Re: Bug Report: Dereferencing a bad pointer

Brian Gerst (bgerst@didntduck.org)
Thu, 08 Nov 2001 17:39:02 -0500


David Chandler wrote:
>
> I get a seg fault on both 2.2 and 2.4 kernels by running the following
> one-line C program:
> int main() { int k = (int *)0x0; }
>
> Debugging the offender,
> int main() { int k = (int *)0xc0000000; }
> is not very informative: single-stepping over the sole command just
> hangs, and you have to press Control-C to interrupt gdb, at which point
> you can single-step right into the same problem again.
>
> When the program hangs, 'top' says that the CPU is fully utilized and
> the system is spending 80% of its time in the kernel and 20% in the
> offending process.
>
> Have you not been able to duplicate it on a 2.4 kernel on x86? If not,
> please tell me which 2.4 kernel correctly seg faults.

How about address 0xc0001000? I have been unable to reproduce this on a
PII running 2.4.9, and an Athlon running 2.4.14.

--

Brian Gerst - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/