9225d57f51
commit 9b024201693e397441668cca0d2df7055fe572eb upstream.
Change kstrtou32() argument 'base' to be zero instead of 'len'.
It works by chance for setting one bit value, but it is not supposed to
work in case value passed to mlxreg_io_attr_store() is greater than 1.
It works for example, for:
echo 1 > /sys/devices/platform/mlxplat/mlxreg-io/hwmon/.../jtag_enable
But it will fail for:
echo n > /sys/devices/platform/mlxplat/mlxreg-io/hwmon/.../jtag_enable,
where n > 1.
The flow for input buffer conversion is as below:
_kstrtoull(const char *s, unsigned int base, unsigned long long *res)
calls:
rv = _parse_integer(s, base, &_res);
For the second case, where n > 1:
- _parse_integer() converts 's' to 'val'.
For n=2, 'len' is set to 2 (string buffer is 0x32 0x0a), for n=3
'len' is set to 3 (string buffer 0x33 0x0a), etcetera.
- 'base' is equal or greater then '2' (length of input buffer).
As a result, _parse_integer() exits with result zero (rv):
rv = 0;
while (1) {
...
if (val >= base)-> (2 >= 2)
break;
...
rv++;
...
}
And _kstrtoull() in their turn will fail:
if (rv == 0)
return -EINVAL;
Fixes: 5ec4a8ace06c ("platform/mellanox: Introduce support for Mellanox register access driver")
Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Link: https://lore.kernel.org/r/20210927142214.2613929-2-vadimp@nvidia.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.