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Re: [PATCH] locale: don't crash if locale-archive is an empty file
- From: "Carlos O'Donell" <carlos at redhat dot com>
- To: Aurelien Jarno <aurelien at aurel32 dot net>
- Cc: libc-alpha at sourceware dot org
- Date: Fri, 29 Nov 2013 14:35:28 -0500
- Subject: Re: [PATCH] locale: don't crash if locale-archive is an empty file
- Authentication-results: sourceware.org; auth=none
- References: <1385739561-27038-1-git-send-email-aurelien at aurel32 dot net> <5298C293 dot 4030503 at redhat dot com> <20131129165804 dot GB4601 at hall dot aurel32 dot net>
On 11/29/2013 11:58 AM, Aurelien Jarno wrote:
> On Fri, Nov 29, 2013 at 11:36:35AM -0500, Carlos O'Donell wrote:
>> On 11/29/2013 10:39 AM, Aurelien Jarno wrote:
>>> In case of power failure followed by filesystem issues locale-archive
>>> can end-up containing all zeros. In that case all calls to setlocale()
>>> generate a SIGFPE. This renders a system with a default non-C locale
>>> Avoid this by ignoring the locale instead of generating a SIGFPE.
>>> locale/loadarchive.c | 4 ++++
>>> 1 file changed, 4 insertions(+)
>>> 2013-11-29 Aurelien Jarno <email@example.com>
>>> * locale/loadarchive.c (_nl_load_locale_from_archive): Avoid
>>> division by 0.
>>> diff --git a/locale/loadarchive.c b/locale/loadarchive.c
>>> index 70136dc..7cfc498 100644
>>> --- a/locale/loadarchive.c
>>> +++ b/locale/loadarchive.c
>>> @@ -274,6 +274,10 @@ _nl_load_locale_from_archive (int category, const char **namep)
>>> namehashtab = (struct namehashent *) ((char *) head
>>> + head->namehash_offset);
>>> + /* Avoid division by 0 if the file is corrupted. */
>>> + if (__builtin_expect (head->namehash_size == 0, 0))
>>> + goto close_and_out;
>>> idx = hval % head->namehash_size;
>>> incr = 1 + hval % (head->namehash_size - 2);
>> How did you test this?
> I fetched a broken locale-archive from  and set the environment
> variables LANG="en_IN" and LANGUAGE="en_IN:en" (though I have been able
> to reproduce with my default locales setting). Then all coreutils
> commands started to SIGFPE (ls, mount, su, grep, etc.).
> In installed the fixed version of the libc, and all commands started
> to work again.
That's a pretty big test with a lot of variables.
Could you please test this with a small program that calls setlocale
for both a non-builtin and builtin locale?
OK to checkin given testing with a smaller more concise test that
proves there aren't any other factors involved here.