kernel/linux.git/net/caif, branch v6.1.168

caif: fix integer underflow in cffrml_receive()

2026-01-11T14:18:42+00:00

[ Upstream commit 8a11ff0948b5ad09b71896b7ccc850625f9878d1 ] The cffrml_receive() function extracts a length field from the packet header and, when FCS is disabled, subtracts 2 from this length without validating that len >= 2. If an attacker sends a malicious packet with a length field of 0 or 1 to an interface with FCS disabled, the subtraction causes an integer underflow. This can lead to memory exhaustion and kernel instability, potential information disclosure if padding contains uninitialized kernel memory. Fix this by validating that len >= 2 before performing the subtraction. Reported-by: Yuhao Jiang Reported-by: Junrui Luo Fixes: b482cd2053e3 ("net-caif: add CAIF core protocol stack") Signed-off-by: Junrui Luo Reviewed-by: Simon Horman Link: https://patch.msgid.link/SYBPR01MB7881511122BAFEA8212A1608AFA6A@SYBPR01MB7881.ausprd01.prod.outlook.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

caif: reduce stack size, again

2025-08-15T10:04:56+00:00

[ Upstream commit b630c781bcf6ff87657146661816d0d30a902139 ] I tried to fix the stack usage in this function a couple of years ago, but there is still a problem with the latest gcc versions in some configurations: net/caif/cfctrl.c:553:1: error: the frame size of 1296 bytes is larger than 1280 bytes [-Werror=frame-larger-than=] Reduce this once again, with a separate cfctrl_link_setup() function that holds the bulk of all the local variables. It also turns out that the param[] array that takes up a large portion of the stack is write-only and can be left out here. Fixes: ce6289661b14 ("caif: reduce stack size with KASAN") Signed-off-by: Arnd Bergmann Link: https://patch.msgid.link/20250620112244.3425554-1-arnd@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: caif: Fix use-after-free in cfusbl_device_notify()

2023-03-17T07:50:24+00:00

[ Upstream commit 9781e98a97110f5e76999058368b4be76a788484 ] syzbot reported use-after-free in cfusbl_device_notify() [1]. This causes a stack trace like below: BUG: KASAN: use-after-free in cfusbl_device_notify+0x7c9/0x870 net/caif/caif_usb.c:138 Read of size 8 at addr ffff88807ac4e6f0 by task kworker/u4:6/1214 CPU: 0 PID: 1214 Comm: kworker/u4:6 Not tainted 5.19.0-rc3-syzkaller-00146-g92f20ff72066 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x467 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 cfusbl_device_notify+0x7c9/0x870 net/caif/caif_usb.c:138 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945 call_netdevice_notifiers_extack net/core/dev.c:1983 [inline] call_netdevice_notifiers net/core/dev.c:1997 [inline] netdev_wait_allrefs_any net/core/dev.c:10227 [inline] netdev_run_todo+0xbc0/0x10f0 net/core/dev.c:10341 default_device_exit_batch+0x44e/0x590 net/core/dev.c:11334 ops_exit_list+0x125/0x170 net/core/net_namespace.c:167 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:594 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 When unregistering a net device, unregister_netdevice_many_notify() sets the device's reg_state to NETREG_UNREGISTERING, calls notifiers with NETDEV_UNREGISTER, and adds the device to the todo list. Later on, devices in the todo list are processed by netdev_run_todo(). netdev_run_todo() waits devices' reference count become 1 while rebdoadcasting NETDEV_UNREGISTER notification. When cfusbl_device_notify() is called with NETDEV_UNREGISTER multiple times, the parent device might be freed. This could cause UAF. Processing NETDEV_UNREGISTER multiple times also causes inbalance of reference count for the module. This patch fixes the issue by accepting only first NETDEV_UNREGISTER notification. Fixes: 7ad65bf68d70 ("caif: Add support for CAIF over CDC NCM USB interface") CC: sjur.brandeland@stericsson.com Reported-by: syzbot+b563d33852b893653a9e@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?id=c3bfd8e2450adab3bffe4d80821fbbced600407f [1] Signed-off-by: Shigeru Yoshida Link: https://lore.kernel.org/r/20230301163913.391304-1-syoshida@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: Remove WARN_ON_ONCE(sk->sk_forward_alloc) from sk_stream_kill_queues().

2023-03-03T10:52:23+00:00

commit 62ec33b44e0f7168ff2886520fec6fb62d03b5a3 upstream. Christoph Paasch reported that commit b5fc29233d28 ("inet6: Remove inet6_destroy_sock() in sk->sk_prot->destroy().") started triggering WARN_ON_ONCE(sk->sk_forward_alloc) in sk_stream_kill_queues(). [0 - 2] Also, we can reproduce it by a program in [3]. In the commit, we delay freeing ipv6_pinfo.pktoptions from sk->destroy() to sk->sk_destruct(), so sk->sk_forward_alloc is no longer zero in inet_csk_destroy_sock(). The same check has been in inet_sock_destruct() from at least v2.6, we can just remove the WARN_ON_ONCE(). However, among the users of sk_stream_kill_queues(), only CAIF is not calling inet_sock_destruct(). Thus, we add the same WARN_ON_ONCE() to caif_sock_destructor(). [0]: https://lore.kernel.org/netdev/39725AB4-88F1-41B3-B07F-949C5CAEFF4F@icloud.com/ [1]: https://github.com/multipath-tcp/mptcp_net-next/issues/341 [2]: WARNING: CPU: 0 PID: 3232 at net/core/stream.c:212 sk_stream_kill_queues+0x2f9/0x3e0 Modules linked in: CPU: 0 PID: 3232 Comm: syz-executor.0 Not tainted 6.2.0-rc5ab24eb4698afbe147b424149c529e2a43ec24eb5 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:sk_stream_kill_queues+0x2f9/0x3e0 Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e ec 00 00 00 8b ab 08 01 00 00 e9 60 ff ff ff e8 d0 5f b6 fe 0f 0b eb 97 e8 c7 5f b6 fe <0f> 0b eb a0 e8 be 5f b6 fe 0f 0b e9 6a fe ff ff e8 02 07 e3 fe e9 RSP: 0018:ffff88810570fc68 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888101f38f40 RSI: ffffffff8285e529 RDI: 0000000000000005 RBP: 0000000000000ce0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000ce0 R11: 0000000000000001 R12: ffff8881009e9488 R13: ffffffff84af2cc0 R14: 0000000000000000 R15: ffff8881009e9458 FS: 00007f7fdfbd5800(0000) GS:ffff88811b600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32923000 CR3: 00000001062fc006 CR4: 0000000000170ef0 Call Trace: inet_csk_destroy_sock+0x1a1/0x320 __tcp_close+0xab6/0xe90 tcp_close+0x30/0xc0 inet_release+0xe9/0x1f0 inet6_release+0x4c/0x70 __sock_release+0xd2/0x280 sock_close+0x15/0x20 __fput+0x252/0xa20 task_work_run+0x169/0x250 exit_to_user_mode_prepare+0x113/0x120 syscall_exit_to_user_mode+0x1d/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f7fdf7ae28d Code: c1 20 00 00 75 10 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee fb ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 37 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00000000007dfbb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f7fdf7ae28d RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000003 RBP: 0000000000000000 R08: 000000007f338e0f R09: 0000000000000e0f R10: 000000007f338e13 R11: 0000000000000293 R12: 00007f7fdefff000 R13: 00007f7fdefffcd8 R14: 00007f7fdefffce0 R15: 00007f7fdefffcd8 [3]: https://lore.kernel.org/netdev/20230208004245.83497-1-kuniyu@amazon.com/ Fixes: b5fc29233d28 ("inet6: Remove inet6_destroy_sock() in sk->sk_prot->destroy().") Reported-by: syzbot Reported-by: Christoph Paasch Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

caif: fix memory leak in cfctrl_linkup_request()

2023-01-12T11:02:33+00:00

[ Upstream commit fe69230f05897b3de758427b574fc98025dfc907 ] When linktype is unknown or kzalloc failed in cfctrl_linkup_request(), pkt is not released. Add release process to error path. Fixes: b482cd2053e3 ("net-caif: add CAIF core protocol stack") Fixes: 8d545c8f958f ("caif: Disconnect without waiting for response") Signed-off-by: Zhengchao Shao Reviewed-by: Jiri Pirko Link: https://lore.kernel.org/r/20230104065146.1153009-1-shaozhengchao@huawei.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: caif: fix double disconnect client in chnl_net_open()

2022-11-14T10:51:13+00:00

When connecting to client timeout, disconnect client for twice in chnl_net_open(). Remove one. Compile tested only. Fixes: 2aa40aef9deb ("caif: Use link layer MTU instead of fixed MTU") Signed-off-by: Zhengchao Shao Signed-off-by: David S. Miller

caif: move from strlcpy with unused retval to strscpy

2022-08-23T00:57:35+00:00

Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang Link: https://lore.kernel.org/r/20220818210214.8371-1-wsa+renesas@sang-engineering.com Signed-off-by: Jakub Kicinski

caif: Fix bitmap data type in "struct caifsock"

2022-07-22T11:51:45+00:00

Bitmap are "unsigned long", so use it instead of a "u32" to make things more explicit. While at it, remove some useless cast (and leading spaces) when using the bitmap API. Signed-off-by: Christophe JAILLET Signed-off-by: David S. Miller

net: remove noblock parameter from skb_recv_datagram()

2022-04-06T12:45:26+00:00

skb_recv_datagram() has two parameters 'flags' and 'noblock' that are merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)' As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags' into 'flags' and 'noblock' with finally obsolete bit operations like this: skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc); And this is not even done consistently with the 'flags' parameter. This patch removes the obsolete and costly splitting into two parameters and only performs bit operations when really needed on the caller side. One missing conversion thankfully reported by kernel test robot. I missed to enable kunit tests to build the mctp code. Reported-by: kernel test robot Signed-off-by: Oliver Hartkopp Signed-off-by: David S. Miller

net: caif: Use netif_rx().

2022-03-04T12:02:19+00:00

Since commit baebdf48c3600 ("net: dev: Makes sure netif_rx() can be invoked in any context.") the function netif_rx() can be used in preemptible/thread context as well as in interrupt context. Use netif_rx(). Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: David S. Miller