Re: [PATCH v3 1/4] poll() exits too early with EFAULT if 1st arg is NULL
- From
Joachim Schmitz <jojo@schmitz-digital.de>
- Date
- Sep 13, 2012, 07:15 UTC
- Message-ID
- <k2s177$l37$1@ger.gmane.org>
- In-Reply-To
- <k2n79l$s9e$1@ger.gmane.org>
Joachim Schmitz wrote:
Show 30 quoted lines
> Joachim Schmitz wrote:
>> If poll() is used as a milli-second sleep, like in help.c, by passing
>> a NULL in the 1st and a 0 in the 2nd arg, it exits with EFAULT.
>>
>> As per Paolo Bonzini, the original author, this is a bug and to be
>> fixed like in this commit, which is not to exit if the 2nd arg is 0.
>>
>> Signed-off-by: Joachim Schmitz <jojo@schmitz-digital.de>
>> ---
>> compat/win32/poll.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/compat/win32/poll.c b/compat/win32/poll.c
>> index 403eaa7..9e7a25c 100644
>> --- a/compat/win32/poll.c
>> +++ b/compat/win32/poll.c
>> @@ -349,7 +349,7 @@ poll (struct pollfd *pfd, nfds_t nfd, int
>> timeout)
>>
>> /* EFAULT is not necessary to implement, but let's do it in the
>> simplest case. */
>> - if (!pfd)
>> + if (!pfd && nfd)
>> {
>> errno = EFAULT;
>> return -1;
>
> Actually this one is not needed for win32 (nor does win32 suffer from
> a similar bug), so should probably better get added after patch 2/2
> (or as part of it), the move to compat/poll/.It just got added that was to gnulib, with a commit message of:
don't exit early if NULL is the 1st arg to poll(), but nfd is 0. In that case poll should behave like select.
Bye, Jojo