Syslinux - May 2014 - [PATCH] isohybrid: fix overflow on 32 bit system

On 2014?05?12? 22:38, H. Peter Anvin wrote:
> That is because it needs to use fseeko() and use off_t.
Do you mean it does need a patch for isohybrid.c. And the patch looks like:

#if _FILE_OFFSET_BITS == 64
     fseeko(...)
#else
    fseek(...)


Regards,
Kai
>
> On May 11, 2014 11:53:17 PM PDT, Kang Kai <Kai.Kang at windriver.com>
wrote:
>> On 2014?05?12? 10:49, H. Peter Anvin wrote:
>>> On 05/11/2014 06:56 PM, Kai Kang wrote:
>>>> When call isohybrid with option '-u', it overflows on a
32 bits
>> host. It
>>>> seeks to 512 bytes before the end of the image to install gpt
>> header. If
>>>> the size of image is larger than LONG_MAX, it overflows fseek()
and
>>>> cause error:
>>>>
>>>> isohybrid: wrlinux-image-x86-64-20140505110100.iso: seek error
- 8:
>> Invalid argument
>>>> Check the offset and call fseek() multi-times if offset is too
>> large.
>>>> Signed-off-by: Kai Kang <kai.kang at windriver.com>
>>> NAK.
>>>
>>> The right thing to do is compile it with #define _FILE_OFFSET_BITS
64
>>> and change fseek to fseeko with the appropriate type being off_t.
>>>
>>> 	-hpa
>> Hi hpa,
>>
>> Thanks for your reply.
>>
>> In utils/Makefile, -D_FILE_OFFSET_BITS=64 is added to CFLAGS. isohybrid
>>
>> is compiled with -D_FILE_OFFSET_BITS=64 but it still fails to handle
>> the
>> large offset.
>>
>> make[3]: Entering directory
>>
`/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/work/i686-linux/syslinux-native/6.01-r0/syslinux-6.01/bios/utils'
>> gcc
>>
-isystem/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/sysroots/i686-linux/usr/include
>>
>> -O2 -pipe -Wp,-MT,isohybrid.o,-MMD,./.isohybrid.o.d -W -Wall
>> -Wstrict-prototypes -Os -fomit-frame-pointer *-D_FILE_OFFSET_BITS=64*
>>
-I/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/work/i686-linux/syslinux-native/6.01-r0/syslinux-6.01/utils
>>
>> -c -o isohybrid.o
>>
/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/work/i686-linux/syslinux-native/6.01-r0/syslinux-6.01/utils/isohybrid.c
>>
>> I build it on RedHat Enterprise Linux 6.2 with glibc 2.12.
>>
>> Regards,
>> Kai
>>

-- 
Regards,
Neil | Kai Kang

No #if.

On May 12, 2014 6:26:18 PM PDT, Kang Kai <Kai.Kang at windriver.com>
wrote:
>On 2014?05?12? 22:38, H. Peter Anvin wrote:
>> That is because it needs to use fseeko() and use off_t.
>
>Do you mean it does need a patch for isohybrid.c. And the patch looks
>like:
>
>#if _FILE_OFFSET_BITS == 64
>     fseeko(...)
>#else
>    fseek(...)
>
>
>Regards,
>Kai
>
>>
>> On May 11, 2014 11:53:17 PM PDT, Kang Kai <Kai.Kang at
windriver.com>
>wrote:
>>> On 2014?05?12? 10:49, H. Peter Anvin wrote:
>>>> On 05/11/2014 06:56 PM, Kai Kang wrote:
>>>>> When call isohybrid with option '-u', it overflows
on a 32 bits
>>> host. It
>>>>> seeks to 512 bytes before the end of the image to install
gpt
>>> header. If
>>>>> the size of image is larger than LONG_MAX, it overflows
fseek()
>and
>>>>> cause error:
>>>>>
>>>>> isohybrid: wrlinux-image-x86-64-20140505110100.iso: seek
error -
>8:
>>> Invalid argument
>>>>> Check the offset and call fseek() multi-times if offset is
too
>>> large.
>>>>> Signed-off-by: Kai Kang <kai.kang at windriver.com>
>>>> NAK.
>>>>
>>>> The right thing to do is compile it with #define
_FILE_OFFSET_BITS
>64
>>>> and change fseek to fseeko with the appropriate type being
off_t.
>>>>
>>>> 	-hpa
>>> Hi hpa,
>>>
>>> Thanks for your reply.
>>>
>>> In utils/Makefile, -D_FILE_OFFSET_BITS=64 is added to CFLAGS.
>isohybrid
>>>
>>> is compiled with -D_FILE_OFFSET_BITS=64 but it still fails to
handle
>>> the
>>> large offset.
>>>
>>> make[3]: Entering directory
>>>
>`/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/work/i686-linux/syslinux-native/6.01-r0/syslinux-6.01/bios/utils'
>>> gcc
>>>
>-isystem/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/sysroots/i686-linux/usr/include
>>>
>>> -O2 -pipe -Wp,-MT,isohybrid.o,-MMD,./.isohybrid.o.d -W -Wall
>>> -Wstrict-prototypes -Os -fomit-frame-pointer
>*-D_FILE_OFFSET_BITS=64*
>>>
>-I/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/work/i686-linux/syslinux-native/6.01-r0/syslinux-6.01/utils
>>>
>>> -c -o isohybrid.o
>>>
>/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/work/i686-linux/syslinux-native/6.01-r0/syslinux-6.01/utils/isohybrid.c
>>>
>>> I build it on RedHat Enterprise Linux 6.2 with glibc 2.12.
>>>
>>> Regards,
>>> Kai
>>>
-- 
Sent from my mobile phone.  Please pardon brevity and lack of formatting.

On 2014?05?13? 09:29, H. Peter Anvin wrote:
> No #if.
OK. I'll send V2.

Thanks,
Kai
>
> On May 12, 2014 6:26:18 PM PDT, Kang Kai <Kai.Kang at windriver.com>
wrote:
>> On 2014?05?12? 22:38, H. Peter Anvin wrote:
>>> That is because it needs to use fseeko() and use off_t.
>> Do you mean it does need a patch for isohybrid.c. And the patch looks
>> like:
>>
>> #if _FILE_OFFSET_BITS == 64
>>      fseeko(...)
>> #else
>>     fseek(...)
>>
>>
>> Regards,
>> Kai
>>
>>> On May 11, 2014 11:53:17 PM PDT, Kang Kai <Kai.Kang at
windriver.com>
>> wrote:
>>>> On 2014?05?12? 10:49, H. Peter Anvin wrote:
>>>>> On 05/11/2014 06:56 PM, Kai Kang wrote:
>>>>>> When call isohybrid with option '-u', it
overflows on a 32 bits
>>>> host. It
>>>>>> seeks to 512 bytes before the end of the image to
install gpt
>>>> header. If
>>>>>> the size of image is larger than LONG_MAX, it overflows
fseek()
>> and
>>>>>> cause error:
>>>>>>
>>>>>> isohybrid: wrlinux-image-x86-64-20140505110100.iso:
seek error -
>> 8:
>>>> Invalid argument
>>>>>> Check the offset and call fseek() multi-times if offset
is too
>>>> large.
>>>>>> Signed-off-by: Kai Kang <kai.kang at
windriver.com>
>>>>> NAK.
>>>>>
>>>>> The right thing to do is compile it with #define
_FILE_OFFSET_BITS
>> 64
>>>>> and change fseek to fseeko with the appropriate type being
off_t.
>>>>>
>>>>> 	-hpa
>>>> Hi hpa,
>>>>
>>>> Thanks for your reply.
>>>>
>>>> In utils/Makefile, -D_FILE_OFFSET_BITS=64 is added to CFLAGS.
>> isohybrid
>>>> is compiled with -D_FILE_OFFSET_BITS=64 but it still fails to
handle
>>>> the
>>>> large offset.
>>>>
>>>> make[3]: Entering directory
>>>>
>>
`/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/work/i686-linux/syslinux-native/6.01-r0/syslinux-6.01/bios/utils'
>>>> gcc
>>>>
>>
-isystem/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/sysroots/i686-linux/usr/include
>>>> -O2 -pipe -Wp,-MT,isohybrid.o,-MMD,./.isohybrid.o.d -W -Wall
>>>> -Wstrict-prototypes -Os -fomit-frame-pointer
>> *-D_FILE_OFFSET_BITS=64*
>>
-I/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/work/i686-linux/syslinux-native/6.01-r0/syslinux-6.01/utils
>>>> -c -o isohybrid.o
>>>>
>>
/home/neil/wrlinux/builds/install-x86-64/bitbake_build/tmp/work/i686-linux/syslinux-native/6.01-r0/syslinux-6.01/utils/isohybrid.c
>>>> I build it on RedHat Enterprise Linux 6.2 with glibc 2.12.
>>>>
>>>> Regards,
>>>> Kai
>>>>

-- 
Regards,
Neil | Kai Kang