[Crash-utility] [PATCH] Fix unsigned signed comparison causing segfault for small VMCOREINFO notes

[Dave Anderson]

----- Original Message -----
> Hi,
> 
> This is a fix for a signed/unsigned comparison bug in vmcoreinfo_read_string.
> The bug causes a segmentation fault if size_vmcoreinfo + 1 is smaller than
> the length of the key string passed in.

I suppose that's true, but can you describe the instance where that actually happened?
Can you show the actual note contents as shown by "help -D"?

Thanks,
  Dave


> 
> Signed-off-by: Nuno Das Neves <nudasnev at microsoft.com>
> ---
>  netdump.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/netdump.c b/netdump.c
> index 40f9cde..d257ecd 100644
> --- a/netdump.c
> +++ b/netdump.c
> @@ -1838,7 +1838,7 @@ vmcoreinfo_read_string(const char *key)
>  		return NULL;
>  
>  	/* the '+ 1' is the equal sign */
> -	for (i = 0; i < (size_vmcoreinfo - key_length + 1); i++) {
> +	for (i = 0; i < (int)(size_vmcoreinfo - key_length + 1); i++) {
>  		/*
>  		 * We must also check if we're at the beginning of VMCOREINFO
>  		 * or the separating newline is there, and of course if we
> --
> 1.8.3.1
> 
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