From: Florian Weimer <fweimer@redhat.com>
To: Andreas Schwab <schwab@suse.de>
Cc: libc-alpha@sourceware.org
Subject: Re: [PATCH] wcsmbs: Fix data race in __wcsmbs_clone_conv [BZ #24584]
Date: Mon, 20 May 2019 19:18:14 +0200 [thread overview]
Message-ID: <875zq5hwo9.fsf@oldenburg2.str.redhat.com> (raw)
In-Reply-To: <mvmo93xjebq.fsf@suse.de> (Andreas Schwab's message of "Mon, 20 May 2019 18:11:37 +0200")
* Andreas Schwab:
> On Mai 20 2019, Florian Weimer <fweimer@redhat.com> wrote:
>
>> diff --git a/wcsmbs/wcsmbsload.c b/wcsmbs/wcsmbsload.c
>> index 5494d0a23e..e33a9c1312 100644
>> --- a/wcsmbs/wcsmbsload.c
>> +++ b/wcsmbs/wcsmbsload.c
>> @@ -20,6 +20,7 @@
>> #include <langinfo.h>
>> #include <limits.h>
>> #include <stdlib.h>
>> +#include <stdio.h>
>> #include <string.h>
>>
>> #include <locale/localeinfo.h>
>> @@ -223,12 +224,24 @@ __wcsmbs_clone_conv (struct gconv_fcts *copy)
>> /* Copy the data. */
>> *copy = *orig;
>>
>> - /* Now increment the usage counters.
>> - Note: This assumes copy->*_nsteps == 1. */
>> + /* Now increment the usage counters. Note: This assumes
>> + copy->*_nsteps == 1. The current locale holds a reference, so it
>> + is still there after acquiring the lock. */
>> +
>> + __libc_lock_lock (__gconv_lock);
>> +
>> + bool overflow = false;
>> if (copy->towc->__shlib_handle != NULL)
>> - ++copy->towc->__counter;
>> + overflow |= __builtin_add_overflow (copy->towc->__counter, 1,
>> + ©->towc->__counter);
>> if (copy->tomb->__shlib_handle != NULL)
>> - ++copy->tomb->__counter;
>> + overflow |= __builtin_add_overflow (copy->tomb->__counter, 1,
>> + ©->tomb->__counter);
>> + if (overflow)
>> + __libc_fatal ("\
>> +Fatal glibc error: gconv module reference counter overflow\n");
>> +
>> + __libc_lock_unlock (__gconv_lock);
>
> Should the lock be dropped before __libc_fatal?
I think this is purely a matter of style because __libc_fatal does not
return. Do you have a preference?
Thanks,
Florian
next prev parent reply other threads:[~2019-05-20 17:18 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-20 11:40 [PATCH] wcsmbs: Fix data race in __wcsmbs_clone_conv [BZ #24584] Florian Weimer
2019-05-20 12:26 ` Andreas Schwab
2019-05-20 13:28 ` Florian Weimer
2019-05-20 16:11 ` Andreas Schwab
2019-05-20 17:18 ` Florian Weimer [this message]
2019-05-21 7:15 ` Andreas Schwab
2019-05-21 8:38 ` Florian Weimer
2019-05-21 9:04 ` Andreas Schwab
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