<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel.git/net/can/bcm.c, branch linux-6.18.y</title>
<subtitle>Hosts the 0x221E linux distro kernel.
</subtitle>
<id>https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-6.18.y</id>
<link rel='self' href='https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-6.18.y'/>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/'/>
<updated>2026-03-12T11:09:51Z</updated>
<entry>
<title>can: bcm: fix locking for bcm_op runtime updates</title>
<updated>2026-03-12T11:09:51Z</updated>
<author>
<name>Oliver Hartkopp</name>
</author>
<published>2026-02-18T10:58:06Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=8215ba7bc99e84e66fd6938874ec4330a9d96518'/>
<id>urn:sha1:8215ba7bc99e84e66fd6938874ec4330a9d96518</id>
<content type='text'>
[ Upstream commit c35636e91e392e1540949bbc67932167cb48bc3a ]

Commit c2aba69d0c36 ("can: bcm: add locking for bcm_op runtime updates")
added a locking for some variables that can be modified at runtime when
updating the sending bcm_op with a new TX_SETUP command in bcm_tx_setup().

Usually the RX_SETUP only handles and filters incoming traffic with one
exception: When the RX_RTR_FRAME flag is set a predefined CAN frame is
sent when a specific RTR frame is received. Therefore the rx bcm_op uses
bcm_can_tx() which uses the bcm_tx_lock that was only initialized in
bcm_tx_setup(). Add the missing spin_lock_init() when allocating the
bcm_op in bcm_rx_setup() to handle the RTR case properly.

Fixes: c2aba69d0c36 ("can: bcm: add locking for bcm_op runtime updates")
Reported-by: syzbot+5b11eccc403dd1cea9f8@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-can/699466e4.a70a0220.2c38d7.00ff.GAE@google.com/
Signed-off-by: Oliver Hartkopp &lt;socketcan@hartkopp.net&gt;
Link: https://patch.msgid.link/20260218-bcm_spin_lock_init-v1-1-592634c8a5b5@hartkopp.net
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>can: add drop reasons in CAN protocols receive path</title>
<updated>2025-06-10T08:23:56Z</updated>
<author>
<name>Davide Caratti</name>
</author>
<published>2025-06-04T16:06:05Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=81807451c2a6af59bbc58adfd0da69870c30d4ab'/>
<id>urn:sha1:81807451c2a6af59bbc58adfd0da69870c30d4ab</id>
<content type='text'>
sock_queue_rcv_skb() can fail because of lack of memory resources: use
drop reasons and pass the receiving socket to the tracepoint, so that
it's possible to better locate/debug such events.

Tested with:

| # modprobe vcan echo=1
| # ip link add name vcan2 type vcan
| # ip link set dev vcan2 up
| # ./netlayer/tst-proc 1 &amp;
| # bg
| # while true ; do perf record -e skb:kfree_skb -aR  -- \
| &gt; ./raw/tst-raw-sendto vcan2 ; perf script ; done
| [...]
| tst-raw-sendto 10942 [000] 506428.431856: skb:kfree_skb: skbaddr=0xffff97cec38b4200 rx_sk=0xffff97cf0f75a800 protocol=12 location=raw_rcv+0x20e reason: SOCKET_RCVBUF

Signed-off-by: Davide Caratti &lt;dcaratti@redhat.com&gt;
Link: https://patch.msgid.link/20250604160605.1005704-3-dcaratti@redhat.com
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
</content>
</entry>
<entry>
<title>can: bcm: add missing rcu read protection for procfs content</title>
<updated>2025-05-19T14:58:19Z</updated>
<author>
<name>Oliver Hartkopp</name>
</author>
<published>2025-05-19T12:50:27Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=dac5e6249159ac255dad9781793dbe5908ac9ddb'/>
<id>urn:sha1:dac5e6249159ac255dad9781793dbe5908ac9ddb</id>
<content type='text'>
When the procfs content is generated for a bcm_op which is in the process
to be removed the procfs output might show unreliable data (UAF).

As the removal of bcm_op's is already implemented with rcu handling this
patch adds the missing rcu_read_lock() and makes sure the list entries
are properly removed under rcu protection.

Fixes: f1b4e32aca08 ("can: bcm: use call_rcu() instead of costly synchronize_rcu()")
Reported-by: Anderson Nascimento &lt;anderson@allelesecurity.com&gt;
Suggested-by: Anderson Nascimento &lt;anderson@allelesecurity.com&gt;
Tested-by: Anderson Nascimento &lt;anderson@allelesecurity.com&gt;
Signed-off-by: Oliver Hartkopp &lt;socketcan@hartkopp.net&gt;
Link: https://patch.msgid.link/20250519125027.11900-2-socketcan@hartkopp.net
Cc: stable@vger.kernel.org # &gt;= 5.4
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
</content>
</entry>
<entry>
<title>can: bcm: add locking for bcm_op runtime updates</title>
<updated>2025-05-19T14:58:12Z</updated>
<author>
<name>Oliver Hartkopp</name>
</author>
<published>2025-05-19T12:50:26Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=c2aba69d0c36a496ab4f2e81e9c2b271f2693fd7'/>
<id>urn:sha1:c2aba69d0c36a496ab4f2e81e9c2b271f2693fd7</id>
<content type='text'>
The CAN broadcast manager (CAN BCM) can send a sequence of CAN frames via
hrtimer. The content and also the length of the sequence can be changed
resp reduced at runtime where the 'currframe' counter is then set to zero.

Although this appeared to be a safe operation the updates of 'currframe'
can be triggered from user space and hrtimer context in bcm_can_tx().
Anderson Nascimento created a proof of concept that triggered a KASAN
slab-out-of-bounds read access which can be prevented with a spin_lock_bh.

At the rework of bcm_can_tx() the 'count' variable has been moved into
the protected section as this variable can be modified from both contexts
too.

Fixes: ffd980f976e7 ("[CAN]: Add broadcast manager (bcm) protocol")
Reported-by: Anderson Nascimento &lt;anderson@allelesecurity.com&gt;
Tested-by: Anderson Nascimento &lt;anderson@allelesecurity.com&gt;
Reviewed-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Signed-off-by: Oliver Hartkopp &lt;socketcan@hartkopp.net&gt;
Link: https://patch.msgid.link/20250519125027.11900-1-socketcan@hartkopp.net
Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
</content>
</entry>
<entry>
<title>Merge tag 'net-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next</title>
<updated>2025-03-27T04:48:21Z</updated>
<author>
<name>Linus Torvalds</name>
</author>
<published>2025-03-27T04:48:21Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=1a9239bb4253f9076b5b4b2a1a4e8d7defd77a95'/>
<id>urn:sha1:1a9239bb4253f9076b5b4b2a1a4e8d7defd77a95</id>
<content type='text'>
Pull networking updates from Jakub Kicinski:
 "Core &amp; protocols:

   - Continue Netlink conversions to per-namespace RTNL lock
     (IPv4 routing, routing rules, routing next hops, ARP ioctls)

   - Continue extending the use of netdev instance locks. As a driver
     opt-in protect queue operations and (in due course) ethtool
     operations with the instance lock and not RTNL lock.

   - Support collecting TCP timestamps (data submitted, sent, acked) in
     BPF, allowing for transparent (to the application) and lower
     overhead tracking of TCP RPC performance.

   - Tweak existing networking Rx zero-copy infra to support zero-copy
     Rx via io_uring.

   - Optimize MPTCP performance in single subflow mode by 29%.

   - Enable GRO on packets which went thru XDP CPU redirect (were queued
     for processing on a different CPU). Improving TCP stream
     performance up to 2x.

   - Improve performance of contended connect() by 200% by searching for
     an available 4-tuple under RCU rather than a spin lock. Bring an
     additional 229% improvement by tweaking hash distribution.

   - Avoid unconditionally touching sk_tsflags on RX, improving
     performance under UDP flood by as much as 10%.

   - Avoid skb_clone() dance in ping_rcv() to improve performance under
     ping flood.

   - Avoid FIB lookup in netfilter if socket is available, 20% perf win.

   - Rework network device creation (in-kernel) API to more clearly
     identify network namespaces and their roles. There are up to 4
     namespace roles but we used to have just 2 netns pointer arguments,
     interpreted differently based on context.

   - Use sysfs_break_active_protection() instead of trylock to avoid
     deadlocks between unregistering objects and sysfs access.

   - Add a new sysctl and sockopt for capping max retransmit timeout in
     TCP.

   - Support masking port and DSCP in routing rule matches.

   - Support dumping IPv4 multicast addresses with RTM_GETMULTICAST.

   - Support specifying at what time packet should be sent on AF_XDP
     sockets.

   - Expose TCP ULP diagnostic info (for TLS and MPTCP) to non-admin
     users.

   - Add Netlink YAML spec for WiFi (nl80211) and conntrack.

   - Introduce EXPORT_IPV6_MOD() and EXPORT_IPV6_MOD_GPL() for symbols
     which only need to be exported when IPv6 support is built as a
     module.

   - Age FDB entries based on Rx not Tx traffic in VxLAN, similar to
     normal bridging.

   - Allow users to specify source port range for GENEVE tunnels.

   - netconsole: allow attaching kernel release, CPU ID and task name to
     messages as metadata

  Driver API:

   - Continue rework / fixing of Energy Efficient Ethernet (EEE) across
     the SW layers. Delegate the responsibilities to phylink where
     possible. Improve its handling in phylib.

   - Support symmetric OR-XOR RSS hashing algorithm.

   - Support tracking and preserving IRQ affinity by NAPI itself.

   - Support loopback mode speed selection for interface selftests.

  Device drivers:

   - Remove the IBM LCS driver for s390

   - Remove the sb1000 cable modem driver

   - Add support for SFP module access over SMBus

   - Add MCTP transport driver for MCTP-over-USB

   - Enable XDP metadata support in multiple drivers

   - Ethernet high-speed NICs:
      - Broadcom (bnxt):
         - add PCIe TLP Processing Hints (TPH) support for new AMD
           platforms
         - support dumping RoCE queue state for debug
         - opt into instance locking
      - Intel (100G, ice, idpf):
         - ice: rework MSI-X IRQ management and distribution
         - ice: support for E830 devices
         - iavf: add support for Rx timestamping
         - iavf: opt into instance locking
      - nVidia/Mellanox:
         - mlx4: use page pool memory allocator for Rx
         - mlx5: support for one PTP device per hardware clock
         - mlx5: support for 200Gbps per-lane link modes
         - mlx5: move IPSec policy check after decryption
      - AMD/Solarflare:
         - support FW flashing via devlink
      - Cisco (enic):
         - use page pool memory allocator for Rx
         - enable 32, 64 byte CQEs
         - get max rx/tx ring size from the device
      - Meta (fbnic):
         - support flow steering and RSS configuration
         - report queue stats
         - support TCP segmentation
         - support IRQ coalescing
         - support ring size configuration
      - Marvell/Cavium:
         - support AF_XDP
      - Wangxun:
         - support for PTP clock and timestamping
      - Huawei (hibmcge):
         - checksum offload
         - add more statistics

   - Ethernet virtual:
      - VirtIO net:
         - aggressively suppress Tx completions, improve perf by 96%
           with 1 CPU and 55% with 2 CPUs
         - expose NAPI to IRQ mapping and persist NAPI settings
      - Google (gve):
         - support XDP in DQO RDA Queue Format
         - opt into instance locking
      - Microsoft vNIC:
         - support BIG TCP

   - Ethernet NICs consumer, and embedded:
      - Synopsys (stmmac):
         - cleanup Tx and Tx clock setting and other link-focused
           cleanups
         - enable SGMII and 2500BASEX mode switching for Intel platforms
         - support Sophgo SG2044
      - Broadcom switches (b53):
         - support for BCM53101
      - TI:
         - iep: add perout configuration support
         - icssg: support XDP
      - Cadence (macb):
         - implement BQL
      - Xilinx (axinet):
         - support dynamic IRQ moderation and changing coalescing at
           runtime
         - implement BQL
         - report standard stats
      - MediaTek:
         - support phylink managed EEE
      - Intel:
         - igc: don't restart the interface on every XDP program change
      - RealTek (r8169):
         - support reading registers of internal PHYs directly
         - increase max jumbo packet size on RTL8125/RTL8126
      - Airoha:
         - support for RISC-V NPU packet processing unit
         - enable scatter-gather and support MTU up to 9kB
      - Tehuti (tn40xx):
         - support cards with TN4010 MAC and an Aquantia AQR105 PHY

   - Ethernet PHYs:
      - support for TJA1102S, TJA1121
      - dp83tg720: add randomized polling intervals for link detection
      - dp83822: support changing the transmit amplitude voltage
      - support for LEDs on 88q2xxx

   - CAN:
      - canxl: support Remote Request Substitution bit access
      - flexcan: add S32G2/S32G3 SoC

   - WiFi:
      - remove cooked monitor support
      - strict mode for better AP testing
      - basic EPCS support
      - OMI RX bandwidth reduction support
      - batman-adv: add support for jumbo frames

   - WiFi drivers:
      - RealTek (rtw88):
         - support RTL8814AE and RTL8814AU
      - RealTek (rtw89):
         - switch using wiphy_lock and wiphy_work
         - add BB context to manipulate two PHY as preparation of MLO
         - improve BT-coexistence mechanism to play A2DP smoothly
      - Intel (iwlwifi):
         - add new iwlmld sub-driver for latest HW/FW combinations
      - MediaTek (mt76):
         - preparation for mt7996 Multi-Link Operation (MLO) support
      - Qualcomm/Atheros (ath12k):
         - continued work on MLO
      - Silabs (wfx):
         - Wake-on-WLAN support

   - Bluetooth:
      - add support for skb TX SND/COMPLETION timestamping
      - hci_core: enable buffer flow control for SCO/eSCO
      - coredump: log devcd dumps into the monitor

   - Bluetooth drivers:
      - intel: add support to configure TX power
      - nxp: handle bootloader error during cmd5 and cmd7"

* tag 'net-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1681 commits)
  unix: fix up for "apparmor: add fine grained af_unix mediation"
  mctp: Fix incorrect tx flow invalidation condition in mctp-i2c
  net: usb: asix: ax88772: Increase phy_name size
  net: phy: Introduce PHY_ID_SIZE — minimum size for PHY ID string
  net: libwx: fix Tx L4 checksum
  net: libwx: fix Tx descriptor content for some tunnel packets
  atm: Fix NULL pointer dereference
  net: tn40xx: add pci-id of the aqr105-based Tehuti TN4010 cards
  net: tn40xx: prepare tn40xx driver to find phy of the TN9510 card
  net: tn40xx: create swnode for mdio and aqr105 phy and add to mdiobus
  net: phy: aquantia: add essential functions to aqr105 driver
  net: phy: aquantia: search for firmware-name in fwnode
  net: phy: aquantia: add probe function to aqr105 for firmware loading
  net: phy: Add swnode support to mdiobus_scan
  gve: add XDP DROP and PASS support for DQ
  gve: update XDP allocation path support RX buffer posting
  gve: merge packet buffer size fields
  gve: update GQ RX to use buf_size
  gve: introduce config-based allocation for XDP
  gve: remove xdp_xsk_done and xdp_xsk_wakeup statistics
  ...
</content>
</entry>
<entry>
<title>can: add protocol counter for AF_CAN sockets</title>
<updated>2025-03-14T12:27:33Z</updated>
<author>
<name>Davide Caratti</name>
</author>
<published>2025-03-14T11:39:49Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=6bffe88452dbe284747442f10a7ac8249d6495d7'/>
<id>urn:sha1:6bffe88452dbe284747442f10a7ac8249d6495d7</id>
<content type='text'>
The third column in the output of the following command:

| # grep CAN /proc/net/protocols

is systematically '0': use sock_prot_inuse_add() to account for the number
of sockets for each protocol on top of AF_CAN family.

Signed-off-by: Davide Caratti &lt;dcaratti@redhat.com&gt;
Link: https://patch.msgid.link/9db5d0e6c11b232ad895885616f1258882a32f61.1741952160.git.dcaratti@redhat.com
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
</content>
</entry>
<entry>
<title>can: Switch to use hrtimer_setup()</title>
<updated>2025-02-18T09:35:45Z</updated>
<author>
<name>Nam Cao</name>
</author>
<published>2025-02-05T10:43:27Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=806e32248e22582715dbbb7664567b81b9d6928a'/>
<id>urn:sha1:806e32248e22582715dbbb7664567b81b9d6928a</id>
<content type='text'>
hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.

Replace hrtimer_init() and the open coded initialization of
hrtimer::function with the new setup mechanism.

Most of this patch is generated by Coccinelle. Except for the TX thrtimer
in bcm_tx_setup() because this timer is not used and the callback function
is never set. For this particular case, set the callback to
hrtimer_dummy_timeout()

Signed-off-by: Nam Cao &lt;namcao@linutronix.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Link: https://lore.kernel.org/all/a3a6be42c818722ad41758457408a32163bfd9a0.1738746872.git.namcao@linutronix.de

</content>
</entry>
<entry>
<title>can: bcm: Clear bo-&gt;bcm_proc_read after remove_proc_entry().</title>
<updated>2024-09-12T07:40:08Z</updated>
<author>
<name>Kuniyuki Iwashima</name>
</author>
<published>2024-09-05T01:22:37Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=94b0818fa63555a65f6ba107080659ea6bcca63e'/>
<id>urn:sha1:94b0818fa63555a65f6ba107080659ea6bcca63e</id>
<content type='text'>
syzbot reported a warning in bcm_release(). [0]

The blamed change fixed another warning that is triggered when
connect() is issued again for a socket whose connect()ed device has
been unregistered.

However, if the socket is just close()d without the 2nd connect(), the
remaining bo-&gt;bcm_proc_read triggers unnecessary remove_proc_entry()
in bcm_release().

Let's clear bo-&gt;bcm_proc_read after remove_proc_entry() in bcm_notify().

[0]
name '4986'
WARNING: CPU: 0 PID: 5234 at fs/proc/generic.c:711 remove_proc_entry+0x2e7/0x5d0 fs/proc/generic.c:711
Modules linked in:
CPU: 0 UID: 0 PID: 5234 Comm: syz-executor606 Not tainted 6.11.0-rc5-syzkaller-00178-g5517ae241919 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:remove_proc_entry+0x2e7/0x5d0 fs/proc/generic.c:711
Code: ff eb 05 e8 cb 1e 5e ff 48 8b 5c 24 10 48 c7 c7 e0 f7 aa 8e e8 2a 38 8e 09 90 48 c7 c7 60 3a 1b 8c 48 89 de e8 da 42 20 ff 90 &lt;0f&gt; 0b 90 90 48 8b 44 24 18 48 c7 44 24 40 0e 36 e0 45 49 c7 04 07
RSP: 0018:ffffc9000345fa20 EFLAGS: 00010246
RAX: 2a2d0aee2eb64600 RBX: ffff888032f1f548 RCX: ffff888029431e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000345fb08 R08: ffffffff8155b2f2 R09: 1ffff1101710519a
R10: dffffc0000000000 R11: ffffed101710519b R12: ffff888011d38640
R13: 0000000000000004 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcfb52722f0 CR3: 000000000e734000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 &lt;TASK&gt;
 bcm_release+0x250/0x880 net/can/bcm.c:1578
 __sock_release net/socket.c:659 [inline]
 sock_close+0xbc/0x240 net/socket.c:1421
 __fput+0x24a/0x8a0 fs/file_table.c:422
 task_work_run+0x24f/0x310 kernel/task_work.c:228
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xa2f/0x27f0 kernel/exit.c:882
 do_group_exit+0x207/0x2c0 kernel/exit.c:1031
 __do_sys_exit_group kernel/exit.c:1042 [inline]
 __se_sys_exit_group kernel/exit.c:1040 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040
 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcfb51ee969
Code: Unable to access opcode bytes at 0x7fcfb51ee93f.
RSP: 002b:00007ffce0109ca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fcfb51ee969
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 00007fcfb526f3b0 R08: ffffffffffffffb8 R09: 0000555500000000
R10: 0000555500000000 R11: 0000000000000246 R12: 00007fcfb526f3b0
R13: 0000000000000000 R14: 00007fcfb5271ee0 R15: 00007fcfb51bf160
 &lt;/TASK&gt;

Fixes: 76fe372ccb81 ("can: bcm: Remove proc entry when dev is unregistered.")
Reported-by: syzbot+0532ac7a06fb1a03187e@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0532ac7a06fb1a03187e
Tested-by: syzbot+0532ac7a06fb1a03187e@syzkaller.appspotmail.com
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Reviewed-by: Vincent Mailhol &lt;mailhol.vincent@wanadoo.fr&gt;
Link: https://patch.msgid.link/20240905012237.79683-1-kuniyu@amazon.com
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
</content>
</entry>
<entry>
<title>can: bcm: Remove proc entry when dev is unregistered.</title>
<updated>2024-08-06T07:25:12Z</updated>
<author>
<name>Kuniyuki Iwashima</name>
</author>
<published>2024-07-22T19:28:42Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=76fe372ccb81b0c89b6cd2fec26e2f38c958be85'/>
<id>urn:sha1:76fe372ccb81b0c89b6cd2fec26e2f38c958be85</id>
<content type='text'>
syzkaller reported a warning in bcm_connect() below. [0]

The repro calls connect() to vxcan1, removes vxcan1, and calls
connect() with ifindex == 0.

Calling connect() for a BCM socket allocates a proc entry.
Then, bcm_sk(sk)-&gt;bound is set to 1 to prevent further connect().

However, removing the bound device resets bcm_sk(sk)-&gt;bound to 0
in bcm_notify().

The 2nd connect() tries to allocate a proc entry with the same
name and sets NULL to bcm_sk(sk)-&gt;bcm_proc_read, leaking the
original proc entry.

Since the proc entry is available only for connect()ed sockets,
let's clean up the entry when the bound netdev is unregistered.

[0]:
proc_dir_entry 'can-bcm/2456' already registered
WARNING: CPU: 1 PID: 394 at fs/proc/generic.c:376 proc_register+0x645/0x8f0 fs/proc/generic.c:375
Modules linked in:
CPU: 1 PID: 394 Comm: syz-executor403 Not tainted 6.10.0-rc7-g852e42cc2dd4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
RIP: 0010:proc_register+0x645/0x8f0 fs/proc/generic.c:375
Code: 00 00 00 00 00 48 85 ed 0f 85 97 02 00 00 4d 85 f6 0f 85 9f 02 00 00 48 c7 c7 9b cb cf 87 48 89 de 4c 89 fa e8 1c 6f eb fe 90 &lt;0f&gt; 0b 90 90 48 c7 c7 98 37 99 89 e8 cb 7e 22 05 bb 00 00 00 10 48
RSP: 0018:ffa0000000cd7c30 EFLAGS: 00010246
RAX: 9e129be1950f0200 RBX: ff1100011b51582c RCX: ff1100011857cd80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: 0000000000000000 R08: ffd400000000000f R09: ff1100013e78cac0
R10: ffac800000cd7980 R11: ff1100013e12b1f0 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ff1100011a99a2ec
FS:  00007fbd7086f740(0000) GS:ff1100013fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200071c0 CR3: 0000000118556004 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 &lt;TASK&gt;
 proc_create_net_single+0x144/0x210 fs/proc/proc_net.c:220
 bcm_connect+0x472/0x840 net/can/bcm.c:1673
 __sys_connect_file net/socket.c:2049 [inline]
 __sys_connect+0x5d2/0x690 net/socket.c:2066
 __do_sys_connect net/socket.c:2076 [inline]
 __se_sys_connect net/socket.c:2073 [inline]
 __x64_sys_connect+0x8f/0x100 net/socket.c:2073
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7fbd708b0e5d
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d 73 9f 1b 00 f7 d8 64 89 01 48
RSP: 002b:00007fff8cd33f08 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fbd708b0e5d
RDX: 0000000000000010 RSI: 0000000020000040 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000040 R09: 0000000000000040
R10: 0000000000000040 R11: 0000000000000246 R12: 00007fff8cd34098
R13: 0000000000401280 R14: 0000000000406de8 R15: 00007fbd70ab9000
 &lt;/TASK&gt;
remove_proc_entry: removing non-empty directory 'net/can-bcm', leaking at least '2456'

Fixes: ffd980f976e7 ("[CAN]: Add broadcast manager (bcm) protocol")
Reported-by: syzkaller &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://lore.kernel.org/all/20240722192842.37421-1-kuniyu@amazon.com
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
</content>
</entry>
<entry>
<title>can: bcm: add recvmsg flags for own, local and remote traffic</title>
<updated>2024-02-12T15:55:17Z</updated>
<author>
<name>Nicolas Maier</name>
</author>
<published>2024-01-20T08:10:18Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=fec846fa7eddf7bb651bf88bd78c7db1410ae3b1'/>
<id>urn:sha1:fec846fa7eddf7bb651bf88bd78c7db1410ae3b1</id>
<content type='text'>
CAN RAW sockets allow userspace to tell if a received CAN frame comes
from the same socket, another socket on the same host, or another host.
See commit 1e55659ce6dd ("can-raw: add msg_flags to distinguish local
traffic"). However, this feature is missing in CAN BCM sockets.

Add the same feature to CAN BCM sockets. When reading a received frame
(opcode RX_CHANGED) using recvmsg, two flags in msg-&gt;msg_flags may be
set following the previous convention (from CAN RAW), to distinguish
between 'own', 'local' and 'remote' CAN traffic.

Update the documentation to reflect this change.

Signed-off-by: Nicolas Maier &lt;nicolas.maier.dev@gmail.com&gt;
Signed-off-by: Oliver Hartkopp &lt;socketcan@hartkopp.net&gt;
Link: https://lore.kernel.org/all/20240120081018.2319-1-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
</content>
</entry>
</feed>
