Commit effa453168 ("i2c: i801: Don't silently correct invalid transfer
size") revealed that ee1004_eeprom_read() did not properly limit how
many bytes to read at once.
In particular, i2c_smbus_read_i2c_block_data_or_emulated() takes the
length to read as an u8. If count == 256 after taking into account the
offset and page boundary, the cast to u8 overflows. And this is common
when user space tries to read the entire EEPROM at once.
To fix it, limit each read to I2C_SMBUS_BLOCK_MAX (32) bytes, already
the maximum length i2c_smbus_read_i2c_block_data_or_emulated() allows.
Fixes: effa453168 ("i2c: i801: Don't silently correct invalid transfer size")
Cc: stable@vger.kernel.org
Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Jonas Malaco <jonas@protocubo.io>
Link: https://lore.kernel.org/r/20220203165024.47767-1-jonas@protocubo.io
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Moving the call to ee1004_set_current_page() to ee1004_eeprom_read()
allows to simplify the code.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/2829a131-51e3-8865-462a-564080158b0b@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The value of ee1004_current_page applies to all SPD eeproms connected
to the adapter. Therefore it's sufficient if we set ee1004_current_page
when the first device is added.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/b9240e58-08bb-3d71-7a9c-9a323b470ab6@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
i2c_new_dummy_device() calls i2c_new_client_device() that complains
if it fails to create the device. Therefore we don't have to emit an
error message in case of failure. In addition ensure that
ee1004_set_page is only set if creating the device succeeded.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/d38df5ac-6ecb-7d5f-b5c3-39bfc6a1e8a1@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We have to read 512 bytes only, therefore read performance isn't really
a concern. Don't bother the user if i2c block read isn't supported.
For i2c_smbus_read_i2c_block_data_or_emulated() to work it's sufficient
if I2C_FUNC_SMBUS_READ_I2C_BLOCK or I2C_FUNC_SMBUS_READ_BYTE_DATA is
supported. Therefore remove the check for I2C_FUNC_SMBUS_READ_WORD_DATA.
In addition check for I2C_FUNC_SMBUS_WRITE_BYTE (included in
I2C_FUNC_SMBUS_BYTE) which is needed for setting the page.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/840c668e-6310-e933-e50e-5abeaecfb39c@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
i2c_smbus_read_i2c_block_data_or_emulated() checks its length argument,
so we don't have to do it. In addition remove the unlikely hint from
the checks, we do i2c reads and therefore are in a slow path.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/eb2a8bff-43ec-c763-a417-9d741e6f0034@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sysfs_kf_bin_read() checks this for us already. In addition
the function works correctly also w/o this check.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/33889bff-3614-4b73-5010-701635e1edab@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Instead of creating/removing the attribute ourselves, just declare the
attribute and let the device core handle it. This allows to simplify
the code.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/8a6c77f2-f84a-311b-c2b9-21798f690e4d@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move from i2c_new_dummy() to i2c_new_dummy_device(), so we now get an
ERRPTR which we use in error handling.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20190722172616.3982-2-wsa+renesas@sang-engineering.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 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
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some EE1004 implementations will not properly ack page selection
commands. They still set the page correctly, so there is no actual
error. Deal with this case gracefully by checking the currently
selected page after we receive a nack. If the page is set right then
we can continue.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
No functional change, this is in preparation for future needs.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The EEPROMs which hold the SPD data on DDR4 memory modules are no
longer standard AT24C02-compatible EEPROMs. They are 512-byte EEPROMs
which use only 1 I2C address for data access. You need to switch
between the lower page and the upper page of data by sending commands
on the SMBus.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Jonas Malaco