From 4310c6b8e75d6a47f7548e5948fbe6318aa4440a Mon Sep 17 00:00:00 2001 From: Fedor Pchelkin Date: Mon, 31 Aug 2026 10:58:09 +0300 Subject: thunderbolt: Fix NULL dereference in tb_remove_work() There is a slight race between tb_remove_work() and tb_domain_remove() which leads to dereferencing a NULL tb->root_switch pointer inside tb_free_unplugged_xdomains(): Thread A Thread B tb_remove_work() tb_domain_remove() mutex_lock(&tb->lock) tb_stop() /* doesn't cancel a running callback */ cancel_delayed_work(&tcm->remove_work) ... tb_switch_remove(tb->root_switch) tb->root_switch = NULL mutex_unlock(&tb->lock) mutex_lock(&tb->lock) ... /* without checking ->root_switch */ tb_free_unplugged_xdomains(tb->root_switch) mutex_unlock(&tb->lock) Commit a8937f35cf39 ("thunderbolt: Remove XDomain from the bus without holding tb->lock") doesn't seem right to move tb_free_unplugged_xdomains() out of the &tb->lock section and the check for tb->root_switch, in particular. It states: For this reason separate removing the XDomain from the topology data structures (where we need the lock) from unregistering the device from the bus (where remove callbacks of the drivers are being called). tb_free_unplugged_xdomains() belongs to the former group of functions requiring the lock. And it also calls tb_xdomain_remove() which should only be called with &tb->lock held. Found by Linux Verification Center (linuxtesting.org) with Svace static analysis tool. Fixes: a8937f35cf39 ("thunderbolt: Remove XDomain from the bus without holding tb->lock") Cc: stable@vger.kernel.org Signed-off-by: Fedor Pchelkin Signed-off-by: Mika Westerberg --- include/clocksource/timer-davinci.h | 44 +++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 include/clocksource/timer-davinci.h (limited to 'include/clocksource/timer-davinci.h') diff --git a/include/clocksource/timer-davinci.h b/include/clocksource/timer-davinci.h new file mode 100644 index 000000000..1dcc1333f --- /dev/null +++ b/include/clocksource/timer-davinci.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * TI DaVinci clocksource driver + * + * Copyright (C) 2019 Texas Instruments + * Author: Bartosz Golaszewski + */ + +#ifndef __TIMER_DAVINCI_H__ +#define __TIMER_DAVINCI_H__ + +#include +#include + +enum { + DAVINCI_TIMER_CLOCKEVENT_IRQ, + DAVINCI_TIMER_CLOCKSOURCE_IRQ, + DAVINCI_TIMER_NUM_IRQS, +}; + +/** + * struct davinci_timer_cfg - davinci clocksource driver configuration struct + * @reg: register range resource + * @irq: clockevent and clocksource interrupt resources + * @cmp_off: if set - it specifies the compare register used for clockevent + * + * Note: if the compare register is specified, the driver will use the bottom + * clock half for both clocksource and clockevent and the compare register + * to generate event irqs. The user must supply the correct compare register + * interrupt number. + * + * This is only used by da830 the DSP of which uses the top half. The timer + * driver still configures the top half to run in free-run mode. + */ +struct davinci_timer_cfg { + struct resource reg; + struct resource irq[DAVINCI_TIMER_NUM_IRQS]; + unsigned int cmp_off; +}; + +int __init davinci_timer_register(struct clk *clk, + const struct davinci_timer_cfg *data); + +#endif /* __TIMER_DAVINCI_H__ */ -- cgit v1.3.1