kernel/net/nfc/netlink.c, branch linux-rolling-stable

nfc: Remove checks for nla_data returning NULL

2025-06-18T21:17:32Z

The implementation of nla_data is as follows: static inline void *nla_data(const struct nlattr *nla) { return (char *) nla + NLA_HDRLEN; } Excluding the case where nla is exactly -NLA_HDRLEN, it will not return NULL. And it seems misleading to assume that it can, other than in this corner case. So drop checks for this condition. Flagged by Smatch. Compile tested only. Signed-off-by: Simon Horman Reviewed-by: Krzysztof Kozlowski Link: https://patch.msgid.link/20250617-nfc-null-data-v1-1-c7525ead2e95@kernel.org Signed-off-by: Jakub Kicinski

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

2024-11-07T09:21:58Z

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

net: nfc: remove inappropriate attrs check

2024-04-13T01:52:35Z

Revert "NFC: fix attrs checks in netlink interface" This reverts commit 18917d51472fe3b126a3a8f756c6b18085eb8130. Our checks found weird attrs present check in function nfc_genl_dep_link_down() and nfc_genl_llc_get_params(), which are introduced by commit 18917d51472f ("NFC: fix attrs checks in netlink interface"). According to its message, it should add checks for functions nfc_genl_deactivate_target() and nfc_genl_fw_download(). However, it didn't do that. In fact, the expected checks are added by (1) commit 385097a36757 ("nfc: Ensure presence of required attributes in the deactivate_target handler") and (2) commit 280e3ebdafb8 ("nfc: Ensure presence of NFC_ATTR_FIRMWARE_NAME attribute in nfc_genl_fw_download()"). Perhaps something went wrong. Anyway, the attr NFC_ATTR_TARGET_INDEX is never accessed in callback nfc_genl_dep_link_down() and same for NFC_ATTR_FIRMWARE_NAME and nfc_genl_llc_get_params(). Thus, remove those checks. Signed-off-by: Lin Ma Link: https://lore.kernel.org/r/20240410034846.167421-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski

genetlink: use attrs from struct genl_info

2023-08-15T22:00:45Z

Since dumps carry struct genl_info now, use the attrs pointer from genl_info and remove the one in struct genl_dumpit_info. Reviewed-by: Johannes Berg Reviewed-by: Miquel Raynal Reviewed-by: Jiri Pirko Link: https://lore.kernel.org/r/20230814214723.2924989-6-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: nfc: Fix use-after-free caused by nfc_llcp_find_local

2023-06-26T09:57:23Z

This commit fixes several use-after-free that caused by function nfc_llcp_find_local(). For example, one UAF can happen when below buggy time window occurs. // nfc_genl_llc_get_params | // nfc_unregister_device | dev = nfc_get_device(idx); | device_lock(...) if (!dev) | dev->shutting_down = true; return -ENODEV; | device_unlock(...); | device_lock(...); | // nfc_llcp_unregister_device | nfc_llcp_find_local() nfc_llcp_find_local(...); | | local_cleanup() if (!local) { | rc = -ENODEV; | // nfc_llcp_local_put goto exit; | kref_put(.., local_release) } | | // local_release | list_del(&local->list) // nfc_genl_send_params | kfree() local->dev->idx !!!UAF!!! | | and the crash trace for the one of the discussed UAF like: BUG: KASAN: slab-use-after-free in nfc_genl_llc_get_params+0x72f/0x780 net/nfc/netlink.c:1045 Read of size 8 at addr ffff888105b0e410 by task 20114 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x72/0xa0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:319 [inline] print_report+0xcc/0x620 mm/kasan/report.c:430 kasan_report+0xb2/0xe0 mm/kasan/report.c:536 nfc_genl_send_params net/nfc/netlink.c:999 [inline] nfc_genl_llc_get_params+0x72f/0x780 net/nfc/netlink.c:1045 genl_family_rcv_msg_doit.isra.0+0x1ee/0x2e0 net/netlink/genetlink.c:968 genl_family_rcv_msg net/netlink/genetlink.c:1048 [inline] genl_rcv_msg+0x503/0x7d0 net/netlink/genetlink.c:1065 netlink_rcv_skb+0x161/0x430 net/netlink/af_netlink.c:2548 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1076 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x644/0x900 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x934/0xe70 net/netlink/af_netlink.c:1913 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0x1b6/0x200 net/socket.c:747 ____sys_sendmsg+0x6e9/0x890 net/socket.c:2501 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2555 __sys_sendmsg+0xf7/0x1d0 net/socket.c:2584 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3f/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f34640a2389 RSP: 002b:00007f3463415168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f34641c1f80 RCX: 00007f34640a2389 RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000006 RBP: 00007f34640ed493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe38449ecf R14: 00007f3463415300 R15: 0000000000022000 Allocated by task 20116: kasan_save_stack+0x22/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x7f/0x90 mm/kasan/common.c:383 kmalloc include/linux/slab.h:580 [inline] kzalloc include/linux/slab.h:720 [inline] nfc_llcp_register_device+0x49/0xa40 net/nfc/llcp_core.c:1567 nfc_register_device+0x61/0x260 net/nfc/core.c:1124 nci_register_device+0x776/0xb20 net/nfc/nci/core.c:1257 virtual_ncidev_open+0x147/0x230 drivers/nfc/virtual_ncidev.c:148 misc_open+0x379/0x4a0 drivers/char/misc.c:165 chrdev_open+0x26c/0x780 fs/char_dev.c:414 do_dentry_open+0x6c4/0x12a0 fs/open.c:920 do_open fs/namei.c:3560 [inline] path_openat+0x24fe/0x37e0 fs/namei.c:3715 do_filp_open+0x1ba/0x410 fs/namei.c:3742 do_sys_openat2+0x171/0x4c0 fs/open.c:1356 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x143/0x200 fs/open.c:1383 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3f/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc Freed by task 20115: kasan_save_stack+0x22/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free mm/kasan/common.c:200 [inline] __kasan_slab_free+0x10a/0x190 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook mm/slub.c:1807 [inline] slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0x7a/0x190 mm/slub.c:3800 local_release net/nfc/llcp_core.c:174 [inline] kref_put include/linux/kref.h:65 [inline] nfc_llcp_local_put net/nfc/llcp_core.c:182 [inline] nfc_llcp_local_put net/nfc/llcp_core.c:177 [inline] nfc_llcp_unregister_device+0x206/0x290 net/nfc/llcp_core.c:1620 nfc_unregister_device+0x160/0x1d0 net/nfc/core.c:1179 virtual_ncidev_close+0x52/0xa0 drivers/nfc/virtual_ncidev.c:163 __fput+0x252/0xa20 fs/file_table.c:321 task_work_run+0x174/0x270 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x108/0x110 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x21/0x50 kernel/entry/common.c:297 do_syscall_64+0x4c/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x72/0xdc Last potentially related work creation: kasan_save_stack+0x22/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0x95/0xb0 mm/kasan/generic.c:491 kvfree_call_rcu+0x29/0xa80 kernel/rcu/tree.c:3328 drop_sysctl_table+0x3be/0x4e0 fs/proc/proc_sysctl.c:1735 unregister_sysctl_table.part.0+0x9c/0x190 fs/proc/proc_sysctl.c:1773 unregister_sysctl_table+0x24/0x30 fs/proc/proc_sysctl.c:1753 neigh_sysctl_unregister+0x5f/0x80 net/core/neighbour.c:3895 addrconf_notify+0x140/0x17b0 net/ipv6/addrconf.c:3684 notifier_call_chain+0xbe/0x210 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x150 net/core/dev.c:1937 call_netdevice_notifiers_extack net/core/dev.c:1975 [inline] call_netdevice_notifiers net/core/dev.c:1989 [inline] dev_change_name+0x3c3/0x870 net/core/dev.c:1211 dev_ifsioc+0x800/0xf70 net/core/dev_ioctl.c:376 dev_ioctl+0x3d9/0xf80 net/core/dev_ioctl.c:542 sock_do_ioctl+0x160/0x260 net/socket.c:1213 sock_ioctl+0x3f9/0x670 net/socket.c:1316 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x19e/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3f/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc The buggy address belongs to the object at ffff888105b0e400 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 16 bytes inside of freed 1024-byte region [ffff888105b0e400, ffff888105b0e800) The buggy address belongs to the physical page: head:ffffea000416c200 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x200000000010200(slab|head|node=0|zone=2) raw: 0200000000010200 ffff8881000430c0 ffffea00044c7010 ffffea0004510e10 raw: 0000000000000000 00000000000a000a 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888105b0e300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888105b0e380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888105b0e400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888105b0e480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888105b0e500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb In summary, this patch solves those use-after-free by 1. Re-implement the nfc_llcp_find_local(). The current version does not grab the reference when getting the local from the linked list. For example, the llcp_sock_bind() gets the reference like below: // llcp_sock_bind() local = nfc_llcp_find_local(dev); // A ..... \ | raceable ..... / llcp_sock->local = nfc_llcp_local_get(local); // B There is an apparent race window that one can drop the reference and free the local object fetched in (A) before (B) gets the reference. 2. Some callers of the nfc_llcp_find_local() do not grab the reference at all. For example, the nfc_genl_llc_{{get/set}_params/sdreq} functions. We add the nfc_llcp_local_put() for them. Moreover, we add the necessary error handling function to put the reference. 3. Add the nfc_llcp_remove_local() helper. The local object is removed from the linked list in local_release() when all reference is gone. This patch removes it when nfc_llcp_unregister_device() is called. Therefore, every caller of nfc_llcp_find_local() will get a reference even when the nfc_llcp_unregister_device() is called. This promises no use-after-free for the local object is ever possible. Fixes: 52feb444a903 ("NFC: Extend netlink interface for LTO, RW, and MIUX parameters support") Fixes: c7aa12252f51 ("NFC: Take a reference on the LLCP local pointer when creating a socket") Signed-off-by: Lin Ma Reviewed-by: Simon Horman Signed-off-by: David S. Miller

nfc: change order inside nfc_se_io error path

2023-03-07T21:37:05Z

cb_context should be freed on the error path in nfc_se_io as stated by commit 25ff6f8a5a3b ("nfc: fix memory leak of se_io context in nfc_genl_se_io"). Make the error path in nfc_se_io unwind everything in reverse order, i.e. free the cb_context after unlocking the device. Suggested-by: Krzysztof Kozlowski Signed-off-by: Fedor Pchelkin Reviewed-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20230306212650.230322-1-pchelkin@ispras.ru Signed-off-by: Jakub Kicinski

nfc: fix memory leak of se_io context in nfc_genl_se_io

2023-02-26T14:55:13Z

The callback context for sending/receiving APDUs to/from the selected secure element is allocated inside nfc_genl_se_io and supposed to be eventually freed in se_io_cb callback function. However, there are several error paths where the bwi_timer is not charged to call se_io_cb later, and the cb_context is leaked. The patch proposes to free the cb_context explicitly on those error paths. At the moment we can't simply check 'dev->ops->se_io()' return value as it may be negative in both cases: when the timer was charged and was not. Fixes: 5ce3f32b5264 ("NFC: netlink: SE API implementation") Reported-by: syzbot+df64c0a2e8d68e78a4fa@syzkaller.appspotmail.com Signed-off-by: Fedor Pchelkin Signed-off-by: Alexey Khoroshilov Signed-off-by: David S. Miller

nfc: Fix potential resource leaks

2022-12-26T09:09:23Z

nfc_get_device() take reference for the device, add missing nfc_put_device() to release it when not need anymore. Also fix the style warnning by use error EOPNOTSUPP instead of ENOTSUPP. Fixes: 5ce3f32b5264 ("NFC: netlink: SE API implementation") Fixes: 29e76924cf08 ("nfc: netlink: Add capability to reply to vendor_cmd with data") Signed-off-by: Miaoqian Lin Signed-off-by: David S. Miller

genetlink: start to validate reserved header bytes

2022-08-29T11:47:15Z

We had historically not checked that genlmsghdr.reserved is 0 on input which prevents us from using those precious bytes in the future. One use case would be to extend the cmd field, which is currently just 8 bits wide and 256 is not a lot of commands for some core families. To make sure that new families do the right thing by default put the onus of opting out of validation on existing families. Signed-off-by: Jakub Kicinski Acked-by: Paul Moore (NetLabel) Signed-off-by: David S. Miller

NFC: netlink: fix sleep in atomic bug when firmware download timeout

2022-05-05T08:18:15Z

There are sleep in atomic bug that could cause kernel panic during firmware download process. The root cause is that nlmsg_new with GFP_KERNEL parameter is called in fw_dnld_timeout which is a timer handler. The call trace is shown below: BUG: sleeping function called from invalid context at include/linux/sched/mm.h:265 Call Trace: kmem_cache_alloc_node __alloc_skb nfc_genl_fw_download_done call_timer_fn __run_timers.part.0 run_timer_softirq __do_softirq ... The nlmsg_new with GFP_KERNEL parameter may sleep during memory allocation process, and the timer handler is run as the result of a "software interrupt" that should not call any other function that could sleep. This patch changes allocation mode of netlink message from GFP_KERNEL to GFP_ATOMIC in order to prevent sleep in atomic bug. The GFP_ATOMIC flag makes memory allocation operation could be used in atomic context. Fixes: 9674da8759df ("NFC: Add firmware upload netlink command") Fixes: 9ea7187c53f6 ("NFC: netlink: Rename CMD_FW_UPLOAD to CMD_FW_DOWNLOAD") Signed-off-by: Duoming Zhou Reviewed-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20220504055847.38026-1-duoming@zju.edu.cn Signed-off-by: Paolo Abeni