kernel/linux.git/include/net/nfc/nci_core.h, branch linux-7.0.y

net: nfc: nci: Increase NCI_DATA_TIMEOUT to 3000 ms

2025-09-04T00:02:12+00:00

An exchange with a NFC target must complete within NCI_DATA_TIMEOUT. A delay of 700 ms is not sufficient for cryptographic operations on smart cards. CardOS 6.0 may need up to 1.3 seconds to perform 256-bit ECDH or 3072-bit RSA. To prevent brute-force attacks, passports and similar documents introduce even longer delays into access control protocols (BAC/PACE). The timeout should be higher, but not too much. The expiration allows us to detect that a NFC target has disappeared. Signed-off-by: Juraj Šarinay Reviewed-by: Krzysztof Kozlowski Link: https://patch.msgid.link/20250902113630.62393-1-juraj@sarinay.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: add NCI_UNREG flag to eliminate the race

2021-11-18T04:17:05+00:00

There are two sites that calls queue_work() after the destroy_workqueue() and lead to possible UAF. The first site is nci_send_cmd(), which can happen after the nci_close_device as below nfcmrvl_nci_unregister_dev | nfc_genl_dev_up nci_close_device | flush_workqueue | del_timer_sync | nci_unregister_device | nfc_get_device destroy_workqueue | nfc_dev_up nfc_unregister_device | nci_dev_up device_del | nci_open_device | __nci_request | nci_send_cmd | queue_work !!! Another site is nci_cmd_timer, awaked by the nci_cmd_work from the nci_send_cmd. ... | ... nci_unregister_device | queue_work destroy_workqueue | nfc_unregister_device | ... device_del | nci_cmd_work | mod_timer | ... | nci_cmd_timer | queue_work !!! For the above two UAF, the root cause is that the nfc_dev_up can race between the nci_unregister_device routine. Therefore, this patch introduce NCI_UNREG flag to easily eliminate the possible race. In addition, the mutex_lock in nci_close_device can act as a barrier. Signed-off-by: Lin Ma Fixes: 6a2968aaf50c ("NFC: basic NCI protocol implementation") Reviewed-by: Jakub Kicinski Reviewed-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20211116152732.19238-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski

nfc: hci: pass callback data param as pointer in nci_request()

2021-08-02T14:11:37+00:00

The nci_request() receives a callback function and unsigned long data argument "opt" which is passed to the callback. Almost all of the nci_request() callers pass pointer to a stack variable as data argument. Only few pass scalar value (e.g. u8). All such callbacks do not modify passed data argument and in previous commit they were made as const. However passing pointers via unsigned long removes the const annotation. The callback could simply cast unsigned long to a pointer to writeable memory. Use "const void *" as type of this "opt" argument to solve this and prevent modifying the pointed contents. This is also consistent with generic pattern of passing data arguments - via "void *". In few places which pass scalar values, use casts via "unsigned long" to suppress any warnings. Signed-off-by: Krzysztof Kozlowski Signed-off-by: David S. Miller

nfc: nci: constify several pointers to u8, sk_buff and other structs

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

Several functions receive pointers to u8, sk_buff or other structs 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. This makes const also data passed as "unsigned long opt" argument to nci_request() function. Usual flow for such functions is: 1. Receive "u8 *" and store it (the pointer) in a structure allocated on stack (e.g. struct nci_set_config_param), 2. Call nci_request() or __nci_request() passing a callback function an the pointer to the structure via an "unsigned long opt", 3. nci_request() calls the callback which dereferences "unsigned long opt" in a read-only way. This converts all above paths to use proper pointer to const data, so entire flow is safer. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Jakub Kicinski

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: constify nci_driver_ops (prop_ops and core_ops)

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

Neither the core nor the drivers modify the passed pointer to struct nci_driver_ops (consisting of function pointers), so make it a pointer to const for correctness and safety. Signed-off-by: Krzysztof Kozlowski Signed-off-by: David S. Miller

nfc: constify nci_ops

2021-07-25T08:21:20+00:00

The struct nci_ops is modified by NFC core in only one case: nci_allocate_device() receives too many proprietary commands (prop_ops) to configure. This is a build time known constrain, so a graceful handling of such case is not necessary. Instead, fail the nci_allocate_device() and add BUILD_BUG_ON() to places which set these. This allows to constify the struct nci_ops (consisting of function pointers) for correctness and safety. Signed-off-by: Krzysztof Kozlowski Signed-off-by: David S. Miller

nfc: constify payload argument in nci_send_cmd()

2021-07-25T08:21:20+00:00

The nci_send_cmd() payload argument is passed directly to skb_put_data() which already accepts a pointer to const, so make it const as well for correctness and safety. Signed-off-by: Krzysztof Kozlowski Signed-off-by: David S. Miller

NFC: nci: fix memory leak in nci_allocate_device

2021-05-17T20:56:29+00:00

nfcmrvl_disconnect fails to free the hci_dev field in struct nci_dev. Fix this by freeing hci_dev in nci_free_device. BUG: memory leak unreferenced object 0xffff888111ea6800 (size 1024): comm "kworker/1:0", pid 19, jiffies 4294942308 (age 13.580s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 60 fd 0c 81 88 ff ff .........`...... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000004bc25d43>] kmalloc include/linux/slab.h:552 [inline] [<000000004bc25d43>] kzalloc include/linux/slab.h:682 [inline] [<000000004bc25d43>] nci_hci_allocate+0x21/0xd0 net/nfc/nci/hci.c:784 [<00000000c59cff92>] nci_allocate_device net/nfc/nci/core.c:1170 [inline] [<00000000c59cff92>] nci_allocate_device+0x10b/0x160 net/nfc/nci/core.c:1132 [<00000000006e0a8e>] nfcmrvl_nci_register_dev+0x10a/0x1c0 drivers/nfc/nfcmrvl/main.c:153 [<000000004da1b57e>] nfcmrvl_probe+0x223/0x290 drivers/nfc/nfcmrvl/usb.c:345 [<00000000d506aed9>] usb_probe_interface+0x177/0x370 drivers/usb/core/driver.c:396 [<00000000bc632c92>] really_probe+0x159/0x4a0 drivers/base/dd.c:554 [<00000000f5009125>] driver_probe_device+0x84/0x100 drivers/base/dd.c:740 [<000000000ce658ca>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:846 [<000000007067d05f>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:431 [<00000000f8e13372>] __device_attach+0x122/0x250 drivers/base/dd.c:914 [<000000009cf68860>] bus_probe_device+0xc6/0xe0 drivers/base/bus.c:491 [<00000000359c965a>] device_add+0x5be/0xc30 drivers/base/core.c:3109 [<00000000086e4bd3>] usb_set_configuration+0x9d9/0xb90 drivers/usb/core/message.c:2164 [<00000000ca036872>] usb_generic_driver_probe+0x8c/0xc0 drivers/usb/core/generic.c:238 [<00000000d40d36f6>] usb_probe_device+0x5c/0x140 drivers/usb/core/driver.c:293 [<00000000bc632c92>] really_probe+0x159/0x4a0 drivers/base/dd.c:554 Reported-by: syzbot+19bcfc64a8df1318d1c3@syzkaller.appspotmail.com Fixes: 11f54f228643 ("NFC: nci: Add HCI over NCI protocol support") Signed-off-by: Dongliang Mu Signed-off-by: David S. Miller