On Thu, Nov 09, 2017 at 04:58:18PM +0530, Manjeet Pawar wrote:
> simple_strtoul() is obselete now, so using newer function kstrtoul()
>
> Signed-off-by: Manjeet Pawar <manjeet.p@xxxxxxxxxxx>
> Signed-off-by: Vinay Kumar Rijhwani <v.rijhwani@xxxxxxxxxxx>
> Signed-off-by: Rohit Thapliyal <r.thapliyal@xxxxxxxxxxx>
NAK NAK NAK.
You haven't tested this on a 64-bit big-endian machine.
> static int __init set_hashdist(char *str)
> {
> - if (!str)
> + if (!str || kstrtoul(str, 0, (unsigned long *)&hashdist))
> return 0;
> - hashdist = simple_strtoul(str, &str, 0);
> return 1;
The context missing from this patch is:
int hashdist = HASHDIST_DEFAULT;
So you're taking the address of an int and passing it to a function
which is expecting a pointer to an unsigned long. That works on a
32-bit machine because ints and longs are the same size. On a 64-bit
little-endian machine, the bits are in the right place, but kstrtoul()
will overwrite the 32 bits after the int with zeroes. On a 64-bit
big-endian machine, you'll overwrite the int that you're pointing to
with zeroes and the 32 bits after the int will have the data you're
looking for.
There's a kstrtoint(). Why would you not just use that?
Also, I'm shocked that this went through a chain of three different
sign-offs with nobody noticing the problem. Do none of you understand C?
(similar problems snipped).
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