. For pskb_carve_inside_header(), net_zcopy_get()
is placed after skb_orphan_frags() succeeds, so the orphan error path
needs no cleanup. For pskb_carve_inside_nonlinear(), net_zcopy_get() is
placed after all failure points and just before skb_release_data(), so
no error path needs cleanup at all -- matching pskb_expand_head() more
closely and avoiding the need for a balancing net_zcopy_put().
Fixes: 6fa01ccd88 ("skbuff: Add pskb_extract() helper function")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-sonnet-4-6
Signed-off-by: Minh Nguyen <minhnguyen.080505@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260526041240.329462-1-minhnguyen.080505@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
post-7.1 issues or aren't considered suitable for backporting.
All patches are singletons - please see the individual changelogs for
details.
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCahTZ2QAKCRDdBJ7gKXxA
ju+UAQDUga+l95O1iOnrraKFWvT1ghQKTgbNxGMwefHjVLLFBQD+Ln2wPfz73Ks7
H8WK0k5D0g+6lKs6tFGAALdQnTU0BAU=
=MYsv
-----END PGP SIGNATURE-----
Merge tag 'mm-hotfixes-stable-2026-05-25-16-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"13 hotfixes. 9 are for MM. 9 are cc:stable and the remaining 4 address
post-7.1 issues or aren't considered suitable for backporting.
All patches are singletons - please see the individual changelogs for
details"
* tag 'mm-hotfixes-stable-2026-05-25-16-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
Revert "mm: introduce a new page type for page pool in page type"
mm/vmalloc: do not trigger BUG() on BH disabled context
MAINTAINERS, mailmap: change email for Eugen Hristev
mm/migrate_device: fix pgtable leak in migrate_vma_insert_huge_pmd_page
kernel/fork: validate exit_signal in kernel_clone()
mm: memcontrol: propagate NMI slab stats to memcg vmstats
mm/damon/sysfs-schemes: delete tried region in regions_rmdirs()
mm/rmap: initialize nr_pages to 1 at loop start in try_to_unmap_one
zram: fix use-after-free in zram_writeback_endio
memfd: deny writeable mappings when implying SEAL_WRITE
ipc: limit next_id allocation to the valid ID range
Revert "mm/hugetlbfs: update hugetlbfs to use mmap_prepare"
MAINTAINERS: .mailmap: update after GEHC spin-off
pskb_trim_rcsum_slow() keeps CHECKSUM_COMPLETE valid by subtracting
the checksum of the bytes removed from the skb tail. That assumes the
removed bytes can be read.
io_uring zcrx skbs may contain unreadable net_iov frags. With fbnic
header/data split, small TCP/IPv4 packets can carry Ethernet padding
in such a frag. ip_rcv_core() trims the skb to iph->tot_len before TCP
sees it, and the CHECKSUM_COMPLETE adjustment then calls
skb_checksum() on the padding.
This is exposed by IPv4 because small TCP/IPv4 frames can be shorter
than the Ethernet minimum payload. TCP/IPv6 frames are large enough in
the normal zcrx path, so they do not hit the same padding trim.
Keep the existing checksum adjustment for readable skbs. If the
remaining packet is fully linear, drop CHECKSUM_COMPLETE and let the
stack validate the packet after trimming. If unreadable payload would
remain, fail the trim; the checksum cannot be adjusted without reading
the trimmed tail.
Also clear skb->unreadable when trimming removes all frags.
Fixes: 65249feb6b ("net: add support for skbs with unreadable frags")
Signed-off-by: Björn Töpel <bjorn@kernel.org>
Reviewed-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260522120643.242974-1-bjorn@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This reverts commit db359fccf2 ("mm: introduce a new page type for page
pool in page type") and a part of 735a309b4b ("net: add net_iov_init()
and use it to initialize ->page_type").
Netpp page_type'ed pages might be used in mapping so as to use @_mapcount.
However, since @page_type and @_mapcount are union'ed in struct page,
these two can't be used at the same time. Revert the commit introducing
page_type for Netpp for now.
The patch will be retried once @page_type and @_mapcount get allowed to be
used at the same time.
The revert also includes removal of @page_type initialization part
introduced by commit 735a309b4b ("net: add net_iov_init() and use it
to initialize ->page_type"), which will be restored on the retry.
Link: https://lore.kernel.org/20260515034701.17027-1-byungchul@sk.com
Fixes: db359fccf2 ("mm: introduce a new page type for page pool in page type")
Signed-off-by: Byungchul Park <byungchul@sk.com>
Reported-by: Dragos Tatulea <dtatulea@nvidia.com>
Closes: https://lore.kernel.org/all/982b9bc1-0a0a-4fc5-8e3a-3672db2b29a1@nvidia.com
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Harry Yoo (Oracle) <harry@kernel.org>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Cc: Jesper Dangaard Brouer <hawk@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Mark Bloch <mbloch@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Saeed Mahameed <saeedm@nvidia.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tariq Toukan <tariqt@nvidia.com>
Cc: Toke Hoiland-Jorgensen <toke@redhat.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
skb_gro_receive() can currently copy frags between the source and GRO
skb, without checking the zerocopy status, and in particular the
SKBFL_MANAGED_FRAG_REFS flag.
When SKBFL_MANAGED_FRAG_REFS is set, the skb doesn't hold a reference
on the pages in shinfo->frags. Appending those frags to another skb's
frags without fixing up the page refcount can lead to UAF.
When either the last skb in the GRO chain (the one we would append
frags to) or the source skb is zerocopy, don't merge the skbs.
Fixes: 753f1ca4e1 ("net: introduce managed frags infrastructure")
Reported-by: Huzaifa Sidhpurwala <huzaifas@redhat.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/c3b7f906bbfcbdfd7b4fa9d6c18a438870df85be.1779307748.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
__netpoll_send_skb() always transmits through np->dev and queues busy
packets on np->dev->npinfo->txq, but it leaves skb->dev unchanged.
Stacked callers such as DSA and macvlan can reach netpoll with skb->dev
still naming the upper device while np->dev is the lower device that
owns the netpoll state.
If the skb has to be deferred, queue_process() later dequeues it from
the lower device's txq but retries it through skb->dev. That can
re-enter the upper ndo_start_xmit path on an already transformed skb,
and if the upper device disappears before the lower txq drains the
workqueue can dereference a stale skb->dev pointer.
The buggy scenario involves two paths, with each column showing the
order within that path:
path A label: netpoll enqueue path path B label: upper-device teardown
1. Stacked xmit calls netpoll 1. Teardown unregisters the upper
with lower np->dev and upper net_device while lower npinfo
skb->dev. stays alive.
2. __netpoll_send_skb() uses 2. netdev_release() runs for the
np->dev->npinfo as the txq upper net_device.
owner.
3. Busy transmit queues the skb 3. The lower txq still owns the
on that lower txq with upper deferred skb.
skb->dev.
4. queue_process() drains the 4. queue_process() dereferences
lower txq and reads skb->dev. that stale upper skb->dev.
Normalize skb->dev to np->dev after loading np->dev from the netpoll
instance, before either the direct transmit path or the fallback enqueue.
This keeps the queued skb in the same device and txq domain as the
netpoll state that owns it.
KASAN report as below:
KASAN slab-use-after-free in queue_process+0x7c/0x480
Workqueue: events queue_process
The buggy address belongs to the object at ffff88810906c000 which belongs
to the cache kmalloc-4k of size 4096
The buggy address is located 168 bytes inside of freed 4096-byte region
[ffff88810906c000, ffff88810906d000)
Read of size 8
Call trace:
dump_stack_lvl+0x73/0xb0 (?:?)
print_report+0xd1/0x620 (?:?)
srso_alias_return_thunk+0x5/0xfbef5 (?:?)
__virt_addr_valid+0x215/0x420 (?:?)
kasan_complete_mode_report_info+0x64/0x200 (?:?)
kasan_report+0xf7/0x130 (?:?)
queue_process+0x7c/0x480 (net/core/netpoll.c:88)
kasan_check_range+0x10c/0x1c0 (?:?)
__kasan_check_read+0x15/0x20 (?:?)
process_one_work+0x8b7/0x1af0 (kernel/workqueue.c:3200)
assign_work+0x170/0x3f0 (?:?)
worker_thread+0x574/0xf10 (?:?)
_raw_spin_unlock_irqrestore+0x4b/0x60 (?:?)
trace_hardirqs_on+0x2a/0x180 (?:?)
kthread+0x2fc/0x3f0 (?:?)
ret_from_fork+0x58b/0x830 (?:?)
__switch_to+0x58e/0xe90 (?:?)
__switch_to_asm+0x39/0x70 (?:?)
ret_from_fork_asm+0x1a/0x30 (?:?)
Freed by task stack:
kasan_save_stack+0x3d/0x60 (?:?)
kasan_save_track+0x18/0x40 (?:?)
kasan_save_free_info+0x3f/0x60 (?:?)
__kasan_slab_free+0x48/0x70 (?:?)
kfree+0x20e/0x4e0 (?:?)
kvfree+0x31/0x40 (?:?)
netdev_release+0x71/0x90 (net/core/net-sysfs.c:2227)
device_release+0xd2/0x250 (?:?)
kobject_put+0x181/0x4c0 (lib/kobject.c:730)
netdev_run_todo+0x700/0x1000 (net/core/dev.c:11666)
rtnl_dellink+0x396/0xc00 (net/core/rtnetlink.c:3558)
rtnetlink_rcv_msg+0x740/0xc20 (net/core/rtnetlink.c:6897)
netlink_rcv_skb+0x147/0x3a0 (?:?)
rtnetlink_rcv+0x19/0x20 (net/core/rtnetlink.c:7021)
netlink_unicast+0x4d1/0x830 (net/netlink/af_netlink.c:1327)
netlink_sendmsg+0x840/0xe10 (net/netlink/af_netlink.c:1812)
____sys_sendmsg+0x8a7/0xb50 (?:?)
___sys_sendmsg+0x104/0x190 (?:?)
__sys_sendmsg+0x135/0x1d0 (?:?)
__x64_sys_sendmsg+0x7b/0xc0 (?:?)
x64_sys_call+0x205c/0x2130 (?:?)
do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
entry_SYSCALL_64_after_hwframe+0x77/0x7f (?:?)
Fixes: 5de4a473bd ("netpoll queue cleanup")
Signed-off-by: Zhang Cen <rollkingzzc@gmail.com>
Link: https://patch.msgid.link/20260519104647.3517990-1-rollkingzzc@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Two frag-transfer helpers (__pskb_copy_fclone() and skb_shift()) fail
to propagate the SKBFL_SHARED_FRAG bit in skb_shinfo()->flags when
moving frags from source to destination. __pskb_copy_fclone() defers
the rest of the shinfo metadata to skb_copy_header() after copying
frag descriptors, but that helper only carries over gso_{size,segs,
type} and never touches skb_shinfo()->flags; skb_shift() moves frag
descriptors directly and leaves flags untouched. As a result, the
destination skb keeps a reference to the same externally-owned or
page-cache-backed pages while reporting skb_has_shared_frag() as
false.
The mismatch is harmful in any in-place writer that uses
skb_has_shared_frag() to decide whether shared pages must be detoured
through skb_cow_data(). ESP input is one such writer (esp4.c,
esp6.c), and a single nft 'dup to <local>' rule -- or any other
nf_dup_ipv4() / xt_TEE caller -- is enough to land a pskb_copy()'d
skb in esp_input() with the marker stripped, letting an unprivileged
user write into the page cache of a root-owned read-only file via
authencesn-ESN stray writes.
Set SKBFL_SHARED_FRAG on the destination whenever frag descriptors
were actually moved from the source. skb_copy() and skb_copy_expand()
share skb_copy_header() too but linearize all paged data into freshly
allocated head storage and emerge with nr_frags == 0, so
skb_has_shared_frag() returns false on its own; they need no change.
The same omission exists in skb_gro_receive() and skb_gro_receive_list().
The former moves the incoming skb's frag descriptors into the
accumulator's last sub-skb via two paths (a direct frag-move loop and
the head_frag + memcpy path); the latter chains the incoming skb whole
onto p's frag_list. Downstream skb_segment() reads only
skb_shinfo(p)->flags, and skb_segment_list() reuses each sub-skb's
shinfo as the nskb -- both p and lp must carry the marker.
The same omission also exists in tcp_clone_payload(), which builds an
MTU probe skb by moving frag descriptors from skbs on sk_write_queue
into a freshly allocated nskb. The helper falls into the same family
and warrants the same fix for consistency; no TCP TX-side in-place
writer is currently known to reach a user page through this gap, but
a future consumer depending on the marker would regress silently.
The same omission exists in skb_segment(): the per-iteration flag
merge takes only head_skb's flag, and the inner switch that rebinds
frag_skb to list_skb on head_skb-frags exhaustion does not fold the
new frag_skb's flag into nskb. Fold frag_skb's flag at both sites
so segments drawing frags from frag_list members carry the marker.
Fixes: cef401de7b ("net: fix possible wrong checksum generation")
Fixes: f4c50a4034 ("xfrm: esp: avoid in-place decrypt on shared skb frags")
Suggested-by: Sabrina Dubroca <sd@queasysnail.net>
Suggested-by: Sultan Alsawaf <sultan@kerneltoast.com>
Suggested-by: Ben Hutchings <ben@decadent.org.uk>
Suggested-by: Lin Ma <malin89@huawei.com>
Suggested-by: Jingguo Tan <tanjingguo@huawei.com>
Suggested-by: Aaron Esau <aaron1esau@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Tested-by: Rajat Gupta <rajat.gupta@oss.qualcomm.com>
Link: https://patch.msgid.link/ageeJfJHwgzmKXbh@v4bel
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net_devmem_bind_dmabuf() trusts dmabuf->size and sg_dma_len() to be
PAGE_SIZE multiples without checking:
- tx_vec is sized dmabuf->size / PAGE_SIZE, and
net_devmem_get_niov_at() only bounds-checks virt_addr < dmabuf->size
before indexing tx_vec[virt_addr / PAGE_SIZE]. With size =
N*PAGE_SIZE + r (1 <= r < PAGE_SIZE), sendmsg() at iov_base =
N*PAGE_SIZE passes the bound check and reads tx_vec[N] -- one past.
- owner->area.num_niovs = len / PAGE_SIZE while gen_pool_add_owner()
covers the full byte len, so a non-page-multiple non-final sg
desyncs num_niovs from the gen_pool region for every later sg, on
both RX and TX.
dma-buf does not require page-aligned sizes, so the bind path has to
enforce what its own indexing assumes. Reject both with -EINVAL.
The size check is TX-only (only tx_vec is sized off dmabuf->size); the
SG-length check covers both directions.
Fixes: bd61848900 ("net: devmem: Implement TX path")
Cc: stable@vger.kernel.org
Signed-off-by: David Carlier <devnexen@gmail.com>
Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20260519203530.66310-1-devnexen@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sk_psock_strp_data_ready() already checks tls_sw_has_ctx_rx() and
defers to psock->saved_data_ready when a TLS RX context is present,
avoiding a conflict with the TLS strparser's ownership of the receive
queue (commit e91de6afa8, "bpf: Fix running sk_skb program types
with ktls").
sk_psock_verdict_data_ready() has no equivalent guard. When a socket
is inserted into a sockmap (BPF_SK_SKB_VERDICT) before TLS RX is
configured, tls_sw_strparser_arm() saves sk_psock_verdict_data_ready
as rx_ctx->saved_data_ready. On data arrival:
tls_data_ready -> tls_strp_data_ready -> tls_rx_msg_ready
-> saved_data_ready() = sk_psock_verdict_data_ready()
-> tcp_read_skb() drains sk_receive_queue via __skb_unlink()
without calling tcp_eat_skb(), so copied_seq is not advanced.
tls_strp_msg_load() then finds tcp_inq() >= full_len (stale), calls
tcp_recv_skb() on the now-empty queue, hits WARN_ON_ONCE(!first), and
returns with rx_ctx->strp.anchor.frag_list pointing at a psock-owned
(potentially freed) skb. tls_decrypt_sg() subsequently walks that
frag_list: use-after-free.
Apply the same fix as sk_psock_strp_data_ready(): if a TLS RX context
is present, call psock->saved_data_ready (sock_def_readable) to wake
recv() waiters and return immediately, leaving the receive queue
untouched. TLS retains sole ownership of the queue and decrypts the
record normally through tls_sw_recvmsg().
Fixes: ef5659280e ("bpf, sockmap: Allow skipping sk_skb parser program")
Signed-off-by: Xingwang Xiang <v3rdant.xiang@gmail.com>
Link: https://patch.msgid.link/20260517145630.20521-2-v3rdant.xiang@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
skb_try_coalesce() can attach paged frags from @from to @to. If @from
has SKBFL_SHARED_FRAG set, the resulting @to skb can contain the same
externally-owned or page-cache-backed frags, but the shared-frag marker
is currently lost.
That breaks the invariant relied on by later in-place writers. In
particular, ESP input checks skb_has_shared_frag() before deciding
whether an uncloned nonlinear skb can skip skb_cow_data(). If TCP
receive coalescing has moved shared frags into an unmarked skb, ESP can
see skb_has_shared_frag() as false and decrypt in place over page-cache
backed frags.
Propagate SKBFL_SHARED_FRAG when skb_try_coalesce() transfers paged
frags. The tailroom copy path does not need the marker because it copies
bytes into @to's linear data rather than transferring frag descriptors.
Fixes: cef401de7b ("net: fix possible wrong checksum generation")
Fixes: f4c50a4034 ("xfrm: esp: avoid in-place decrypt on shared skb frags")
Signed-off-by: William Bowling <vakzz@zellic.io>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Tested-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://patch.msgid.link/20260513041635.1289541-1-vakzz@zellic.io
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
There is netdev_lock_ops() before the NETDEV_REGISTER notifier
in register_netdevice(), so use the non-locking functions
in net_failover_slave_register().
failover_slave_register() in failover_existing_slave_register() adds lock
and unlock ops too.
Call Trace:
<TASK>
__schedule+0x30d/0x7a0
schedule+0x27/0x90
schedule_preempt_disabled+0x15/0x30
__mutex_lock.constprop.0+0x538/0x9e0
__mutex_lock_slowpath+0x13/0x20
mutex_lock+0x3b/0x50
dev_set_mtu+0x40/0xe0
net_failover_slave_register+0x24/0x280
failover_slave_register+0x103/0x1b0
failover_event+0x15e/0x210
? dropmon_net_event+0xac/0xe0
notifier_call_chain+0x5e/0xe0
raw_notifier_call_chain+0x16/0x30
call_netdevice_notifiers_info+0x52/0xa0
register_netdevice+0x5f4/0x7c0
register_netdev+0x1e/0x40
_mlx5e_probe+0xe2/0x370 [mlx5_core]
mlx5e_probe+0x59/0x70 [mlx5_core]
? __pfx_mlx5e_probe+0x10/0x10 [mlx5_core]
Fixes: 4c975fd700 ("net: hold instance lock during NETDEV_REGISTER/UP")
Signed-off-by: Faicker Mo <faicker.mo@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When in irq deferral mode (defer-hard-irqs > 0), a short enough
gro-flush timeout can trigger before NAPI_STATE_SCHED is cleared if the
last poll in busy_poll_stop() takes too long. This can have the effect
of leaving the queue stuck with interrupts disabled and no timer armed
which results in a tx timeout if there is no subsequent busypoll cycle.
To prevent this, defer the gro-flush timer arm after the last poll.
Fixes: 7fd3253a7d ("net: Introduce preferred busy-polling")
Co-developed-by: Martin Karsten <mkarsten@uwaterloo.ca>
Signed-off-by: Martin Karsten <mkarsten@uwaterloo.ca>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20260506090808.820559-2-dtatulea@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sol_tcp_sockopt() only checks if sk->sk_protocol is IPPROTO_TCP,
but RAW socket can bypass it:
socket(AF_INET, SOCK_RAW, IPPROTO_TCP)
Let's use sk_is_tcp().
Note that initially sol_tcp_sockopt() checked sk->sk_prot->setsockopt.
Fixes: 2ab42c7b87 ("bpf: Check the protocol of a sock to agree the calls to bpf_setsockopt().")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20260504210610.180150-7-kuniyu@google.com
bpf_skc_to_tcp6_sock() only checks if sk->sk_protocol is IPPROTO_TCP
and sk->sk_family is AF_INET6, but RAW socket can bypass it:
socket(AF_INET6, SOCK_RAW, IPPROTO_TCP)
Let's check sk->sk_type too.
Fixes: af7ec13833 ("bpf: Add bpf_skc_to_tcp6_sock() helper")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20260504210610.180150-6-kuniyu@google.com
bpf_skc_to_tcp_sock() only checks if sk->sk_protocol is
IPPROTO_TCP, but RAW socket can bypass it:
socket(AF_INET, SOCK_RAW, IPPROTO_TCP)
Let's use sk_is_tcp().
Fixes: 478cfbdf5f ("bpf: Add bpf_skc_to_{tcp, tcp_timewait, tcp_request}_sock() helpers")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20260504210610.180150-5-kuniyu@google.com
I was mistaken by synchronize_rcu() [1] call in netdev_name_node_alt_destroy(),
giving a false sense of RCU safety at delete times.
We have to use list_del_rcu() to not confuse potential readers
in rtnl_prop_list_size().
[1] This synchronize_rcu() call was later removed in commit 723de3ebef
("net: free altname using an RCU callback").
Fixes: 9f30831390 ("net: add rcu safety to rtnl_prop_list_size()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260502124102.499204-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
egress_dev() formats np->dev_mac via snprintf() but receives buf as
a bare char *, so it cannot derive the buffer size from the pointer. The
size argument was hardcoded to MAC_ADDR_STR_LEN (3 * ETH_ALEN - 1 = 17),
which is silly wrong in two ways:
1) misleading kernel log output on the MAC-selected target path
(np->dev_name[0] == '\0'); for example "aa:bb:cc:dd:ee:ff doesn't
exist, aborting" was logged as "aa:bb:cc:dd:ee:f doesn't exist,
aborting".
2) the second argument of snprintf is the size of the buffer, not the
size of what you want to write.
Add a bufsz parameter to egress_dev() and pass sizeof(buf) from each
caller, matching the standard snprintf() idiom and removing the
hardcoded size from the helper.
Every caller already declares "char buf[MAC_ADDR_STR_LEN + 1]" so the
formatted MAC continues to fit.
Tested by booting with
netconsole=6665@/aa:bb:cc:dd:ee:ff,6666@10.0.0.1/00:11:22:33:44:55
on a kernel without a matching device. Pre-fix dmesg shows
"aa:bb:cc:dd:ee:f doesn't exist, aborting"; post-fix shows the full
"aa:bb:cc:dd:ee:ff doesn't exist, aborting".
Fixes: f8a10bed32 ("netconsole: allow selection of egress interface via MAC address")
Cc: stable@vger.kernel.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260501-netpoll_snprintf_fix-v1-1-84b0566e6597@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rtnl_fill_vfinfo() declares struct ifla_vf_broadcast on the stack
without initialisation:
struct ifla_vf_broadcast vf_broadcast;
The struct contains a single fixed 32-byte field:
/* include/uapi/linux/if_link.h */
struct ifla_vf_broadcast {
__u8 broadcast[32];
};
The function then copies dev->broadcast into it using dev->addr_len
as the length:
memcpy(vf_broadcast.broadcast, dev->broadcast, dev->addr_len);
On Ethernet devices (the overwhelming majority of SR-IOV NICs)
dev->addr_len is 6, so only the first 6 bytes of broadcast[] are
written. The remaining 26 bytes retain whatever was previously on
the kernel stack. The full struct is then handed to userspace via:
nla_put(skb, IFLA_VF_BROADCAST,
sizeof(vf_broadcast), &vf_broadcast)
leaking up to 26 bytes of uninitialised kernel stack per VF per
RTM_GETLINK request, repeatable.
The other vf_* structs in the same function are explicitly zeroed
for exactly this reason - see the memset() calls for ivi,
vf_vlan_info, node_guid and port_guid a few lines above.
vf_broadcast was simply missed when it was added.
Reachability: any unprivileged local process can open AF_NETLINK /
NETLINK_ROUTE without capabilities and send RTM_GETLINK with an
IFLA_EXT_MASK attribute carrying RTEXT_FILTER_VF. The kernel walks
each VF and emits IFLA_VF_BROADCAST, leaking 26 bytes of stack per
VF per request. Stack residue at this call site can include return
addresses and transient sensitive data; KASAN with stack
instrumentation, or KMSAN, will flag the nla_put() when reproduced.
Zero the on-stack struct before the partial memcpy, matching the
existing pattern used for the other vf_* structs in the same
function.
Fixes: 75345f888f ("ipoib: show VF broadcast address")
Cc: stable@vger.kernel.org
Signed-off-by: Kai Zen <kai.aizen.dev@gmail.com>
Link: https://patch.msgid.link/3c506e8f936e52b57620269b55c348af05d413a2.1777557228.git.kai.aizen.dev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When page_pool_create_percpu() fails on page_pool_list(), it falls
through to its err_uninit: label, which calls page_pool_uninit().
At that point page_pool_init() has already taken two references
when the user requested PP_FLAG_ALLOW_UNREADABLE_NETMEM:
pool->mp_ops->init(pool)
static_branch_inc(&page_pool_mem_providers);
Neither is undone by page_pool_uninit(); both are only undone by
__page_pool_destroy() (success-side teardown). The error path
therefore leaks the per-provider reference taken by mp_ops->init
(io_zcrx_ifq->refs in the io_uring zcrx provider, the dmabuf
binding refcount in the devmem provider) plus one increment of
the page_pool_mem_providers static branch on every failure of
xa_alloc_cyclic() inside page_pool_list().
The leaked io_zcrx_ifq->refs in turn pins everything
io_zcrx_ifq_free() would release on cleanup: ifq->user (uid),
ifq->mm_account (mmdrop), ifq->dev (device refcount),
ifq->netdev_tracker (netdev refcount), and the rbuf region.
The leaked static branch increment forces all subsequent
page_pool_alloc_netmems() and page_pool_return_page() callers to
take the slow mp_ops branch for the lifetime of the kernel.
Reachable via the io_uring zcrx path:
io_uring_register(IORING_REGISTER_ZCRX_IFQ) /* CAP_NET_ADMIN */
-> __io_uring_register
-> io_register_zcrx
-> zcrx_register_netdev
-> netif_mp_open_rxq
-> driver ndo_queue_mem_alloc
-> page_pool_create_percpu
-> page_pool_init succeeds (mp_ops->init runs, branch++)
-> page_pool_list fails (xa_alloc_cyclic -ENOMEM)
-> goto err_uninit <-- leak
The same shape applies to the devmem dmabuf provider via
mp_dmabuf_devmem_init()/mp_dmabuf_devmem_destroy().
Restore the cleanup symmetry by moving the mp_ops->destroy() and
static_branch_dec() calls out of __page_pool_destroy() and into
page_pool_uninit(), so page_pool_uninit() is again the strict
inverse of page_pool_init(). page_pool_uninit() has only two
callers (the err_uninit: path and __page_pool_destroy()), so this
preserves the single-call invariant on the success path while
fixing the err path. The error path of page_pool_init() itself
still skips the mp_ops cleanup correctly: mp_ops->init is the
last action that takes a reference before page_pool_init() returns
0, so when it returns an error neither the refcount nor the static
branch has been touched.
Triggering the bug requires xa_alloc_cyclic() to fail with -ENOMEM,
which under normal GFP_KERNEL retry behaviour is rare. It is
deterministic under CONFIG_FAULT_INJECTION with fail_page_alloc /
xa fault injection, or under sustained memory pressure. The leak
is silent: there is no warning, and the released kernel build
continues running with a permanently-incremented static branch.
Fixes: 0f92140468 ("memory-provider: dmabuf devmem memory provider")
Signed-off-by: Hasan Basbunar <basbunarhasan@gmail.com>
Link: https://patch.msgid.link/20260428170739.34881-1-basbunarhasan@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit db359fccf2 ("mm: introduce a new page type for page pool in
page type") added a page_type field to struct net_iov at the same
offset as struct page::page_type, so that page_pool_set_pp_info() can
call __SetPageNetpp() uniformly on both pages and net_iovs.
The page-type API requires the field to hold the UINT_MAX "no type"
sentinel before a type can be set; for real struct page that invariant
is established by the page allocator on free. struct net_iov is not
allocated through the page allocator, so the field is left as zero
(io_uring zcrx, which uses __GFP_ZERO) or as slab garbage (devmem,
which uses kvmalloc_objs() without zeroing). When the page pool then
calls page_pool_set_pp_info() on a freshly-bound niov,
__SetPageNetpp()'s VM_BUG_ON_PAGE(page->page_type != UINT_MAX) fires
and the kernel BUGs. Triggered in selftests by io_uring zcrx setup
through the fbnic queue restart path:
kernel BUG at ./include/linux/page-flags.h:1062!
RIP: 0010:page_pool_set_pp_info (./include/linux/page-flags.h:1062
net/core/page_pool.c:716)
Call Trace:
<TASK>
net_mp_niov_set_page_pool (net/core/page_pool.c:1360)
io_pp_zc_alloc_netmems (io_uring/zcrx.c:1089 io_uring/zcrx.c:1110)
fbnic_fill_bdq (./include/net/page_pool/helpers.h:160
drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:906)
__fbnic_nv_restart (drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:2470
drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:2874)
fbnic_queue_start (drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:2903)
netdev_rx_queue_reconfig (net/core/netdev_rx_queue.c:137)
__netif_mp_open_rxq (net/core/netdev_rx_queue.c:234)
io_register_zcrx (io_uring/zcrx.c:818 io_uring/zcrx.c:903)
__io_uring_register (io_uring/register.c:931)
__do_sys_io_uring_register (io_uring/register.c:1029)
do_syscall_64 (arch/x86/entry/syscall_64.c:63
arch/x86/entry/syscall_64.c:94)
</TASK>
The same path is reachable through devmem dmabuf binding via
netdev_nl_bind_rx_doit() -> net_devmem_bind_dmabuf_to_queue().
Add a net_iov_init() helper that stamps ->owner, ->type and the
->page_type sentinel, and use it from both the devmem and io_uring
zcrx niov init loops.
Fixes: db359fccf2 ("mm: introduce a new page type for page pool in page type")
Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Acked-by: Byungchul Park <byungchul@sk.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://patch.msgid.link/20260428025320.853452-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netpoll_setup() decides whether to auto-populate the local source
address by testing np->local_ip.ip, which only inspects the first 4
bytes of the union inet_addr storage.
For an IPv6 netpoll whose caller-supplied local address has a zero
high-32 bits (::1, ::<suffix>, IPv4-mapped ::ffff:a.b.c.d, etc.), this
misdetects the address as unset (which they are not, but the first
4 bytes are empty), calls netpoll_take_ipv6() and overwrites it with
whatever matching link-local/global address the device happens to expose
first.
Introduce a helper netpoll_local_ip_unset() that picks the correct
family-aware test (ipv6_addr_any() for IPv6, !.ip for IPv4) and use it
from netpoll_setup().
Reproducer is something like:
echo "::2" > local_ip
echo 1 > enabled
cat local_ip
# before this fix: 2001:db8::1 (caller-supplied ::2 was clobbered)
# after this fix: ::2
Fixes: b7394d2429 ("netpoll: prepare for ipv6")
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260424-netpoll_fix-v1-1-3a55348c625f@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
neigh_xmit always releases the skb, except when no neighbour table is
found. But even the first added user of neigh_xmit (mpls) relied on
neigh_xmit to release the skb (or queue it for tx).
sashiko reported:
If neigh_xmit() is called with an uninitialized neighbor table (for
example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT
and bypasses its internal out_kfree_skb error path. Because the return
value of neigh_xmit() is ignored here, does this leak the SKB?
Assume full ownership and remove the last code path that doesn't
xmit or free skb.
Fixes: 4fd3d7d9e8 ("neigh: Add helper function neigh_xmit")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260424145843.74055-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Call check_and_init_map_value() after the copy_map_value() to zero out
special field regions. diag_get() copies sk_local_storage map values
into a netlink message using copy_map_value{_locked}(), which
intentionally skip special fields. However, the destination buffer from
nla_reserve_64bit() is not zeroed and the skipped regions contain
uninitialized skb data can be sent to userspace.
Fixes: 1ed4d92458 ("bpf: INET_DIAG support in bpf_sk_storage")
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20260423222356.155387-1-ameryhung@gmail.com
Old code like amateur radio and NFC have long been a burden
to core networking developers. syzbot loves to find bugs
in BKL-era code, and noobs try to fix them.
If we want to have a fighting chance of surviving the LLM-pocalypse
this code needs to find a dedicated owner or get deleted.
We've talked about these deletions multiple times in the past
and every time someone wanted the code to stay. It is never
very clear to me how many of those people actually use the code
vs are just nostalgic to see it go. Amateur radio did have
occasional users (or so I think) but most users switched
to user space implementations since its all super slow stuff.
Nobody stepped up to maintain the kernel code.
We were lucky enough to find someone who wants to help with NFC
so we're giving that a chance. Let's try to put the rest of
this code behind us.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=3vMU
-----END PGP SIGNATURE-----
Merge tag 'net-deletions' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking deletions from Jakub Kicinski:
"Delete some obsolete networking code
Old code like amateur radio and NFC have long been a burden to core
networking developers. syzbot loves to find bugs in BKL-era code, and
noobs try to fix them.
If we want to have a fighting chance of surviving the LLM-pocalypse
this code needs to find a dedicated owner or get deleted. We've talked
about these deletions multiple times in the past and every time
someone wanted the code to stay. It is never very clear to me how many
of those people actually use the code vs are just nostalgic to see it
go. Amateur radio did have occasional users (or so I think) but most
users switched to user space implementations since its all super slow
stuff. Nobody stepped up to maintain the kernel code.
We were lucky enough to find someone who wants to help with NFC so
we're giving that a chance. Let's try to put the rest of this code
behind us"
* tag 'net-deletions' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next:
drivers: net: 8390: wd80x3: Remove this driver
drivers: net: 8390: ultra: Remove this driver
drivers: net: 8390: AX88190: Remove this driver
drivers: net: fujitsu: fmvj18x: Remove this driver
drivers: net: smsc: smc91c92: Remove this driver
drivers: net: smsc: smc9194: Remove this driver
drivers: net: amd: nmclan: Remove this driver
drivers: net: amd: lance: Remove this driver
drivers: net: 3com: 3c589: Remove this driver
drivers: net: 3com: 3c574: Remove this driver
drivers: net: 3com: 3c515: Remove this driver
drivers: net: 3com: 3c509: Remove this driver
net: packetengines: remove obsolete yellowfin driver and vendor dir
net: packetengines: remove obsolete hamachi driver
net: remove unused ATM protocols and legacy ATM device drivers
net: remove ax25 and amateur radio (hamradio) subsystem
net: remove ISDN subsystem and Bluetooth CMTP
caif: remove CAIF NETWORK LAYER
When tot_len is not provided by the user, bpf_skb_fib_lookup()
resolves the FIB result's output device via dev_get_by_index_rcu()
to check skb forwardability and fill in mtu_result. The returned
pointer is dereferenced without a NULL check. If the device is
concurrently unregistered, dev_get_by_index_rcu() returns NULL and
is_skb_forwardable() crashes at dev->flags:
KASAN: null-ptr-deref in range
[0x00000000000000b0-0x00000000000000b7]
Call Trace:
is_skb_forwardable (include/linux/netdevice.h:4365)
bpf_skb_fib_lookup (net/core/filter.c:6446)
bpf_prog_test_run_skb (net/bpf/test_run.c)
__sys_bpf (kernel/bpf/syscall.c)
Add the missing NULL check, returning -ENODEV to be consistent
with how bpf_ipv4_fib_lookup() and bpf_ipv6_fib_lookup() handle
the same condition.
Fixes: 4f74fede40 ("bpf: Add mtu checking to FIB forwarding helper")
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://patch.msgid.link/20260423183831.1325480-2-bestswngs@gmail.com
bpf_selem_unlink_nofail() sets SDATA(selem)->smap to NULL before
removing the selem from the storage hlist. A concurrent RCU reader in
bpf_sk_storage_clone() can observe the selem still on the list with
smap already NULL, causing a NULL pointer dereference.
general protection fault, probably for non-canonical address 0xdffffc000000000a:
KASAN: null-ptr-deref in range [0x0000000000000050-0x0000000000000057]
RIP: 0010:bpf_sk_storage_clone+0x1cd/0xaa0 net/core/bpf_sk_storage.c:174
Call Trace:
<IRQ>
sk_clone+0xfed/0x1980 net/core/sock.c:2591
inet_csk_clone_lock+0x30/0x760 net/ipv4/inet_connection_sock.c:1222
tcp_create_openreq_child+0x35/0x2680 net/ipv4/tcp_minisocks.c:571
tcp_v4_syn_recv_sock+0x123/0xf90 net/ipv4/tcp_ipv4.c:1729
tcp_check_req+0x8e1/0x2580 include/net/tcp.h:855
tcp_v4_rcv+0x1845/0x3b80 net/ipv4/tcp_ipv4.c:2347
Add a NULL check for smap in bpf_sk_storage_clone().
bpf_sk_storage_diag_put_all() has the same issue. Add a NULL check
and pass the validated smap directly to diag_get(), which is refactored
to take smap as a parameter instead of reading it internally.
bpf_sk_storage_diag_put() uses diag->maps[i] which is always valid
under its refcount, so diag->maps[i] is passed directly to diag_get().
Fixes: 5d800f87d0 ("bpf: Support lockless unlink when freeing map or local storage")
Reported-by: Xiang Mei <xmei5@asu.edu>
Acked-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20260422065411.1007737-2-bestswngs@gmail.com
Steady stream of fixes. Last two weeks feel comparable to the two
weeks before the merge window. Lots of AI-aided bug discovery.
A newer big source is Sashiko/Gemini (Roman Gushchin's system),
which points out issues in existing code during patch review
(maybe 25% of fixes here likely originating from Sashiko).
Nice thing is these are often fixed by the respective maintainers,
not drive-bys.
Current release - new code bugs:
- kconfig: MDIO_PIC64HPSC should depend on ARCH_MICROCHIP
Previous releases - regressions:
- add async ndo_set_rx_mode and switch drivers which we promised
to be called under the per-netdev mutex to it
- dsa: remove duplicate netdev_lock_ops() for conduit ethtool ops
- hv_sock: report EOF instead of -EIO for FIN
- vsock/virtio: fix MSG_PEEK calculation on bytes to copy
Previous releases - always broken:
- ipv6: fix possible UAF in icmpv6_rcv()
- icmp: validate reply type before using icmp_pointers
- af_unix: drop all SCM attributes for SOCKMAP
- netfilter: fix a number of bugs in the osf (OS fingerprinting)
- eth: intel: fix timestamp interrupt configuration for E825C
Misc:
- bunch of data-race annotations
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=knNy
-----END PGP SIGNATURE-----
Merge tag 'net-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from Netfilter.
Steady stream of fixes. Last two weeks feel comparable to the two
weeks before the merge window. Lots of AI-aided bug discovery. A newer
big source is Sashiko/Gemini (Roman Gushchin's system), which points
out issues in existing code during patch review (maybe 25% of fixes
here likely originating from Sashiko). Nice thing is these are often
fixed by the respective maintainers, not drive-bys.
Current release - new code bugs:
- kconfig: MDIO_PIC64HPSC should depend on ARCH_MICROCHIP
Previous releases - regressions:
- add async ndo_set_rx_mode and switch drivers which we promised to
be called under the per-netdev mutex to it
- dsa: remove duplicate netdev_lock_ops() for conduit ethtool ops
- hv_sock: report EOF instead of -EIO for FIN
- vsock/virtio: fix MSG_PEEK calculation on bytes to copy
Previous releases - always broken:
- ipv6: fix possible UAF in icmpv6_rcv()
- icmp: validate reply type before using icmp_pointers
- af_unix: drop all SCM attributes for SOCKMAP
- netfilter: fix a number of bugs in the osf (OS fingerprinting)
- eth: intel: fix timestamp interrupt configuration for E825C
Misc:
- bunch of data-race annotations"
* tag 'net-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (148 commits)
rxrpc: Fix error handling in rxgk_extract_token()
rxrpc: Fix re-decryption of RESPONSE packets
rxrpc: Fix rxrpc_input_call_event() to only unshare DATA packets
rxrpc: Fix missing validation of ticket length in non-XDR key preparsing
rxgk: Fix potential integer overflow in length check
rxrpc: Fix conn-level packet handling to unshare RESPONSE packets
rxrpc: Fix potential UAF after skb_unshare() failure
rxrpc: Fix rxkad crypto unalignment handling
rxrpc: Fix memory leaks in rxkad_verify_response()
net: rds: fix MR cleanup on copy error
m68k: mvme147: Make me the maintainer
net: txgbe: fix firmware version check
selftests/bpf: check epoll readiness during reuseport migration
tcp: call sk_data_ready() after listener migration
vhost_net: fix sleeping with preempt-disabled in vhost_net_busy_poll()
ipv6: Cap TLV scan in ip6_tnl_parse_tlv_enc_lim
tipc: fix double-free in tipc_buf_append()
llc: Return -EINPROGRESS from llc_ui_connect()
ipv4: icmp: validate reply type before using icmp_pointers
selftests/net: packetdrill: cover RFC 5961 5.2 challenge ACK on both edges
...
A BPF TCP congestion control program can call bpf_setsockopt() from
its callbacks. In current kernels, if it calls
bpf_setsockopt(TCP_NODELAY) from cwnd_event_tx_start(), the call can
re-enter the TCP transmit path before the outer tcp_transmit_skb()
has completed and advanced the send head.
This can re-trigger CA_EVENT_TX_START and lead to unbounded recursion:
tcp_transmit_skb()
-> tcp_event_data_sent()
-> tcp_ca_event(sk, CA_EVENT_TX_START)
-> cwnd_event_tx_start()
-> bpf_setsockopt(TCP_NODELAY)
-> tcp_push_pending_frames()
-> tcp_write_xmit()
-> tcp_transmit_skb()
This leads to unbounded recursion and can overflow the kernel stack.
Reject TCP_NODELAY with -EOPNOTSUPP for bpf-tcp-cc by introducing
a dedicated setsockopt proto for BPF_PROG_TYPE_STRUCT_OPS TCP
congestion control programs. To keep it simple, all tcp-cc ops is
rejected for TCP_NODELAY.
Fixes: 7e41df5dbb ("bpf: Add a few optnames to bpf_setsockopt")
Suggested-by: Martin KaFai Lau <martin.lau@linux.dev>
Signed-off-by: KaFai Wan <kafai.wan@linux.dev>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://patch.msgid.link/20260421155804.135786-3-kafai.wan@linux.dev
A BPF_SOCK_OPS program can enable
BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG and then call
bpf_setsockopt(TCP_NODELAY) from BPF_SOCK_OPS_HDR_OPT_LEN_CB or
BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
In these callbacks, bpf_setsockopt(TCP_NODELAY) can reach
__tcp_sock_set_nodelay(), which can call tcp_push_pending_frames().
>From BPF_SOCK_OPS_HDR_OPT_LEN_CB, tcp_push_pending_frames() can call
tcp_current_mss(), which calls tcp_established_options() and re-enters
bpf_skops_hdr_opt_len().
BPF_SOCK_OPS_HDR_OPT_LEN_CB
-> bpf_setsockopt(TCP_NODELAY)
-> tcp_push_pending_frames()
-> tcp_current_mss()
-> tcp_established_options()
-> bpf_skops_hdr_opt_len()
-> BPF_SOCK_OPS_HDR_OPT_LEN_CB
>From BPF_SOCK_OPS_WRITE_HDR_OPT_CB, tcp_push_pending_frames() can call
tcp_write_xmit(), which calls tcp_transmit_skb(). That path recomputes
header option length through tcp_established_options() and
bpf_skops_hdr_opt_len() before re-entering bpf_skops_write_hdr_opt().
BPF_SOCK_OPS_WRITE_HDR_OPT_CB
-> bpf_setsockopt(TCP_NODELAY)
-> tcp_push_pending_frames()
-> tcp_write_xmit()
-> tcp_transmit_skb()
-> tcp_established_options()
-> bpf_skops_hdr_opt_len()
-> bpf_skops_write_hdr_opt()
-> BPF_SOCK_OPS_WRITE_HDR_OPT_CB
This leads to unbounded recursion and can overflow the kernel stack.
Reject TCP_NODELAY with -EOPNOTSUPP in bpf_sock_ops_setsockopt()
when bpf_setsockopt() is called from
BPF_SOCK_OPS_HDR_OPT_LEN_CB or BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
Fixes: 7e41df5dbb ("bpf: Add a few optnames to bpf_setsockopt")
Closes: https://lore.kernel.org/bpf/d1d523c9-6901-4454-a183-94462b8f3e4e@std.uestc.edu.cn/
Reported-by: Quan Sun <2022090917019@std.uestc.edu.cn>
Reported-by: Yinhao Hu <dddddd@hust.edu.cn>
Reported-by: Kaiyan Mei <M202472210@hust.edu.cn>
Signed-off-by: KaFai Wan <kafai.wan@linux.dev>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://patch.msgid.link/20260421155804.135786-2-kafai.wan@linux.dev
Now that all in-tree ops-locked drivers have been converted to
ndo_set_rx_mode_async, add a warning in register_netdevice to catch
any remaining or newly added drivers that use ndo_set_rx_mode with
ops locking. This ensures future driver authors are guided toward
the async path.
Also route ops-locked devices through netdev_rx_mode_work even if they
lack rx_mode NDOs, to ensure netdev_ops_assert_locked() does not fire
on the legacy path where only RTNL is held.
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20260416185712.2155425-14-sdf@fomichev.me
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Move unicast promiscuity tracking into netdev_rx_mode_work so it runs
under netdev_ops_lock instead of under the addr_lock spinlock. This
is required because __dev_set_promiscuity calls dev_change_rx_flags
and __dev_notify_flags, both of which may need to sleep.
Change ASSERT_RTNL() to netdev_ops_assert_locked() in
__dev_set_promiscuity, netif_set_allmulti and __dev_change_flags
since these are now called from the work queue under the ops lock.
Link: https://lore.kernel.org/netdev/20260214033859.43857-1-jiayuan.chen@linux.dev/
Fixes: 78cd408356 ("net: add missing instance lock to dev_set_promiscuity")
Reported-by: syzbot+2b3391f44313b3983e91@syzkaller.appspotmail.com
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20260416185712.2155425-5-sdf@fomichev.me
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add a per-device netdev_hw_addr_list cache (rx_mode_addr_cache) that
allows __hw_addr_list_snapshot() and __hw_addr_list_reconcile() to
reuse previously allocated entries instead of hitting GFP_ATOMIC on
every snapshot cycle.
snapshot pops entries from the cache when available, falling back to
__hw_addr_create(). reconcile splices both snapshot lists back into
the cache via __hw_addr_splice(). The cache is flushed in
free_netdev().
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20260416185712.2155425-4-sdf@fomichev.me
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add ndo_set_rx_mode_async callback that drivers can implement instead
of the legacy ndo_set_rx_mode. The legacy callback runs under the
netif_addr_lock spinlock with BHs disabled, preventing drivers from
sleeping. The async variant runs from a work queue with rtnl_lock and
netdev_lock_ops held, in fully sleepable context.
When __dev_set_rx_mode() sees ndo_set_rx_mode_async, it schedules
netdev_rx_mode_work instead of calling the driver inline. The work
function takes two snapshots of each address list (uc/mc) under
the addr_lock, then drops the lock and calls the driver with the
work copies. After the driver returns, it reconciles the snapshots
back to the real lists under the lock.
Add netif_rx_mode_sync() to opportunistically execute the pending
workqueue update inline, so that rx mode changes are committed
before returning to userspace:
- dev_change_flags (SIOCSIFFLAGS / RTM_NEWLINK)
- dev_set_promiscuity
- dev_set_allmulti
- dev_ifsioc SIOCADDMULTI / SIOCDELMULTI
- do_setlink (RTM_SETLINK)
Note that some deep hierarchies still do skip the lower updates via:
- dev_uc_sync
- dev_mc_sync
If we do end up hitting user-visible issues, we can add more calls to
netif_rx_mode_sync in specific places. But hopefully we should not,
the actual user-visible lists are still synced, it's that just HW state
that might be lagging.
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20260416185712.2155425-3-sdf@fomichev.me
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Introduce __hw_addr_list_snapshot() and __hw_addr_list_reconcile()
for use by the upcoming ndo_set_rx_mode_async callback.
The async rx_mode path needs to snapshot the device's unicast and
multicast address lists under the addr_lock, hand those snapshots
to the driver (which may sleep), and then propagate any sync_cnt
changes back to the real lists. Two identical snapshots are taken:
a work copy for the driver to pass to __hw_addr_sync_dev() and a
reference copy to compute deltas against.
__hw_addr_list_reconcile() walks the reference snapshot comparing
each entry against the work snapshot to determine what the driver
synced or unsynced. It then applies those deltas to the real list,
handling concurrent modifications:
- If the real entry was concurrently removed but the driver synced
it to hardware (delta > 0), re-insert a stale entry so the next
work run properly unsyncs it from hardware.
- If the entry still exists, apply the delta normally. An entry
whose refcount drops to zero is removed.
# dev_addr_test_snapshot_benchmark: 1024 addrs x 1000 snapshots: 89872802 ns total, 89872 ns/iter
# dev_addr_test_snapshot_benchmark.speed: slow
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20260416185712.2155425-2-sdf@fomichev.me
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
RFC 2516 Section 7 states that Protocol Field Compression (PFC) is NOT
RECOMMENDED for PPPoE. In practice, pppd does not support negotiating
PFC for PPPoE sessions, and the flow dissector driver has assumed an
uncompressed frame until the blamed commit.
During the review process of that commit [1], support for PFC is
suggested. However, having a compressed (1-byte) protocol field means
the subsequent PPP payload is shifted by one byte, causing 4-byte
misalignment for the network header and an unaligned access exception
on some architectures.
The exception can be reproduced by sending a PPPoE PFC frame to an
ethernet interface of a MIPS board, with RPS enabled, even if no PPPoE
session is active on that interface:
$ 0 : 00000000 80c40000 00000000 85144817
$ 4 : 00000008 00000100 80a75758 81dc9bb8
$ 8 : 00000010 8087ae2c 0000003d 00000000
$12 : 000000e0 00000039 00000000 00000000
$16 : 85043240 80a75758 81dc9bb8 00006488
$20 : 0000002f 00000007 85144810 80a70000
$24 : 81d1bda0 00000000
$28 : 81dc8000 81dc9aa8 00000000 805ead08
Hi : 00009d51
Lo : 2163358a
epc : 805e91f0 __skb_flow_dissect+0x1b0/0x1b50
ra : 805ead08 __skb_get_hash_net+0x74/0x12c
Status: 11000403 KERNEL EXL IE
Cause : 40800010 (ExcCode 04)
BadVA : 85144817
PrId : 0001992f (MIPS 1004Kc)
Call Trace:
[<805e91f0>] __skb_flow_dissect+0x1b0/0x1b50
[<805ead08>] __skb_get_hash_net+0x74/0x12c
[<805ef330>] get_rps_cpu+0x1b8/0x3fc
[<805fca70>] netif_receive_skb_list_internal+0x324/0x364
[<805fd120>] napi_complete_done+0x68/0x2a4
[<8058de5c>] mtk_napi_rx+0x228/0xfec
[<805fd398>] __napi_poll+0x3c/0x1c4
[<805fd754>] napi_threaded_poll_loop+0x234/0x29c
[<805fd848>] napi_threaded_poll+0x8c/0xb0
[<80053544>] kthread+0x104/0x12c
[<80002bd8>] ret_from_kernel_thread+0x14/0x1c
Code: 02d51821 1060045b 00000000 <8c640000> 3084000f 2c820005 144001a2 00042080 8e220000
To reduce the attack surface and maintain performance, do not process
PPPoE PFC frames.
[1] https://lore.kernel.org/r/20220630231016.GA392@debian.home
Fixes: 46126db9c8 ("flow_dissector: Add PPPoE dissectors")
Signed-off-by: Qingfang Deng <qingfang.deng@linux.dev>
Link: https://patch.msgid.link/20260415022456.141758-1-qingfang.deng@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Kyle Zeng