Michael Holzheu wrote:
> Hi Dave,
>
> Here comes a fix for the bt -f command.
>
> The problem is that when the backchain is invalid on s390(x) we can get huge values for the stackframe size. This can lead to a termination of crash with a SIGSEGV. To fix this, we have to use in case of an invalid backchain the difference between the current backchain and the end of the stack as stackframe size.
>
> ---
>
Thanks Michael -- queued for the next release.
Dave
>
> diff -Naur crash-4.0-2.31/s390.c crash-4.0-2.31-s390-bt-f.fix/s390.c
> --- crash-4.0-2.31/s390.c 2006-06-27 16:15:32.000000000 +0200
> +++ crash-4.0-2.31-s390-bt-f.fix/s390.c 2006-07-03 16:37:34.000000000 +0200
> @@ -714,7 +714,9 @@
> frame_size = stack_base - old_backchain
> + KERNEL_STACK_SIZE;
> } else {
> - frame_size = backchain - old_backchain;
> + frame_size = MIN((backchain - old_backchain),
> + (stack_base - old_backchain +
> + KERNEL_STACK_SIZE));
> }
> for(j=0; j< frame_size; j+=4){
> if(j % 16 == 0){
> diff -Naur crash-4.0-2.31/s390x.c crash-4.0-2.31-s390-bt-f.fix/s390x.c
> --- crash-4.0-2.31/s390x.c 2006-06-27 16:15:32.000000000 +0200
> +++ crash-4.0-2.31-s390-bt-f.fix/s390x.c 2006-07-03 16:37:37.000000000 +0200
> @@ -747,7 +747,9 @@
> frame_size = stack_base - old_backchain
> + KERNEL_STACK_SIZE;
> } else {
> - frame_size = backchain - old_backchain;
> + frame_size = MIN((backchain - old_backchain),
> + (stack_base - old_backchain +
> + KERNEL_STACK_SIZE));
> }
> for(j=0; j< frame_size; j+=4){
> if(j % 16 == 0){
