diff options
| author | Muhammad Bilal <meatuni001@gmail.com> | 2026-07-28 17:54:55 +0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-09-01 12:15:16 +0200 |
| commit | ff917923f4fb9c83717ba135ee47d7e4c1567bb7 (patch) | |
| tree | c38fd8fcf58e1937b17fdbc6518b6f8b797fc15a /Documentation/driver-api/regulator.rst | |
| download | linux-stable-ff917923f4fb9c83717ba135ee47d7e4c1567bb7.tar.gz linux-stable-ff917923f4fb9c83717ba135ee47d7e4c1567bb7.zip | |
staging: rtl8723bs: fix OOB read in rtw_action_frame_parse()grafted
rtw_action_frame_parse() takes a frame_len parameter but never
actually checks it before indexing into the frame body:
const u8 *frame_body = frame + sizeof(struct ieee80211_hdr_3addr);
...
c = frame_body[0];
...
a = frame_body[1];
frame_body already points 24 bytes (sizeof(struct
ieee80211_hdr_3addr)) into frame, so reading frame_body[0] and
frame_body[1] requires frame_len >= 26. A management action frame
shorter than that (e.g. exactly 24 bytes, the minimum a malicious
peer can send) causes a 1-2 byte out-of-bounds read.
This is reachable from rtw_cfg80211_monitor_if_xmit_entry() and
cfg80211_rtw_mgmt_tx() in ioctl_cfg80211.c, both of which pass
attacker/user-influenced frame buffers and lengths straight through.
Add the missing length check before frame_body is dereferenced.
Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver")
Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/driver-api/regulator.rst')
| -rw-r--r-- | Documentation/driver-api/regulator.rst | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/Documentation/driver-api/regulator.rst b/Documentation/driver-api/regulator.rst new file mode 100644 index 000000000..b43c78eb2 --- /dev/null +++ b/Documentation/driver-api/regulator.rst @@ -0,0 +1,170 @@ +.. Copyright 2007-2008 Wolfson Microelectronics + +.. This documentation is free software; you can redistribute +.. it and/or modify it under the terms of the GNU General Public +.. License version 2 as published by the Free Software Foundation. + +================================= +Voltage and current regulator API +================================= + +:Author: Liam Girdwood +:Author: Mark Brown + +Introduction +============ + +This framework is designed to provide a standard kernel interface to +control voltage and current regulators. + +The intention is to allow systems to dynamically control regulator power +output in order to save power and prolong battery life. This applies to +both voltage regulators (where voltage output is controllable) and +current sinks (where current limit is controllable). + +Note that additional (and currently more complete) documentation is +available in the Linux kernel source under +``Documentation/power/regulator``. + +Glossary +-------- + +The regulator API uses a number of terms which may not be familiar: + +Regulator + + Electronic device that supplies power to other devices. Most regulators + can enable and disable their output and some can also control their + output voltage or current. + +Consumer + + Electronic device which consumes power provided by a regulator. These + may either be static, requiring only a fixed supply, or dynamic, + requiring active management of the regulator at runtime. + +Power Domain + + The electronic circuit supplied by a given regulator, including the + regulator and all consumer devices. The configuration of the regulator + is shared between all the components in the circuit. + +Power Management Integrated Circuit (PMIC) + + An IC which contains numerous regulators and often also other + subsystems. In an embedded system the primary PMIC is often equivalent + to a combination of the PSU and southbridge in a desktop system. + +Consumer driver interface +========================= + +This offers a similar API to the kernel clock framework. Consumer +drivers use `get <#API-regulator-get>`__ and +`put <#API-regulator-put>`__ operations to acquire and release +regulators. Functions are provided to `enable <#API-regulator-enable>`__ +and `disable <#API-regulator-disable>`__ the regulator and to get and +set the runtime parameters of the regulator. + +When requesting regulators consumers use symbolic names for their +supplies, such as "Vcc", which are mapped into actual regulator devices +by the machine interface. + +A stub version of this API is provided when the regulator framework is +not in use in order to minimise the need to use ifdefs. + +Enabling and disabling +---------------------- + +The regulator API provides reference counted enabling and disabling of +regulators. Consumer devices use the :c:func:`regulator_enable()` and +:c:func:`regulator_disable()` functions to enable and disable +regulators. Calls to the two functions must be balanced. + +Note that since multiple consumers may be using a regulator and machine +constraints may not allow the regulator to be disabled there is no +guarantee that calling :c:func:`regulator_disable()` will actually +cause the supply provided by the regulator to be disabled. Consumer +drivers should assume that the regulator may be enabled at all times. + +Configuration +------------- + +Some consumer devices may need to be able to dynamically configure their +supplies. For example, MMC drivers may need to select the correct +operating voltage for their cards. This may be done while the regulator +is enabled or disabled. + +The :c:func:`regulator_set_voltage()` and +:c:func:`regulator_set_current_limit()` functions provide the primary +interface for this. Both take ranges of voltages and currents, supporting +drivers that do not require a specific value (eg, CPU frequency scaling +normally permits the CPU to use a wider range of supply voltages at lower +frequencies but does not require that the supply voltage be lowered). Where +an exact value is required both minimum and maximum values should be +identical. + +Callbacks +--------- + +Callbacks may also be registered for events such as regulation failures. + +Regulator driver interface +========================== + +Drivers for regulator chips register the regulators with the regulator +core, providing operations structures to the core. A notifier interface +allows error conditions to be reported to the core. + +Registration should be triggered by explicit setup done by the platform, +supplying a struct regulator_init_data for the regulator +containing constraint and supply information. + +Machine interface +================= + +This interface provides a way to define how regulators are connected to +consumers on a given system and what the valid operating parameters are +for the system. + +Supplies +-------- + +Regulator supplies are specified using struct +:c:type:`regulator_consumer_supply`. This is done at driver registration +time as part of the machine constraints. + +Constraints +----------- + +As well as defining the connections the machine interface also provides +constraints defining the operations that clients are allowed to perform +and the parameters that may be set. This is required since generally +regulator devices will offer more flexibility than it is safe to use on +a given system, for example supporting higher supply voltages than the +consumers are rated for. + +This is done at driver registration time` by providing a +struct regulation_constraints. + +The constraints may also specify an initial configuration for the +regulator in the constraints, which is particularly useful for use with +static consumers. + +API reference +============= + +Due to limitations of the kernel documentation framework and the +existing layout of the source code the entire regulator API is +documented here. + +.. kernel-doc:: include/linux/regulator/consumer.h + :internal: + +.. kernel-doc:: include/linux/regulator/machine.h + :internal: + +.. kernel-doc:: include/linux/regulator/driver.h + :internal: + +.. kernel-doc:: drivers/regulator/core.c + :export: |
