After SRv6 encapsulation the kernel looks up the route for the first SID,
that is the outer IPv6 destination of the encapsulated packet. This
post-encap SID route lookup uses the FIB table of the current routing
context. When the encap route is installed in a VRF, the VRF's table may
not have a route matching the SID. In that case another table should
handle it, e.g. one configured for underlay connectivity.
Add an optional SEG6_IPTUNNEL_TABLE attribute that selects the FIB table
used for this lookup. When set by the user, the attribute is honored on
both the input path (forwarded traffic) and the output path (locally
originated traffic). SRv6 encap routes that do not set the attribute use
the current routing context, as before.
For example:
# SID route installed in the underlay table 500
ip -6 route add fc00::100/128 via fd00::1 dev veth0 table 500
# encap route in vrf-100; the first SID is looked up in table 500
ip -6 route add cafe::1/128 vrf vrf-100 \
encap seg6 mode encap segs fc00::100 lookup 500 dev veth0
# or look up the SID in the main table
ip -6 route add cafe::1/128 vrf vrf-100 \
encap seg6 mode encap segs fc00::100 lookup main dev veth0
Suggested-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260711162907.6521-2-andrea.mayer@uniroma2.it
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Alice Mikityanska says:
====================
BIG TCP for UDP tunnels
This series is a follow-up to "BIG TCP without HBH in IPv6", and it adds
support for BIG TCP IPv4/IPv6 workloads in vxlan and geneve. Now that
IPv6 BIG TCP doesn't require stripping the HBH in all various
combinations in tunneled traffic, adding BIG TCP becomes feasible.
Patch 01 adds accessors for the length field in the UDP header, as
suggested by Paolo in review. The usage of udp_set_len is then added in
the following patches that start using length=0 in BIG TCP UDP packets.
Patches 02-04 close the gaps that prevent BIG TCP packets from going
through UDP tunnel code.
Patch 05 validates packets in udp_gro_receive to exclude packets with
length=0 from GRO aggregation.
Patch 06 is for proper formatting in tcpdump (set UDP len to 0 rather
than a trimmed value on overflow).
Patches 07-08 bump up tso_max_size for VXLAN and GENEVE.
Patch 09 adds selftests.
====================$
Link: https://patch.msgid.link/20260710134242.216538-1-alice.kernel@fastmail.im
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
skb->len may be bigger than 65535 in UDP-based tunnels that have BIG TCP
enabled. If GSO aggregates packets that large, set the length in the UDP
header to 0, so that tcpdump can print such packets properly (treating
them as RFC 2675 jumbograms). Later in the pipeline, __udp_gso_segment
will set uh->len to the size of individual packets.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260710134242.216538-7-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
In the previous commit we started using uh->len = 0 as a marker of a GRO
packet bigger than 65536 bytes. Filter out malformed packets coming from
the wire with len=0 at udp_gro_receive to exclude them from GRO.
Note that a similar check was present in udp_gro_receive_segment, but
not in the UDP socket gro_receive flow. By adding an early check to
udp_gro_receive, the check in udp_gro_receive_segment can be dropped.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260710134242.216538-6-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Currently, gro_max_size and gro_ipv4_max_size can be set to values
bigger than 65536, and GRO will happily aggregate UDP to the configured
size (for example, with TCP traffic in VXLAN tunnels). However,
udp_gro_complete uses the 16-bit length field in the UDP header to store
the length of the aggregated packet. It leads to the packet truncation
later in udp_rcv.
Fix this by storing 0 to the UDP length field and by restoring the real
length from skb->len in udp_rcv. IP GRO already can store 0 to the IP
length field, and iph_totlen()/ipv6_payload_len() are capable of
restoring the real length, because the relevant packets (BIG TCP
tunneled in UDP tunnels) will have skb_is_gso_tcp == true.
Additionally, restrict handling uh->len=0 in udpv6_rcv to BIG TCP and
jumbograms only by using the udp_get_len helper.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260710134242.216538-5-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Wherever a GSO packet can occur, and its length is used to fill the UDP
header, use udp_set_len that assigns 0 if the length doesn't fit 16
bits, so that the packet can be properly parsed and segmented later,
instead of having truncated length.
Use udp_get_len in udp_validate_len to treat BIG TCP packets as valid.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260710134242.216538-4-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
skb_segment is called for partial GSO, when netif_needs_gso returns true
in validate_xmit_skb. Partial GSO is needed, for example, when
segmentation of tunneled traffic is offloaded to a NIC that only
supports inner checksum offload.
Currently, skb_segment clamps the segment length to 65534 bytes, because
gso_size == 65535 is a special value GSO_BY_FRAGS, and we don't want
to accidentally assign mss = 65535, as it would fall into the
GSO_BY_FRAGS check further in the function.
This implementation, however, artificially blocks len > 65534, which is
possible since the introduction of BIG TCP. To allow bigger lengths and
avoid resegmentation of BIG TCP packets, store the gso_by_frags flag in
the beginning and don't use a special value of mss for this purpose
after mss was modified.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260710134242.216538-3-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Since BIG TCP for UDP tunnels will start using len=0 in the UDP header
as an indicator of a GSO packet bigger than 65535 bytes, this commit
introduces the following getter and setters to use tree-wide, in order
to explicitly mark places where len=0 may be expected, and handle them
properly:
1. udp_set_len() sets uh->len to its real value if it's not bigger than
65535, and to 0 otherwise: to be used in GSO context with aggregated
packets.
2. udp_set_len_short() is to be used when the length is known to fit 16
bits. It WARNs when the caller tries to assign a bigger value if
CONFIG_DEBUG_NET=y.
3. udp_get_len_short() returns len in host byte order: to be used on the
RX side to deal with non-aggregated packets, or to access the raw value
of the len field.
4. udp_get_len() decodes uh->len set by udp_set_len(). It checks whether
the packet is GSO to guard from malformed packets.
At the moment udp_set_len() is not used, a following commit will start
using it after enabling len>65535 for GSO.
Raw uh->len (in network byte order) is still accessed in a few places
for checksum calculation purposes, and to decode len=0 in udpv6_rcv for
jumbograms. udp_rcv and udpv6_rcv will be addressed by the commit that
starts using udp_set_len() to set UDP len=0 for BIG TCP packets in UDP
tunnels.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://patch.msgid.link/20260710134242.216538-2-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
To prevent RCU readers from accessing a partially destroyed in_device,
clear dev->ip_ptr early in inetdev_destroy() before freeing the
multicast list and individual IP addresses. This aligns the IPv4 teardown
sequence with the IPv6 implementation.
Cc: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Yuyang Huang <yuyanghuang@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260711005405.2861680-4-yuyanghuang@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
During address teardown, the netdevice's ip_ptr might be cleared before
the inetaddr notifier is called. In this case, __in_dev_get_rtnl()
returns NULL, causing the notifier to abort early and fail to update
the ARP filter.
Fix this by using the in_device pointer from the event argument
(ifa->ifa_dev) which is guaranteed to be valid.
Cc: Ido Schimmel <idosch@nvidia.com>
Cc: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Yuyang Huang <yuyanghuang@google.com>
Link: https://patch.msgid.link/20260711005405.2861680-3-yuyanghuang@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The tcp_syn_ack_timeout() function gets inlined by Clang,
preventing tracing. Since the call is not in the fast
path, prevent it from being inlined.
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260708180837.9507-1-emil@etsalapatis.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
After the previous patch, __br_multicast_send_query() no longer relies
on br_multicast_alloc_query() to determine the IGMP type of the query.
Remove the argument.
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260708122820.1298718-3-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Connecting two bridges on the same system [1] can result in a lockdep
splat [2].
The report is a false positive. Multicast queries are built and
transmitted under the bridge multicast lock. When the outgoing port of
one bridge is configured on top of another bridge, the transmit path
re-enters bridge code and acquires the other bridge's multicast lock in
order to snoop the query. Both lock instances share a single lockdep
class, so lockdep flags the nested acquisition as an AA deadlock.
Giving each bridge its own lock class will not solve the problem: the
reverse topology would produce an ABBA splat with the same pair of
classes. It also consumes a lockdep key per bridge.
Instead, fix the problem by deferring the transmission of the queries to
a workqueue. Build the skb and update querier state under the lock as
before, then enqueue the skb on a per multicast context queue and
schedule the work.
Purge the queue when the multicast context is de-initialized. At this
stage the work cannot be requeued. There is no need to take a reference
on skb->dev since the work cannot outlive the bridge or the bridge port.
Use the high priority workqueue to reduce the delay between the enqueue
time and the transmission time. With default settings (i.e., querier
interval - 255 seconds, query interval - 125 seconds) the extra delay
should not be a problem.
Avoid the unlikely case of the queue growing endlessly by limiting it to
1,000 skbs. Use this number for the simple reason that this is the
default Tx queue length.
Use local_bh_{disable,enable}() to disable/enable softIRQs and migration
in order to avoid corrupting the multicast statistics (per-CPU
u64_stats).
[1]
ip link add name br1 up type bridge mcast_snooping 1 mcast_querier 1
ip link add name br0 up type bridge mcast_snooping 1 mcast_querier 1
ip link add link br0 name br0.10 up master br1 type vlan id 10
[2]
WARNING: possible recursive locking detected
7.0.0-virtme-gb50c64a58a90 #1 Not tainted
[...]
ip/339 is trying to acquire lock:
ffff888104f0b480 (&br->multicast_lock){+.-.}-{3:3}, at: br_ip6_multicast_query (net/bridge/br_multicast.c:3584)
but task is already holding lock:
ffff888104f03480 (&br->multicast_lock){+.-.}-{3:3}, at: br_multicast_port_query_expired (net/bridge/br_multicast.c:1904)
[...]
Call Trace:
[...]
br_ip6_multicast_query (net/bridge/br_multicast.c:3584)
br_multicast_ipv6_rcv (net/bridge/br_multicast.c:3988)
br_dev_xmit (net/bridge/br_device.c:98 (discriminator 1))
dev_hard_start_xmit (net/core/dev.c:3904)
__dev_queue_xmit (net/core/dev.c:4871)
vlan_dev_hard_start_xmit (net/8021q/vlan_dev.c:131 (discriminator 1))
dev_hard_start_xmit (net/core/dev.c:3904)
__dev_queue_xmit (net/core/dev.c:4871)
br_dev_queue_push_xmit (net/bridge/br_forward.c:60)
__br_multicast_send_query (net/bridge/br_multicast.c:1811 (discriminator 1))
br_multicast_send_query (net/bridge/br_multicast.c:1889)
br_multicast_port_query_expired (net/bridge/br_multicast.c:1914)
call_timer_fn (kernel/time/timer.c:1749)
[...]
Reported-by: syzbot+d7b7f1412c02134efa6d@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/000000000000c4c9d405f2643e01@google.com/
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260708122820.1298718-2-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Pass source address, DSCP and output interface from the tunnel
configuration to ip_route_output() in ipip_fill_forward_path(), aligning
the route lookup with the slow path in ipip_tunnel_xmit().
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260708-ipip-route-lookup-fill_forward_path-v1-1-b77df74822ed@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
rt_flush_dev() can replace rt->dst.dev with blackhole_netdev while RCU
readers are running. ip_rt_send_redirect() and ip_rt_get_source() both
read rt->dst.dev more than once and use the results in one operation.
If rt->dst.dev changes between those reads, the operation can use values
from two devices. For example, ip_rt_send_redirect() can use in_dev from
the old device and the L3 master ifindex from blackhole_netdev.
Read rt->dst.dev once in these two functions and use the snapshot for the
later device accesses.
Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260708060537.17188-3-xuanqiang.luo@linux.dev
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
rt_flush_dev() replaces rt->dst.dev with blackhole_netdev on uncached
routes. The field is also exposed as dst.dev_rcu, and existing readers
use dst_dev_rcu().
Use rcu_assign_pointer() for the replacement, as dst_dev_put() already
does for the same field.
Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260708060537.17188-2-xuanqiang.luo@linux.dev
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Commit 98d0912e9f ("net: skbuff: fix missing zerocopy reference in
pskb_carve helpers") introduced two calls of net_zcopy_get(skb_zcopy(skb)).
In fact, skb_zcopy() has already been executed once before. When calling
net_zcopy_get(), skb_zcopy() always returns skb_uarg(skb), which results
in adding some unnecessary instructions in skb_zcopy. So, change these
two calls to directly use skb_uarg(skb) instead of skb_zcopy.
In addition, also use net_zcopy_get() instead of refcount_inc() in
pskb_expand_head() for code consistency.
No functional change intended.
Signed-off-by: Yun Lu <luyun@kylinos.cn>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260708055454.9167-1-luyun_611@163.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When a UDP encapsulation socket (e.g., FOU) receives a multicast
packet, __udp4_lib_mcast_deliver() and __udp6_lib_mcast_deliver()
call consume_skb() when udp_queue_rcv_skb() returns a positive value.
A positive return value from udp_queue_rcv_skb() indicates that the
encap_rcv handler (e.g., fou_udp_recv) has consumed the UDP header
and wants the packet to be resubmitted to the IP protocol handler
for further processing (e.g., as a GRE packet).
The unicast paths handle this correctly by propagating the return
value up to ip_protocol_deliver_rcu() / ip6_protocol_deliver_rcu()
for resubmission. However, the multicast paths destroy the packet
via consume_skb() instead of resubmitting it, causing silent packet
loss.
This affects any UDP encapsulation (FOU, GUE) combined with multicast
destination addresses.
Fix this by returning the value from udp_queue_rcv_skb() when it is
positive, matching the behavior of the corresponding unicast paths.
Note the sign difference between IPv4 and IPv6:
- IPv4: udp_unicast_rcv_skb() returns -ret, and
ip_protocol_deliver_rcu() resubmits when ret < 0
(using -ret as the protocol number).
- IPv6: udp6_unicast_rcv_skb() returns ret, and
ip6_protocol_deliver_rcu() resubmits when ret > 0
(using ret as the nexthdr).
Both mcast paths now follow the same convention as their respective
unicast paths.
Suggested-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Anton Danilov <littlesmilingcloud@gmail.com>
Assisted-by: Claude:claude-opus-4-6
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/5372ccac062193147e02b991d5328a5c3fa3a85a.1783372173.git.littlesmilingcloud@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
On CONFIG_INET=n builds, mpls_valid_fib_dump_req() walks the parsed
attribute table itself instead of calling ip_valid_fib_dump_req(). The
RTA_OIF arm passes tb[RTA_OIF] to nla_get_u32() without checking it is
present, so an RTM_GETROUTE dump for AF_MPLS with strict checking and no
RTA_OIF hits a NULL dereference.
RTM_GETROUTE is RTNL_KIND_GET, which rtnetlink_rcv_msg() permits without
CAP_NET_ADMIN, so an unprivileged user can trigger it.
Oops: general protection fault, probably for non-canonical address
0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:mpls_valid_fib_dump_req (net/mpls/af_mpls.c:2189)
Call Trace:
mpls_dump_routes (net/mpls/af_mpls.c:2236)
netlink_dump (net/netlink/af_netlink.c:2331)
__netlink_dump_start (net/netlink/af_netlink.c:2446)
rtnetlink_rcv_msg (net/core/rtnetlink.c:7033)
netlink_rcv_skb (net/netlink/af_netlink.c:2556)
netlink_unicast (net/netlink/af_netlink.c:1345)
netlink_sendmsg (net/netlink/af_netlink.c:1900)
__sock_sendmsg (net/socket.c:790)
____sys_sendmsg (net/socket.c:2684)
___sys_sendmsg (net/socket.c:2738)
__sys_sendmsg (net/socket.c:2770)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
Skip unset attributes, as ip_valid_fib_dump_req() does.
Fixes: 196cfebf89 ("net/mpls: Handle kernel side filtering of route dumps")
Assisted-by: Claude:claude-opus-4-8
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260711114958.1009619-3-bestswngs@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
llc_sap_add_socket() takes a SAP reference for each socket added to a SAP,
and llc_sap_remove_socket() releases it. llc_create_incoming_sock() takes
an additional SAP reference after adding the child socket.
This extra reference was balanced by an explicit llc_sap_put() in
llc_ui_release() until commit 3100aa9d74 ("llc: fix SAP reference
counting w.r.t. socket handling") removed that put. The corresponding hold
in the accept path was left behind.
When such a child socket is removed, only the reference taken by
llc_sap_add_socket() is released. The extra reference keeps the SAP alive
after its last socket is removed. Remove the obsolete hold.
Fixes: 3100aa9d74 ("llc: fix SAP reference counting w.r.t. socket handling")
Cc: stable@vger.kernel.org
Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Link: https://patch.msgid.link/20260712130343.518797-1-xuanqiang.luo@linux.dev
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
skb_pool_flush() has no callers left in net/core/netpoll.c after
netconsole took over the pool lifecycle. Inline its body into
netconsole_skb_pool_flush() (the only caller) and drop the function
and its export from netpoll. The prototype goes from
<linux/netpoll.h>.
Pure code motion: cancel_work_sync() + skb_queue_purge_reason()
semantics are unchanged.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-6-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
refill_skbs() is now only called from netconsole (directly via
netconsole_skb_pool_init() and indirectly via the just-moved
refill_skbs_work_handler()), and the MAX_UDP_CHUNK / MAX_SKBS /
MAX_SKB_SIZE macros are private to it. Move them all into
drivers/net/netconsole.c.
MAX_UDP_CHUNK and MAX_SKB_SIZE were promoted to <linux/netpoll.h>
by commit 6c537b845c ("netconsole: do not dequeue pooled skbs that
cannot satisfy len") so find_skb() could detect oversized requests
against the same value refill_skbs() used. With both functions now
local to netconsole, the shared definition no longer needs to live
in the header.
Pure code motion: bodies and pool sizing semantics are unchanged.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-5-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The work handler is wired via INIT_WORK() in
netconsole_skb_pool_init() and has no other callers since the
previous patch took the skb pool lifecycle out of __netpoll_setup().
Move the function body into drivers/net/netconsole.c as a
file-static helper, drop EXPORT_SYMBOL_GPL() and remove the
prototype from <linux/netpoll.h>.
Pure code motion: the body is unchanged and still calls the
exported refill_skbs() in net/core/netpoll.c.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-4-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The fallback skb pool fronted by find_skb() is netconsole's only client:
every other netpoll goes through __netpoll_setup() / netpoll_send_skb()
without ever touching np->skb_pool.
Today __netpoll_setup() and __netpoll_cleanup() create and destroy the
pool for everyone, paying ~48 KB of pre-allocated skbs per netpoll
instance that only netconsole uses, what a waste!
Move the responsibility to netconsole. __netpoll_setup() did this under
the RTNL, but netconsole enables targets from enabled_store() /
alloc_param_target() without it, while the teardown path flushes the pool
(cancel_work_sync() + skb_queue_purge()) under the RTNL from
netconsole_process_cleanups_core(). Initialising the queue head and the
refill work on every enable would therefore race that flush.
They only need initialising once: after a flush the queue head is left
valid and empty and cancel_work_sync() leaves the work re-armable. Set
them up in alloc_and_init(), while the target is not yet reachable, and
let the enable paths only refill the pool via refill_skbs(), which
serialises with the flush through skb_pool.lock. See discussions in [1]
Link: https://lore.kernel.org/all/alDMvD5S7TZnoD_V@gmail.com/ [1]
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-3-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
These three helpers manage the per-netpoll fallback skb pool. They
are file-static today because all of their callers live in
net/core/netpoll.c. Subsequent patches relocate the pool's owner
from struct netpoll to the only consumer that actually uses it
(netconsole), and that work needs netconsole to drive the helpers
directly while the function bodies still live here.
Drop static, add prototypes in <linux/netpoll.h>, and
EXPORT_SYMBOL_GPL() each. No behaviour change.
The exports are transitional. Each helper is moved into
drivers/net/netconsole.c later in this series, and at that point
its EXPORT_SYMBOL_GPL() and prototype are dropped. By the end of
the series no symbol introduced here remains exported.
The goal of this patch is to make the subsequente patches easy to
review.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-2-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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: 659a2899a5 ("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>
-----BEGIN PGP SIGNATURE-----
iIkEABYKADEWIQSl+MghEFFAdY3pYJLMOmT6rpmt0gUCaljFDxMcbWtsQHBlbmd1
dHJvbml4LmRlAAoJEMw6ZPquma3ScvEBAMN4/7N+Es+yBfeHYu2A+6b+5qeW+4Px
WtxSffc9OxxtAP9H/UhgxnZdzgCalXipwZGjwSKgm87vPU8H1GDKlX3LBw==
=EJTl
-----END PGP SIGNATURE-----
Merge tag 'linux-can-fixes-for-7.2-20260716' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can
Marc Kleine-Budde says:
====================
pull-request: can 2026-07-16
this is a pull request of 19 patches for net/main.
The first patch is by Alexander Hölzl and fixes the Kconfig
description of the vxcan driver.
Next patch by Fan Wu fixes the tear down order in the esd_usb driver.
Followed by a patch by Oliver Hartkopp that adds missing locking for
the raw flags in the CAN_RAW protocol.
Shuhao Fu's patch for the j1939 protocol fix lockless
local-destination check.
Stéphane Grosjean updates their email address.
The next 11 patches all target the CAM Broadcast Manager protocol. One
contributed by Lee Jones the remaining ones by Oliver Hartkopp. They
fix several concurrency and locking issues found by various bots.
The last 3 patches are also by Oliver Hartkopp fixing concurrency and
locking issues found by various bots in the CAN ISO Transport
Protocol.
linux-can-fixes-for-7.2-20260716
* tag 'linux-can-fixes-for-7.2-20260716' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can:
can: isotp: serialize TX state transitions under so->rx_lock
can: isotp: fix use-after-free race with concurrent NETDEV_UNREGISTER
can: isotp: use unconditional synchronize_rcu() in isotp_release()
can: bcm: track a single source interface for ANYDEV timeout/throttle ops
can: bcm: fix data race on rx_stamp/rx_ifindex in bcm_rx_handler()
can: bcm: fix stale rx/tx ops after device removal
can: bcm: add missing device refcount for CAN filter removal
can: bcm: validate frame length in bcm_rx_setup() for RTR replies
can: bcm: extend bcm_tx_lock usage for data and timer updates
can: bcm: add missing rcu list annotations and operations
can: bcm: fix CAN frame rx/tx statistics
can: bcm: add locking when updating filter and timer values
can: bcm: fix lockless bound/ifindex race and silent RX_SETUP failure
can: bcm: defer rx_op deallocation to workqueue to fix thrtimer UAF
can: peak: Modification of references to email accounts being deleted
can: j1939: fix lockless local-destination check
can: raw: add locking for raw flags bitfield
can: esd_usb: kill anchored URBs before freeing netdevs
can: vxcan: Kconfig: fix description stating no local echo provided
====================
Link: https://patch.msgid.link/20260716155528.809908-1-mkl@pengutronix.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
-----BEGIN PGP SIGNATURE-----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=eXsP
-----END PGP SIGNATURE-----
Merge tag 'nf-26-07-10' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Florian Westphal says:
====================
netfilter: updates for net
The following patchset contains Netfilter fixes for *net*.
These are fixes for bugs except patches 6 and 9 which fix issues added in
last PR and 7.1-rc1.
1) Reject unsupported target families in xt_nat_checkentry().
From Wyatt Feng.
2) Fix inverted time_after() check in ecache_work_evict_list().
Causes pointless work rescheds and thus way longer time to
clear the pending event backlog. From Yizhou Zhao.
3) Fix a use-after-free in br_ip6_fragment() caused by a dangling prevhdr
pointer. From Xiang Mei.
4) Fix incorrect conntrack zone comparison in nf_conncount tuple
deduplication. Pass IP_CT_DIR_ORIGINAL, not zone direction.
From Yizhou Zhao.
5) Add bridge tunnel flowtable regression test for a bug that
got fixed in the previous PR. From Zhengyang Chen.
6) Use the correct direction when setting up tunnel routes in the flowtable
xmit path. From Pablo Neira Ayuso. This fixes a bug added in the
previous PR.
7) Reload IP header after potential skb head reallocation in IPVS.
8) Fix incorrect IPv6 transport offsets in TCP application code. Correct the
ICMPv6 header offset to ensure proper checksumming with extension headers,
from Julian Anastasov. this is a followup to the previous PR.
9) Remove null-termination requirement for xt_physdev masks, this broke
device names with 15 characters.
netfilter pull request nf-26-07-10
* tag 'nf-26-07-10' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: xt_physdev: masks are not c-strings
ipvs: fix more places with wrong ipv6 transport offsets
ipvs: reload ip header after head reallocation
netfilter: flowtable: use correct direction to set up tunnel route
selftests: netfilter: add bridge tunnel flowtable regression
netfilter: nf_conncount: fix zone comparison in tuple dedup
netfilter: bridge: fix stale prevhdr pointer in br_ip6_fragment()
netfilter: ecache: fix inverted time_after() check
netfilter: xt_nat: reject unsupported target families
====================
Link: https://patch.msgid.link/20260710143733.29741-1-fw@strlen.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The TX state machine (so->tx.state) is driven from three contexts:
sendmsg() claiming and progressing a transfer, the RX path consuming
Flow Control/echo frames, and two hrtimers timing out a stalled
transfer. Mixing a lock-free cmpxchg() claim in sendmsg() with
hrtimer_cancel() calls made under so->rx_lock elsewhere left windows
where a frame or timer callback could act on a state that had already
moved on, corrupting an unrelated transfer.
so->rx_lock now covers the full lifecycle of a TX claim: sendmsg()
takes it to check so->tx.state is ISOTP_IDLE, switch it to
ISOTP_SENDING, bump so->tx_gen and drain the previous transfer's
timers - all as one critical section. isotp_rcv_fc()/isotp_rcv_cf()
already run under this lock via isotp_rcv(), and isotp_rcv_echo() now
takes it itself, so none of them can ever observe a transfer mid-claim.
This also means a transfer can no longer be handed to sendmsg()'s
cleanup paths (signal or send error) while another thread is
concurrently claiming or finishing it, so those paths can cancel
timers and reset the state unconditionally.
isotp_release() claims the socket the same way, so a racing sendmsg()
sees a consistent ISOTP_SHUTDOWN and skips arming its timer or sending.
Only the hrtimer callbacks stay outside so->rx_lock, since they run
under so->rx_lock's cancellation elsewhere and taking it themselves
would deadlock. so->tx_gen lets them recognize whether the transfer
they timed out is still the one currently active, so they don't
report an error against a transfer that has since completed or been
superseded.
Fixes: e057dd3fc2 ("can: add ISO 15765-2:2016 transport protocol")
Reported-by: sashiko-bot@kernel.org
Closes: https://lore.kernel.org/linux-can/20260710142146.BDAE61F000E9@smtp.kernel.org/
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260712-isotp-fixes-v10-3-793a1b1ce17f@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
isotp_release() looked up the bound network device via dev_get_by_index()
using the stored ifindex. During device unregistration the device is
unlisted from the ifindex hash before the NETDEV_UNREGISTER notifier
chain runs, so a concurrent isotp_release() could find no device, skip
can_rx_unregister() entirely, and still proceed to free the socket.
Since isotp_release() had already removed itself from the isotp
notifier list at that point, isotp_notify() would never get a chance to
clean up either, leaving a stale CAN filter that keeps pointing at the
freed socket.
Fix this the same way raw.c already does: hold a tracked reference to
the bound net_device in the socket (so->dev/so->dev_tracker) from
bind() onward instead of re-resolving it from the ifindex, and
serialize bind()/release() with rtnl_lock() so that so->dev is always
consistent with what the NETDEV_UNREGISTER notifier sees. so->dev
stays valid regardless of ifindex-hash unlisting, and is only ever
cleared by whichever of isotp_release()/isotp_notify() gets there
first, so the filter is always removed exactly once.
isotp_bind() now rejects a (re)bind with -EAGAIN while so->[tx|rx].state
isn't ISOTP_IDLE yet, so a timer left running by a prior
NETDEV_UNREGISTER can't act on a newly bound so->ifindex. Both checks
share the same lock_sock() section, so there is no window in which a
concurrent isotp_notify() clearing so->bound could be missed.
Fixes: e057dd3fc2 ("can: add ISO 15765-2:2016 transport protocol")
Reported-by: sashiko-bot@kernel.org
Closes: https://lore.kernel.org/linux-can/20260707101420.47F261F000E9@smtp.kernel.org/
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260712-isotp-fixes-v10-2-793a1b1ce17f@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
isotp_notify() unregisters the (RCU) CAN filters via can_rx_unregister()
and clears so->bound without waiting for a grace period. isotp_release()
uses so->bound to decide whether it needs to call synchronize_rcu()
before cancelling so->rxtimer, so when NETDEV_UNREGISTER runs first it
skips that synchronize_rcu() and can cancel the timer while an
in-flight isotp_rcv() is still executing and about to re-arm it via
isotp_send_fc(), leading to a use-after-free timer callback on the
freed socket.
sakisho-bot remarked a problem with rtnl_lock held in isotp_notify(),
therefore make isotp_release() always call synchronize_rcu() before
cancelling the timers, regardless of so->bound. This still closes the
original race (isotp_notify() clearing so->bound without waiting for
in-flight isotp_rcv() callers before isotp_release() cancels the RX
timer) without adding any RCU wait to the netdevice notifier path.
Fixes: 14a4696bc3 ("can: isotp: isotp_release(): omit unintended hrtimer restart on socket release")
Closes: https://lore.kernel.org/linux-can/20260707085210.6B6C01F000E9@smtp.kernel.org/
Reported-by: Nico Yip <zdi-disclosures@trendmicro.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260712-isotp-fixes-v10-1-793a1b1ce17f@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
An ANYDEV rx op (ifindex == 0) with an active RX timeout and/or
throttle timer has no defined semantics when matching frames arrive
from several interfaces: bcm_rx_handler() can run concurrently for
the same op on different CPUs, racing hrtimer_cancel()/
bcm_rx_starttimer() against bcm_rx_timeout_handler() and causing
spurious RX_TIMEOUT notifications and last_frames corruption. The
same concurrency lets throttled multiplex frames from different
interfaces clobber the single rx_ifindex/rx_stamp fields shared by
the op.
Add op->if_detected to track the first interface that delivers a
matching frame while a timeout/throttle timer is configured, and
reject frames from any other interface for that op. The claim is
decided in bcm_rx_handler() before hrtimer_cancel() touches
op->timer, so a rejected frame can never disturb the claimed
interface's watchdog. RTR-mode ops are excluded via RX_RTR_FRAME,
independent of kt_ival1/kt_ival2, since those may briefly hold a
stale value from an earlier non-RTR configuration.
The claim is released in bcm_notify() on NETDEV_UNREGISTER and in
bcm_rx_setup() when SETTIMER reconfigures the timer values.
A (re-)claim is only possible on CAN devices in NETREG_REGISTERED
dev->reg_state to cover the release in bcm_notify() where reg_state
becomes NETREG_UNREGISTERING until synchronize_net().
Fixes: ffd980f976 ("[CAN]: Add broadcast manager (bcm) protocol")
Reported-by: sashiko-bot@kernel.org
Closes: https://lore.kernel.org/linux-can/20260709105031.1A39C1F000E9@smtp.kernel.org/
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-11-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
For an rx op subscribed on all interfaces (ifindex == 0), the same op
is registered once in the shared per-netns wildcard filter list, so
bcm_rx_handler() can run concurrently on different CPUs for frames
arriving on different net devices.
op->rx_stamp and op->rx_ifindex were written before bcm_rx_update_lock was
taken, allowing concurrent writers to race each other - including a torn
store of the 64-bit rx_stamp on 32-bit platforms.
Beyond a torn store bcm_send_to_user() must report the timestamp/ifindex
of the very same frame whose content it is delivering. So the assignment
is placed in the same unbroken bcm_rx_update_lock section as the content
comparison.
As a side effect, the RTR-request frame feature (which never reach
bcm_send_to_user()) no longer updates rx_stamp/rx_ifindex, since only
the notification path needs them.
Fixes: ffd980f976 ("[CAN]: Add broadcast manager (bcm) protocol")
Reported-by: sashiko-bot@kernel.org
Closes: https://lore.kernel.org/linux-can/20260707145135.5BC831F00A3A@smtp.kernel.org/
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-10-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
RX: an RX_SETUP update(!) for an existing op skipped can_rx_register()
unconditionally, even when a concurrent NETDEV_UNREGISTER had already
torn down its registration (op->rx_reg_dev == NULL). This silently
did not re-enable frame delivery for that updated filter. bcm_rx_setup()
now re-registers in that case, while leaving rx_ops with ifindex = 0
(all CAN devices) which never carry a tracked rx_reg_dev registered as-is.
TX: bcm_notify() only handled bo->rx_ops on NETDEV_UNREGISTER, leaving
tx_ops with an active cyclic transmission re-arming its hrtimer
indefinitely to execute bcm_tx_timeout_handler(). Cancelling the hrtimer
prevents the runaway timer and any injection into a later reused ifindex,
since nothing else calls bcm_can_tx() for the op until an explicit
TX_SETUP update re-arms it.
Unlike bcm_rx_unreg(), which clears the tracked rx_reg_dev for rx_ops,
the ifindex is intentionally left unchanged for tx_ops. bcm_tx_setup()
always rejects ifindex 0, so clearing it would strand the op: neither a
later TX_SETUP (bcm_find_op()) nor TX_DELETE (bcm_delete_tx_op()) could
ever find it again, since both require an exact ifindex match.
Reported-by: sashiko-bot@kernel.org
Closes: https://lore.kernel.org/linux-can/20260708094536.DDF821F00A3A@smtp.kernel.org/
Closes: https://lore.kernel.org/linux-can/20260708154039.347ED1F000E9@smtp.kernel.org/
Fixes: ffd980f976 ("[CAN]: Add broadcast manager (bcm) protocol")
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-9-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
sashiko-bot remarked a problem with a concurrent device unregistration
in isotp.c which also is present in the bcm.c code. A former fix for raw.c
commit c275a176e4 ("can: raw: add missing refcount for memory leak fix")
introduced a netdevice_tracker which solves the issue for bcm.c too.
bcm_release(), bcm_delete_rx_op() and bcm_notifier() relied on
dev_get_by_index(ifindex) to re-find the device for an rx_op before
unregistering its filter. If a concurrent NETDEV_UNREGISTER has already
unlisted the device from the ifindex table, that lookup fails and
can_rx_unregister() is silently skipped, leaving a stale CAN filter
pointing at the soon-to-be-freed bcm_op/socket.
Hold a netdev_hold()/netdev_put() tracked reference on op->rx_reg_dev
from the moment the rx filter is registered in bcm_rx_setup() until it
is unregistered in bcm_rx_unreg(), and use that reference directly in
bcm_release() and bcm_delete_rx_op() instead of re-looking the device
up by ifindex.
Reported-by: sashiko-bot@kernel.org
Closes: https://sashiko.dev/#/patchset/20260707094716.63578-1-socketcan@hartkopp.net
Fixes: ffd980f976 ("[CAN]: Add broadcast manager (bcm) protocol")
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-8-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
bcm_tx_setup() validates cf->len against the CAN/CAN FD DLC limits
before installing frames for TX_SETUP, but bcm_rx_setup() never did
the same for the RTR-reply frame configured via RX_SETUP with
RX_RTR_FRAME.
Fixes: ffd980f976 ("[CAN]: Add broadcast manager (bcm) protocol")
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-7-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Stage new CAN frame content for an existing tx op into a kmalloc()'d
buffer and validate it there, mirroring the approach already used in
bcm_rx_setup(). Only copy the validated data into op->frames while
holding op->bcm_tx_lock, so bcm_can_tx() and bcm_tx_timeout_handler()
can no longer observe a partially updated or unvalidated frame.
Add a missing error path for memcpy_from_msg() when copying CAN frame
data from userspace.
Also move the kt_ival1/kt_ival2/ival1/ival2 updates in bcm_tx_setup()
under op->bcm_tx_lock, and read kt_ival1/kt_ival2/count under the same
lock in bcm_tx_set_expiry() and bcm_tx_timeout_handler(), closing the
torn 64-bit ktime_t read on 32-bit platforms.
Fixes: c2aba69d0c ("can: bcm: add locking for bcm_op runtime updates")
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-6-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
sashiko-bot remarked the missing use of list_add_rcu() in
bcm_[rx|tx]_setup() to have a proper initialized bcm_op structure
when bcm_proc_show() traverses the bcm_op's under rcu_read_lock().
To cover all initial settings of the bcm_op's the list_add_rcu() calls
are moved to the end of the setup code.
While at it, also fix the mirroring removal side: bcm_release() called
bcm_remove_op() - which frees the op via call_rcu() - on ops that were
still linked in bo->tx_ops/bo->rx_ops, without list_del_rcu() first.
Unlink each op with list_del_rcu() before handing it to bcm_remove_op(),
matching the existing pattern in bcm_delete_tx_op()/bcm_delete_rx_op().
Reported-by: sashiko-reviews@lists.linux.dev
Closes: https://lore.kernel.org/linux-can/20260610094654.A1FFE1F00893@smtp.kernel.org/
Fixes: dac5e62491 ("can: bcm: add missing rcu read protection for procfs content")
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-5-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
KCSAN detected a data race within the bcm_rx_handler() when two CAN frames
have been simultaneously received and processed in a single rx op by two
different CPUs.
Use atomic operations with (signed) long data types to access the
statistics in the hot path to fix the KCSAN complaint.
Additionally simplify the update and check of statistics overflow by
using the atomic operations in separate bcm_update_[rx|tx]_stats()
functions. The rx variant runs under bcm_rx_update_lock to prevent
races when resetting the two rx counters; the tx variant runs under
bcm_tx_lock and only needs to guard its own counter's overflow.
As the rx path resets its values already at LONG_MAX / 100, there is
no conflict between the two locking domains (bcm_rx_update_lock vs.
bcm_tx_lock) even for ops that use both paths.
The rx statistics update and the frames_filtered update in
bcm_rx_changed() were previously performed in two separate
bcm_rx_update_lock sections. For an rx op subscribed on all interfaces
(ifindex == 0), bcm_rx_handler() can run concurrently on different
CPUs, so a counter reset by one CPU between these two sections could
leave frames_filtered larger than frames_abs on another CPU, producing
a bogus (even negative) reduction percentage in procfs. Update the
statistics in the same critical section as bcm_rx_changed() to close
this gap, which also removes the now unneeded extra lock/unlock pair
around the traffic_flags calculation.
Fixes: ffd980f976 ("[CAN]: Add broadcast manager (bcm) protocol")
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-4-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
KCSAN detected a simultaneous access to timer values that can be
overwritten in bcm_rx_setup() when updating timer and filter content
while bcm_rx_handler(), bcm_rx_timeout_handler() or bcm_rx_thr_handler()
run concurrently on incoming CAN traffic.
Protect the timer (ival1/ival2/kt_ival1/kt_ival2/kt_lastmsg) and filter
(nframes/flags/frames/last_frames) updates in bcm_rx_setup() with a new
per-op bcm_rx_update_lock, taken with the matching scope in the RX
handlers. memcpy_from_msg() is staged into a temporary buffer before the
lock is taken, since it can sleep and must not run under a spinlock.
hrtimer_cancel() is always called without bcm_rx_update_lock held, since
bcm_rx_timeout_handler()/bcm_rx_thr_handler() take the same lock and a
running callback would otherwise deadlock against the canceller.
Also close a related race: bcm_rx_setup() cleared the RTR flag in the
stored reply frame's can_id as a separate, unprotected step after the
frame content was already installed, so a concurrent bcm_rx_handler()
could transmit a stale reply with CAN_RTR_FLAG still set. Fold that
normalization into the initial frame preparation instead (on the staged
buffer for updates, directly on op->frames pre-registration for new
ops), so the installed frame is always atomically self-consistent.
bcm_rx_handler()'s RX_RTR_FRAME check now takes a lock-protected
snapshot of op->flags before deciding whether to call bcm_can_tx(),
but does not hold the lock across that call.
Also take a lock-protected snapshot of the currframe in bcm_can_tx()
to avoid partly overwrites by content updates in bcm_tx_setup().
Finally check if a TX_RESET_MULTI_IDX/SETTIMER might have reset
op->currframe between the two locked sections in bcm_can_tx().
Omit calling hrtimer_forward() with zero interval in bcm_rx_thr_handler().
kt_ival2 may have been concurrently cleared by bcm_rx_setup() before it
cancels this timer, so check kt_ival2 inside the bcm_rx_update_lock.
Fixes: c2aba69d0c ("can: bcm: add locking for bcm_op runtime updates")
Reported-by: syzbot+75e5e4ae00c3b4bb544e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-can/6975d5cf.a00a0220.33ccc7.0022.GAE@google.com/
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-3-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
bcm_sendmsg() reads bo->ifindex and checks bo->bound before taking
lock_sock(), while bcm_notify(), bcm_connect() and bcm_release() all
mutate both fields under that same lock. Because the lockless reads
and the locked writes are unordered with respect to each other, a
racing bcm_notify() (device unregister) or bcm_connect() (concurrent
bind on another thread sharing the socket) can make bcm_sendmsg()
observe an inconsistent combination, e.g. a stale bound=1 together
with the now-cleared ifindex=0, silently turning a socket bound to a
specific CAN interface into one that also matches "any" interface.
Keep the lockless bo->bound check purely as a fast-path reject, and
move the ifindex read (and a bo->bound re-check) into the locked
section, where every writer already serializes. This removes the
possibility of observing the two fields torn against each other,
rather than trying to fix it with more READ_ONCE()/WRITE_ONCE() pairs
on two independently updated fields. Annotate the now-purely-lockless
bo->bound accesses consistently across all its write sites.
Also fix bcm_rx_setup() silently returning success when the target
device disappears concurrently instead of reporting -ENODEV, so a
broken RX op is no longer left registered as if it had succeeded.
Fixes: ffd980f976 ("[CAN]: Add broadcast manager (bcm) protocol")
Reported-by: Ginger <ginger.jzllee@gmail.com>
Closes: https://lore.kernel.org/linux-can/CAGp+u1aBK8QVjsvAxM2Ldzep4rEbsP9x_pV3At4g=h1kVEtyhA@mail.gmail.com/
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-2-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Commit f1b4e32aca ("can: bcm: use call_rcu() instead of costly
synchronize_rcu()") replaced synchronize_rcu() in bcm_delete_rx_op()
with call_rcu() and introduced the RX_NO_AUTOTIMER flag.
However, this flag check was omitted for thrtimer in the packet rx
fast-path. During BCM RX operation teardown, a concurrent RCU reader
(bcm_rx_handler) can race and re-arm thrtimer via
bcm_rx_update_and_send() after call_rcu() has been scheduled. Once
the RCU grace period elapses, bcm_op is freed. The subsequently
firing thrtimer then dereferences the deallocated op, causing a UAF.
Adding flag checks to the rx fast-path (bcm_rx_update_and_send) does not
fully close the TOCTOU race and introduces latency for every CAN frame.
Conversely, calling hrtimer_cancel() directly inside the RCU callback
(softirq context) is fatal as hrtimer_cancel() can sleep, triggering
a "scheduling while atomic" panic.
Resolve this by deferring the timer cancellation and memory free to a
dedicated unbound workqueue (bcm_wq). The RCU callback now queues a
work item to bcm_wq, which safely cancels both timers and deallocates
memory in sleepable process context. A dedicated workqueue is used to
prevent system-wide WQ saturation and is cleanly flushed/destroyed
on module unload to avoid rmmod page faults.
Since the deferred work can now outlive the calling context by an
unbounded amount, also take a reference on op->sk when it is assigned
and drop it only once the deferred work has cancelled both timers, so a
socket can no longer be freed out from under a still-armed timer whose
callback (bcm_send_to_user()) dereferences op->sk.
Fixes: f1b4e32aca ("can: bcm: use call_rcu() instead of costly synchronize_rcu()")
Tested-by: Feng Xue <feng.xue@outlook.com>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260714-bcm_fixes-v15-1-562f7e3e42da@hartkopp.net
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
j1939_priv.ents[].nusers is documented as protected by priv->lock, and
its updates already happen under that lock. j1939_can_recv() also reads
it under read_lock_bh(). However, j1939_session_skb_queue() and
j1939_tp_send() still read priv->ents[da].nusers without taking the
lock.
Those transport-side checks decide whether to set J1939_ECU_LOCAL_DST, so
they can race with j1939_local_ecu_get() and j1939_local_ecu_put() while
userspace is binding or releasing sockets concurrently with TP traffic.
This can misclassify TP/ETP sessions as local or remote and take the wrong
transport path.
Fix both transport paths by routing the destination-locality check through
a helper that reads ents[].nusers under read_lock_bh(&priv->lock).
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Signed-off-by: Shuhao Fu <sfual@cse.ust.hk>
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/20260419140614.GA4041240@chcpu16
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
With commit 890e5198a6 ("can: raw: use bitfields to store flags in
struct raw_sock") the formerly separate integer values have been integrated
into a single bitfield. This led to a read-modify-write operation when
changing a flag in raw_setsockopt() which now needs a locking to prevent
concurrent access.
Instead of adding a lock/unlock hell in each of the flag manipulations this
patch introduces a wrapper for a new raw_setsockopt_locked() function
analogue to the isotp_setsockopt[_locked]() approach in net/can/isotp.c
Fixes: 890e5198a6 ("can: raw: use bitfields to store flags in struct raw_sock")
Reported-by: Eulgyu Kim <eulgyukim@snu.ac.kr>
Closes: https://lore.kernel.org/linux-can/20260503112200.22727-1-eulgyukim@snu.ac.kr/
Tested-by: Eulgyu Kim <eulgyukim@snu.ac.kr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Reviewed-by: Vincent Mailhol <mailhol@kernel.org>
Tested-by: Vincent Mailhol <mailhol@kernel.org>
Link: https://patch.msgid.link/20260504111928.41856-1-socketcan@hartkopp.net
[mkl: use Closes tag instead of Link]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
MGMT_EV_DEVICE_DISCONNECTED carries a reason field which is defined to
be one of MGMT_DEV_DISCONN_* (0x00..0x05). hci_disconn_complete_evt()
converts the HCI error with hci_to_mgmt_reason(), but two other paths
pass the raw HCI error straight through:
hci_cs_disconnect() -> cp->reason
mgmt_connect_failed() -> status
The latter is reached whenever the adapter is powered off or suspended:
hci_disconnect_all_sync() aborts every link with
HCI_ERROR_REMOTE_POWER_OFF, hci_disconnect_sync() deliberately does not
wait for HCI_EV_DISCONN_COMPLETE for that reason, so that
hci_abort_conn_sync() finishes the connection off through
hci_conn_failed() instead.
As a result userspace sees an out of range reason:
@ MGMT Event: Device Disconnected (0x000c) plen 8
BR/EDR Address: 8C:A9:6F:2C:51:46
Reason: Reserved (0x15)
bluetoothd: btd_bearer_disconnected() Unknown disconnection value: 21
bluetoothd: device_disconnected() Unknown disconnection value: 21
Export hci_to_mgmt_reason() and use it in both places, so that a power
off is reported as MGMT_DEV_DISCONN_REMOTE rather than as the raw
HCI_ERROR_REMOTE_POWER_OFF (0x15).
Fixes: d47da6bd4c ("Bluetooth: hci_core: Fix sending MGMT_EV_CONNECT_FAILED")
Fixes: 182ee45da0 ("Bluetooth: hci_sync: Rework hci_suspend_notifier")
Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
hci_conn_params_lookup requires hdev->lock be held, otherwise the list
iteration or param access is not safe.
Hold hdev->lock for params lookups in hci_sync.
Fixes: c530569adc ("Bluetooth: hci_core: Introduce HCI_CONN_FLAG_PAST")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
