The I2C_SMBUS_I2C_BLOCK_DATA case in stub_xfer() uses data->block[0]
as the transfer length. The existing check only clamps it to avoid
overrunning the chip->words[256] register array, but does not validate
it against I2C_SMBUS_BLOCK_MAX (32), which is the limit of the union
i2c_smbus_data.block buffer (34 bytes total). The driver is a
development/test tool (CONFIG_I2C_STUB=m, not built by default)
that must be loaded with a chip_addr= parameter.
A local user with access to /dev/i2c-* can issue an I2C_SMBUS ioctl
with I2C_SMBUS_I2C_BLOCK_DATA and data->block[0] > 32, causing
stub_xfer() to read or write past the end of the union
i2c_smbus_data.block buffer:
BUG: KASAN: stack-out-of-bounds in stub_xfer (drivers/i2c/i2c-stub.c:223)
Read of size 1 at addr ffff88800abcfd92 by task exploit/81
Call Trace:
<TASK>
stub_xfer (drivers/i2c/i2c-stub.c:223)
__i2c_smbus_xfer (drivers/i2c/i2c-core-smbus.c:593)
i2c_smbus_xfer (drivers/i2c/i2c-core-smbus.c:536)
i2cdev_ioctl_smbus (drivers/i2c/i2c-dev.c:391)
i2cdev_ioctl (drivers/i2c/i2c-dev.c:478)
__x64_sys_ioctl (fs/ioctl.c:583)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
</TASK>
The bug exists because i2c-stub implements .smbus_xfer directly,
bypassing the I2C_SMBUS_BLOCK_MAX validation in
i2c_smbus_xfer_emulated(). The I2C_SMBUS_BLOCK_DATA case in the same
function correctly validates against I2C_SMBUS_BLOCK_MAX, but the
I2C_SMBUS_I2C_BLOCK_DATA case does not.
Fix by rejecting transfers with data->block[0] == 0 or
data->block[0] > I2C_SMBUS_BLOCK_MAX with -EINVAL, consistent with
both the I2C_SMBUS_BLOCK_DATA case in the same function and the
I2C_SMBUS_I2C_BLOCK_DATA validation in i2c_smbus_xfer_emulated().
Fixes: 4710317891 ("i2c-stub: Implement I2C block support")
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <kees@kernel.org>
After removal of the legacy eeprom driver the only remaining I2C
client device driver supporting I2C_CLASS_SPD is jc42. Because this
driver also supports I2C_CLASS_HWMON, adapters don't have to
declare support for I2C_CLASS_SPD if they support I2C_CLASS_HWMON.
It's one step towards getting rid of I2C_CLASS_SPD mid-term.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Defining DEBUG should only be done in development.
So remove DEBUG.
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Based on 3 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1105 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 6c42778780 ("i2c: stub: use pr_fmt") changed the DEBUG
handling and caused build warnings. Revert back to the original.
Fixes: 6c42778780 ("i2c: stub: use pr_fmt")
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Instead of hard coding "i2c-stub:", let's use the pr_fmt mechanism to
achieve the same more easily. This makes it easier to stay consistent
when adding new messages. Also, remove an unneeded OOM message while we
are here.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I2C block transfers can have a size up to 32 bytes. If starting close
to the end of the address space, there may not be enough room to write
that many bytes (on I2C block writes) or not enough bytes to be read
(on I2C block reads.) In that case, we must shorten the transfer so
that it does not exceed the address space.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Some chips implement banked register ranges. This allows implementing
more registers than the limited 8-bit address space originally allows.
In order to access a register on these chips, you must first select
the proper bank. Add support for this mechanism to the i2c-stub driver
so that such chips can be emulated. All the bank settings are passed
as module parameters.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This makes initialization, cleanup and look-up easier.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
SMBus block commands are different to I2C block commands since
the returned data is not normally accessible with byte or word
commands on other command offsets. Add linked list of 'block'
commands to support those commands.
Access mechanism is quite simple: Block commands must be written
before they can be read. Subsequent writes can be partial. Block
read commands always return the number of bytes associated with
the longest previous write.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Move the i2c-stub driver to drivers/i2c, to match the Kconfig entry.
This is less confusing that way.
I also fixed all checkpatch warnings and errors.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Peter Huewe <peterhuewe@gmx.de>
