From 3f1fe48a36b0b6722dc3fd421d93512bac138e9a Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 2 Oct 2026 12:17:24 -0700 Subject: Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters --- samples/livepatch/livepatch-sample.c | 71 ++++++++++++++++++++++++++++++++++++ 1 file changed, 71 insertions(+) create mode 100644 samples/livepatch/livepatch-sample.c (limited to 'samples/livepatch/livepatch-sample.c') diff --git a/samples/livepatch/livepatch-sample.c b/samples/livepatch/livepatch-sample.c new file mode 100644 index 000000000..5263a2f31 --- /dev/null +++ b/samples/livepatch/livepatch-sample.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * livepatch-sample.c - Kernel Live Patching Sample Module + * + * Copyright (C) 2014 Seth Jennings + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include + +/* + * This (dumb) live patch overrides the function that prints the + * kernel boot cmdline when /proc/cmdline is read. + * + * Example: + * + * $ cat /proc/cmdline + * + * + * $ insmod livepatch-sample.ko + * $ cat /proc/cmdline + * this has been live patched + * + * $ echo 0 > /sys/kernel/livepatch/livepatch_sample/enabled + * $ cat /proc/cmdline + * + */ + +#include +static int livepatch_cmdline_proc_show(struct seq_file *m, void *v) +{ + seq_printf(m, "%s\n", "this has been live patched"); + return 0; +} + +static struct klp_func funcs[] = { + { + .old_name = "cmdline_proc_show", + .new_func = livepatch_cmdline_proc_show, + }, { } +}; + +static struct klp_object objs[] = { + { + /* name being NULL means vmlinux */ + .funcs = funcs, + }, { } +}; + +static struct klp_patch patch = { + .mod = THIS_MODULE, + .objs = objs, +}; + +static int livepatch_init(void) +{ + return klp_enable_patch(&patch); +} + +static void livepatch_exit(void) +{ +} + +module_init(livepatch_init); +module_exit(livepatch_exit); +MODULE_DESCRIPTION("Kernel Live Patching Sample Module"); +MODULE_LICENSE("GPL"); +MODULE_INFO(livepatch, "Y"); -- cgit v1.3.1