kernel/linux.git/include/net/nfc/nfc.h, branch v6.19.12

nfc: nci: Fix race between rfkill and nci_unregister_device().

2026-01-29T03:32:26+00:00

syzbot reported the splat below [0] without a repro. It indicates that struct nci_dev.cmd_wq had been destroyed before nci_close_device() was called via rfkill. nci_dev.cmd_wq is only destroyed in nci_unregister_device(), which (I think) was called from virtual_ncidev_close() when syzbot close()d an fd of virtual_ncidev. The problem is that nci_unregister_device() destroys nci_dev.cmd_wq first and then calls nfc_unregister_device(), which removes the device from rfkill by rfkill_unregister(). So, the device is still visible via rfkill even after nci_dev.cmd_wq is destroyed. Let's unregister the device from rfkill first in nci_unregister_device(). Note that we cannot call nfc_unregister_device() before nci_close_device() because 1) nfc_unregister_device() calls device_del() which frees all memory allocated by devm_kzalloc() and linked to ndev->conn_info_list 2) nci_rx_work() could try to queue nci_conn_info to ndev->conn_info_list which could be leaked Thus, nfc_unregister_device() is split into two functions so we can remove rfkill interfaces only before nci_close_device(). [0]: DEBUG_LOCKS_WARN_ON(1) WARNING: kernel/locking/lockdep.c:238 at hlock_class kernel/locking/lockdep.c:238 [inline], CPU#0: syz.0.8675/6349 WARNING: kernel/locking/lockdep.c:238 at check_wait_context kernel/locking/lockdep.c:4854 [inline], CPU#0: syz.0.8675/6349 WARNING: kernel/locking/lockdep.c:238 at __lock_acquire+0x39d/0x2cf0 kernel/locking/lockdep.c:5187, CPU#0: syz.0.8675/6349 Modules linked in: CPU: 0 UID: 0 PID: 6349 Comm: syz.0.8675 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 RIP: 0010:hlock_class kernel/locking/lockdep.c:238 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4854 [inline] RIP: 0010:__lock_acquire+0x3a4/0x2cf0 kernel/locking/lockdep.c:5187 Code: 18 00 4c 8b 74 24 08 75 27 90 e8 17 f2 fc 02 85 c0 74 1c 83 3d 50 e0 4e 0e 00 75 13 48 8d 3d 43 f7 51 0e 48 c7 c6 8b 3a de 8d <67> 48 0f b9 3a 90 31 c0 0f b6 98 c4 00 00 00 41 8b 45 20 25 ff 1f RSP: 0018:ffffc9000c767680 EFLAGS: 00010046 RAX: 0000000000000001 RBX: 0000000000040000 RCX: 0000000000080000 RDX: ffffc90013080000 RSI: ffffffff8dde3a8b RDI: ffffffff8ff24ca0 RBP: 0000000000000003 R08: ffffffff8fef35a3 R09: 1ffffffff1fde6b4 R10: dffffc0000000000 R11: fffffbfff1fde6b5 R12: 00000000000012a2 R13: ffff888030338ba8 R14: ffff888030338000 R15: ffff888030338b30 FS: 00007fa5995f66c0(0000) GS:ffff8881256f8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7e72f842d0 CR3: 00000000485a0000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868 touch_wq_lockdep_map+0xcb/0x180 kernel/workqueue.c:3940 __flush_workqueue+0x14b/0x14f0 kernel/workqueue.c:3982 nci_close_device+0x302/0x630 net/nfc/nci/core.c:567 nci_dev_down+0x3b/0x50 net/nfc/nci/core.c:639 nfc_dev_down+0x152/0x290 net/nfc/core.c:161 nfc_rfkill_set_block+0x2d/0x100 net/nfc/core.c:179 rfkill_set_block+0x1d2/0x440 net/rfkill/core.c:346 rfkill_fop_write+0x461/0x5a0 net/rfkill/core.c:1301 vfs_write+0x29a/0xb90 fs/read_write.c:684 ksys_write+0x150/0x270 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa59b39acb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa5995f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa59b615fa0 RCX: 00007fa59b39acb9 RDX: 0000000000000008 RSI: 0000200000000080 RDI: 0000000000000007 RBP: 00007fa59b408bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa59b616038 R14: 00007fa59b615fa0 R15: 00007ffc82218788 Fixes: 6a2968aaf50c ("NFC: basic NCI protocol implementation") Reported-by: syzbot+f9c5fd1a0874f9069dce@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/695e7f56.050a0220.1c677c.036c.GAE@google.com/ Signed-off-by: Kuniyuki Iwashima Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260127040411.494931-1-kuniyu@google.com Signed-off-by: Jakub Kicinski

net: nfc: Propagate ISO14443 type A target ATS to userspace via netlink

2024-11-07T09:21:58+00:00

Add a 20-byte field ats to struct nfc_target and expose it as NFC_ATTR_TARGET_ATS via the netlink interface. The payload contains 'historical bytes' that help to distinguish cards from one another. The information is commonly used to assemble an emulated ATR similar to that reported by smart cards with contacts. Add a 20-byte field target_ats to struct nci_dev to hold the payload obtained in nci_rf_intf_activated_ntf_packet() and copy it to over to nfc_target.ats in nci_activate_target(). The approach is similar to the handling of 'general bytes' within ATR_RES. Replace the hard-coded size of rats_res within struct activation_params_nfca_poll_iso_dep by the equal constant NFC_ATS_MAXSIZE now defined in nfc.h Within NCI, the information corresponds to the 'RATS Response' activation parameter that omits the initial length byte TL. This loses no information and is consistent with our handling of SENSB_RES that also drops the first (constant) byte. Tested with nxp_nci_i2c on a few type A targets including an ICAO 9303 compliant passport. I refrain from the corresponding change to digital_in_recv_ats() to have the few drivers based on digital.h fill nfc_target.ats, as I have no way to test it. That class of drivers appear not to set NFC_ATTR_TARGET_SENSB_RES either. Consider a separate patch to propagate (all) the parameters. Signed-off-by: Juraj Šarinay Link: https://patch.msgid.link/20241103124525.8392-1-juraj@sarinay.com Signed-off-by: Paolo Abeni

NFC: Correct spelling in headers

2024-08-26T16:37:23+00:00

Correct spelling in NFC headers. As reported by codespell. Signed-off-by: Simon Horman Reviewed-by: Krzysztof Kozlowski Link: https://patch.msgid.link/20240822-net-spell-v1-8-3a98971ce2d2@kernel.org Signed-off-by: Jakub Kicinski

nfc: core: make nfc_class constant

2024-03-05T19:21:18+00:00

Since commit 43a7206b0963 ("driver core: class: make class_register() take a const *"), the driver core allows for struct class to be in read-only memory, so move the nfc_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at boot time. Suggested-by: Greg Kroah-Hartman Signed-off-by: Ricardo B. Marliere Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20240302-class_cleanup-net-next-v1-6-8fa378595b93@marliere.net Signed-off-by: Jakub Kicinski

nfc: constify several pointers to u8, char and sk_buff

2021-07-30T15:22:52+00:00

Several functions receive pointers to u8, char or sk_buff but do not modify the contents so make them const. This allows doing the same for local variables and in total makes the code a little bit safer. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Jakub Kicinski

nfc: constify passed nfc_dev

2021-07-29T11:28:02+00:00

The struct nfc_dev is not modified by nfc_get_drvdata() and nfc_device_name() so it can be made a const. Signed-off-by: Krzysztof Kozlowski Signed-off-by: David S. Miller

nfc: constify nfc_ops

2021-07-25T08:21:21+00:00

Neither the core nor the drivers modify the passed pointer to struct nfc_ops, so make it a pointer to const for correctness and safety. Signed-off-by: Krzysztof Kozlowski Signed-off-by: David S. Miller

nfc: constify pointer to nfc_vendor_cmd

2021-07-25T08:21:21+00:00

Neither the core nor the drivers modify the passed pointer to struct nfc_vendor_cmd, so make it a pointer to const for correctness and safety. Signed-off-by: Krzysztof Kozlowski Signed-off-by: David S. Miller

NFC: Replace zero-length array with flexible-array member

2020-02-27T20:06:20+00:00

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13

2019-05-21T09:28:45+00:00

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details [based] [from] [clk] [highbank] [c] you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 355 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Kate Stewart Reviewed-by: Jilayne Lovejoy Reviewed-by: Steve Winslow Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154041.837383322@linutronix.de Signed-off-by: Greg Kroah-Hartman