[PATCH] fixup! setenv: align with POSIX in handling of setenv(var, "")

[Ahmad Fatoum]

Hello,

On 16.11.20 09:21, Sascha Hauer wrote:
> On Fri, Nov 13, 2020 at 09:26:00AM +0100, Ahmad Fatoum wrote:
>> Previously setenv xxx= deleted x like xxx= does. With xxx= now instead
>> assigning the empty string, setenv xxx= should too.
>>
>> Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
>>
>> ---
>>  commands/setenv.c | 3 +--
>>  1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/commands/setenv.c b/commands/setenv.c
>> index 6992f604f513..9aeb8f010bc5 100644
>> --- a/commands/setenv.c
>> +++ b/commands/setenv.c
>> @@ -18,8 +18,7 @@ static int do_setenv(int argc, char *argv[])
>>  	equal = strrchr(argv[1], '=');
>>  	if (equal) {
>>  		equal[0] = '\0';
>> -		if (equal[1])
>> -			argv[2] = &equal[1];
>> +		argv[2] = &equal[1];
>>  	}
> 
> Fine with me, but I just had a second look at fbf145dc86 ("commands: setenv:
> support setenv dev.var=VAL syntax"). This patch introduced using argv[2]
> when argc was only to, thus only argv[0] and argv[1] are valid. I wonder
> if this is allowed. KAsan doesn't complain, but still I think this
> should be changed. Could you do this before further modifying this?

barebox always has argv[argc] = NULL, so just like standard C, accessing
argv[2] here is fine.

See
  common/parser.c:29: argv[nargs] = NULL;
  common/hush.c:698:  pglob->gl_pathv[pathc] = NULL;
  lib/glob.c:398:     pglob->gl_pathv[pglob->gl_pathc] = NULL;
  lib/glob.c:232:     pglob->gl_pathv[pglob->gl_pathc] = NULL;

Cheers,
Ahmad
  


> 
> Sascha
> 

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