kernel/linux.git/drivers/nfc/pn533/uart.c, branch v7.0.10

nfc: pn533: allocate rx skb before consuming bytes

2026-04-09T11:54:37+00:00

pn532_receive_buf() reports the number of accepted bytes to the serdev core. The current code consumes bytes into recv_skb and may already hand a complete frame to pn533_recv_frame() before allocating a fresh receive buffer. If that alloc_skb() fails, the callback returns 0 even though it has already consumed bytes, and it leaves recv_skb as NULL for the next receive callback. That breaks the receive_buf() accounting contract and can also lead to a NULL dereference on the next skb_put_u8(). Allocate the receive skb lazily before consuming the next byte instead. If allocation fails, return the number of bytes already accepted. Fixes: c656aa4c27b1 ("nfc: pn533: add UART phy driver") Cc: stable@vger.kernel.org Signed-off-by: Pengpeng Hou Link: https://patch.msgid.link/20260405094003.3-pn533-v2-pengpeng@iscas.ac.cn Signed-off-by: Paolo Abeni

NFC: pn533: bound the UART receive buffer

2026-03-31T09:04:30+00:00

pn532_receive_buf() appends every incoming byte to dev->recv_skb and only resets the buffer after pn532_uart_rx_is_frame() recognizes a complete frame. A continuous stream of bytes without a valid PN532 frame header therefore keeps growing the skb until skb_put_u8() hits the tail limit. Drop the accumulated partial frame once the fixed receive buffer is full so malformed UART traffic cannot grow the skb past PN532_UART_SKB_BUFF_LEN. Fixes: c656aa4c27b1 ("nfc: pn533: add UART phy driver") Signed-off-by: Pengpeng Hou Link: https://patch.msgid.link/20260326142033.82297-1-pengpeng@iscas.ac.cn Signed-off-by: Paolo Abeni

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

treewide, timers: Rename from_timer() to timer_container_of()

2025-06-08T07:07:37+00:00

Move this API to the canonical timer_*() namespace. [ tglx: Redone against pre rc1 ] Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12+00:00

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar

treewide, serdev: change receive_buf() return type to size_t

2024-01-28T02:13:53+00:00

receive_buf() is called from ttyport_receive_buf() that expects values ">= 0" from serdev_controller_receive_buf(), change its return type from ssize_t to size_t. The need for this clean-up was noticed while fixing a warning, see commit 94d053942544 ("Bluetooth: btnxpuart: fix recv_buf() return value"). Changing the callback prototype to return an unsigned seems the best way to document the API and ensure that is properly used. GNSS drivers implementation of serdev receive_buf() callback return directly the return value of gnss_insert_raw(). gnss_insert_raw() returns a signed int, however this is not an issue since the value returned is always positive, because of the kfifo_in() implementation. gnss_insert_raw() could be changed to return also an unsigned, however this is not implemented here as request by the GNSS maintainer Johan Hovold. Suggested-by: Jiri Slaby Link: https://lore.kernel.org/all/087be419-ec6b-47ad-851a-5e1e3ea5cfcc@kernel.org/ Signed-off-by: Francesco Dolcini Acked-by: Jonathan Cameron #for-iio Reviewed-by: Johan Hovold Reviewed-by: Rob Herring Reviewed-by: Alex Elder Acked-by: Maximilian Luz # for platform/surface Acked-by: Lee Jones Acked-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20240122180551.34429-1-francesco@dolcini.it Signed-off-by: Greg Kroah-Hartman

tty: serdev: convert to u8 and size_t

2023-12-08T11:02:38+00:00

Switch character types to u8 and sizes to size_t. To conform to characters/sizes in the rest of the tty layer. This patch converts struct serdev_device_ops hooks and its instantiations. Signed-off-by: "Jiri Slaby (SUSE)" Cc: Rob Herring Acked-by: Johan Hovold Link: https://lore.kernel.org/r/20231206073712.17776-24-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

treewide: Convert del_timer() to timer_shutdown()

2022-12-25T21:38:09+00:00

Due to several bugs caused by timers being re-armed after they are shutdown and just before they are freed, a new state of timers was added called "shutdown". After a timer is set to this state, then it can no longer be re-armed. The following script was run to find all the trivial locations where del_timer() or del_timer_sync() is called in the same function that the object holding the timer is freed. It also ignores any locations where the timer->function is modified between the del_timer*() and the free(), as that is not considered a "trivial" case. This was created by using a coccinelle script and the following commands: $ cat timer.cocci @@ expression ptr, slab; identifier timer, rfield; @@ ( - del_timer(&ptr->timer); + timer_shutdown(&ptr->timer); | - del_timer_sync(&ptr->timer); + timer_shutdown_sync(&ptr->timer); ) ... when strict when != ptr->timer ( kfree_rcu(ptr, rfield); | kmem_cache_free(slab, ptr); | kfree(ptr); ) $ spatch timer.cocci . > /tmp/t.patch $ patch -p1 < /tmp/t.patch Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/ Signed-off-by: Steven Rostedt (Google) Acked-by: Pavel Machek [ LED ] Acked-by: Kalle Valo [ wireless ] Acked-by: Paolo Abeni [ networking ] Signed-off-by: Linus Torvalds

nfc: pn533: Fix use-after-free bugs caused by pn532_cmd_timeout

2022-08-22T13:51:30+00:00

When the pn532 uart device is detaching, the pn532_uart_remove() is called. But there are no functions in pn532_uart_remove() that could delete the cmd_timeout timer, which will cause use-after-free bugs. The process is shown below: (thread 1) | (thread 2) | pn532_uart_send_frame pn532_uart_remove | mod_timer(&pn532->cmd_timeout,...) ... | (wait a time) kfree(pn532) //FREE | pn532_cmd_timeout | pn532_uart_send_frame | pn532->... //USE This patch adds del_timer_sync() in pn532_uart_remove() in order to prevent the use-after-free bugs. What's more, the pn53x_unregister_nfc() is well synchronized, it sets nfc_dev->shutting_down to true and there are no syscalls could restart the cmd_timeout timer. Fixes: c656aa4c27b1 ("nfc: pn533: add UART phy driver") Signed-off-by: Duoming Zhou Signed-off-by: David S. Miller