linux-kernel - Re:[PATCH v6] ACPI: battery: prevent sysfs_add

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250923161354.1307251-1-luogf2025@163.com>
Date: Wed, 24 Sep 2025 00:13:54 +0800
From: GuangFei Luo <luogf2025@....com>
To: rafael@...nel.org
Cc: michal.wilczynski@...el.com,
	dan.carpenter@...aro.org,
	lenb@...nel.org,
	linux-acpi@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-pm@...r.kernel.org,
	lkp@...el.com,
	sre@...nel.org,
	stable@...r.kernel.org
Subject: Re:[PATCH v6] ACPI: battery: prevent sysfs_add_battery re-entry on rapid events

The functions battery_hook_add_battery(), battery_hook_remove_battery(),
and sysfs_remove_battery() already acquire locks, so their internal
accesses are safe.

acpi_battery_refresh() does check battery->bat, but its child
functions (sysfs_add_battery() and sysfs_remove_battery()) already
handle locking.

In acpi_battery_notify(), battery->bat has no lock. However, the
check of battery->bat is at the very end of the function. During
earlier calls, battery->bat has already been protected by locks, so
re-entry will not cause issues.