Re: [dmidecode] [PATCH] dmioem: Fix segmentation fault in dmi_hp_240_attr()

[Jerry Hoemann]

On Thu, Aug 04, 2022 at 11:54:33AM +0200, Jean Delvare wrote:
> pr_attr() does not accept a NULL format string. glibc can deal with
> it, but FreeBSD's libc chokes on it.
> 
> Display the attributes as a list instead. Introduce pr_list_item_val()
> to display list items with a value. This is currently implemented
> exactly the same as pr_subattr(), but as the semantics are different,
> I prefer to make it a separate function.
> 
> Bug reported by Scott Benesh (Microchip).
> 
> Signed-off-by: Jean Delvare <jdelvare@suse.de>
> Fixes: a4b31b2bc537 ("dmioem: Present HPE type 240 attributes in a nicer way")
> Cc: Jerry Hoemann <jerry.hoemann@hpe.com>

Tested-by: Jerry Hoemann <jerry.hoemann@hpe.com>

Did you consider adding a check that format is nonzero to pr_attr()
like pr_list_start() does?

Thanks

Jerry

> ---
>  dmioem.c    |    5 +++--
>  dmioutput.c |   12 ++++++++++++
>  dmioutput.h |    1 +
>  3 files changed, 16 insertions(+), 2 deletions(-)
> 
> --- dmidecode.orig/dmioem.c   2022-08-04 11:01:11.827321223 +0200
> +++ dmidecode/dmioem.c        2022-08-04 11:48:36.927172122 +0200
> @@ -198,13 +198,14 @@ static void dmi_hp_240_attr(u64 defined,
>       };
>       unsigned int i;
>  
> -     pr_attr("Attributes Defined/Set", NULL);
> +     pr_list_start("Attributes Defined/Set", NULL);
>       for (i = 0; i < ARRAY_SIZE(attributes); i++)
>       {
>               if (!(defined.l & (1UL << i)))
>                       continue;
> -             pr_subattr(attributes[i], "%s", set.l & (1UL << i) ? "Yes" : 
> "No");
> +             pr_list_item_val(attributes[i], "%s", set.l & (1UL << i) ? 
> "Yes" : "No");
>       }
> +     pr_list_end();
>  }
>  
>  static void dmi_hp_203_assoc_hndl(const char *fname, u16 num)
> --- dmidecode.orig/dmioutput.c        2020-10-14 14:15:45.962471307 +0200
> +++ dmidecode/dmioutput.c     2022-08-04 11:42:11.397632448 +0200
> @@ -114,6 +114,18 @@ void pr_list_item(const char *format, ..
>       printf("\n");
>  }
>  
> +void pr_list_item_val(const char *name, const char *format, ...)
> +{
> +     va_list args;
> +
> +     printf("\t\t%s: ", name);
> +
> +     va_start(args, format);
> +     vprintf(format, args);
> +     va_end(args);
> +     printf("\n");
> +}
> +
>  void pr_list_end(void)
>  {
>       /* a no-op for text output */
> --- dmidecode.orig/dmioutput.h        2020-10-14 14:15:45.962471307 +0200
> +++ dmidecode/dmioutput.h     2022-08-04 11:40:19.178019967 +0200
> @@ -29,6 +29,7 @@ void pr_attr(const char *name, const cha
>  void pr_subattr(const char *name, const char *format, ...);
>  void pr_list_start(const char *name, const char *format, ...);
>  void pr_list_item(const char *format, ...);
> +void pr_list_item_val(const char *name, const char *format, ...);
>  void pr_list_end(void);
>  void pr_sep(void);
>  void pr_struct_err(const char *format, ...);
> 
> 
> -- 
> Jean Delvare
> SUSE L3 Support

-- 

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Jerry Hoemann                  Software Engineer   Hewlett Packard Enterprise
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