search for: prepcore

The prescription for Boot Info Table says that checksumming begins at byte 64 of isolinux.bin. When prepcore writes isolinux.bin it begins copying bytes from the input file at the offset given by variable "start". But it begins checksumming at offset 64 of the input file. The problem exists since introduction of prepcore by release 4.00. ISO 9660 programs usually fix it when they write the Boot...

Hi, i think i found a suspect in lzo/prepcore.c and it would indeed be a wrong range of checksumming (speculative congratulations to Ady). Looking at http://repo.or.cz/syslinux.git/blob/0d82b71304d596d80f3c4520f9dcf90048ca50b7:/lzo/prepcore.c it seems that this change in line 374 could yield correct checksums: unsigned int ptr; -...

...r lacking > knowledge), do not patch the boot info table. I agree and still riddle about the reason. > So, my question is whether there is some intentional reason for these > changes in isolinux.bin. I assume that hpa intended to move the functionality of checksumiso.pl into the "prepcore" helper program which compresses all or parts of the ./core/*.bin files. > What I'd like to know is what > happened with the "default" checksum in isolinux.bin, To my theory it fell victim to a bug. > how is/are the checksum(s) calculated now? To my best knowledge b...

...> http://repo.or.cz/syslinux.git/blob/f1aa00224b23e2b4c71f204c1417c7b6e5ea8e51:/core/isolinux.asm#l213 > up to line 220. > > So i assume that checksumming still is applied somehow during building of > isolinux.bin. > > In the diff of core/Makefile i see a new program ../lzo/prepcore applied. > In its source, one can see the Boot Info Table checksum calculation: > http://repo.or.cz/syslinux.git/blob/0d82b71304d596d80f3c4520f9dcf90048ca50b7:/lzo/prepcore.c#l370 > It looks to me as if it computes the checksum of payload and block padding. > (This explains why the in...

Sorry Gene, I got the version of binutils is 2.17. I download the latest Binutils to make the *objdump* and *objcopy*. with both of these utilities to create new pxelinux.raw. then, the error message shows me that, objcopy -O binary pxelinux.elf pxelinux.raw ../lzo/prepcore pxelinux.raw pxelinux.bin ../lzo/prepcore: pxelinux.raw: output too big (30165, max 0) make[1]: *** [pxelinux.bin] Error 1 so, i thought maybe there is something wrong with the format of the pxelinux.raw. is that right? thanks aaron ----- Original Message ----- From: <syslinux-request at z...

...2.07. Because I'm looking for information about that gpxelinux->chain.c32 hd0 boot problem I added -DDEBUG=2 to com32/lib/Makefile I get: objdump -h pxelinux.elf > pxelinux.sec perl lstadjust.pl pxelinux.lsr pxelinux.sec pxelinux.lst objcopy -O binary pxelinux.elf pxelinux.raw ../lzo/prepcore pxelinux.raw pxelinux.bin ../lzo/prepcore: pxelinux.raw: output too big (29120, max 0) make[1]: *** [pxelinux.bin] Error 1 Would someone please enlight me how to fix this? Thanks Thomas

Hi, Is anyone compiled a new pxelinux.0 with syslinux code 4.03? right now, I got a error in compiling this version code, objdump -h pxelinux.elf > pxelinux.sec perl lstadjust.pl pxelinux.lsr pxelinux.sec pxelinux.lst objcopy -O binary pxelinux.elf pxelinux.raw ../lzo/prepcore pxelinux.raw pxelinux.bin ../lzo/prepcore: pxelinux.raw: output too big (30197, max 0) make[1]: *** [pxelinux.bin] Error 1 rm ldlinux.raw isolinux-debug.raw pxelinux.raw isolinux.raw ldlinux.o pxelinux.o isolinux.o isolinux-debug.o make[1]: Leaving directory `/root/syslinux-4.03/core' make: ***...

...48 bytes). ----------------------------------------------------------------------------- The "primary volume descriptor" of a first session on medium is always at Logical Block Address 16 = 0x10 0x00 0x00 0x00. "Boot file length" and "32-bit checksum" get filled in by prepcore and do not change by the -boot-info-table changes. Nevertheless the ISO producer programs set these values too. > G_ I have not tested isolinux-debug.bin nor any isohybrid features. I understand that the isohybrid MBR loads and runs the first 2048 bytes of isolinux.bin like BIOS would do with...

> Hi, > > i think i found a suspect in lzo/prepcore.c and it would indeed be a > wrong range of checksumming (speculative congratulations to Ady). Thank you Thomas for your replies and for looking into this issue. My part on the initial investigation that triggered this email thread is relatively small. Others deserve much more credit. I wa...

...ion of binutils is 2.17. > > I download the latest Binutils to make the *objdump* and *objcopy*. with > > both of these utilities to create new pxelinux.raw. > > then, the error message shows me that, > > > > objcopy -O binary pxelinux.elf pxelinux.raw > > ../lzo/prepcore pxelinux.raw pxelinux.bin > > ../lzo/prepcore: pxelinux.raw: output too big (30165, max 0) > > make[1]: *** [pxelinux.bin] Error 1 > > not simple to compile binutils properly > > so, i thought maybe there is something wrong with the format of the > > pxelinux.raw. &gt...

..... $ rpm --query --file /usr/bin/objcopy binutils-2.26-4.fc24.x86_64 $ cd syslinux-7cd1ed6/ $ make bios ... objcopy -O binary -S ldlinux.elf ldlinux.raw objcopy -O binary -S isolinux.elf isolinux.raw objcopy -O binary -S isolinux-debug.elf isolinux-debug.raw /tmp/syslinux-7cd1ed6/bios/core/../lzo/prepcore ldlinux.raw ldlinux.bin objdump -h pxelinux.elf > pxelinux.sec perl /tmp/syslinux-7cd1ed6/core/lstadjust.pl pxelinux.lsr pxelinux.sec pxelinux.lst objdump -h lpxelinux.elf > lpxelinux.sec perl /tmp/syslinux-7cd1ed6/core/lstadjust.pl lpxelinux.lsr lpxelinux.sec lpxelinux.lst /tmp/syslinux-7cd1...

I was thinking... Perhaps I should just change any "isolinux" term with some f*ing off-topic crap while maintaining the same proposed patch; then maybe we would get some relevant (re)action about this issue from The Syslinux Project? diff --git a/lzo/prepcore.c b/lzo/prepcore.c index 9147b2e4..b5ebe88b 100644 --- a/lzo/prepcore.c +++ b/lzo/prepcore.c @@ -331,7 +331,7 @@ int main(int argc, char *argv[]) unsigned int ptr; outfile_len = ((offset - start + out_len + 2047) & ~2047) - (offset - start); - for (ptr = 64; ptr < offset; ptr += 4)...

...--start-group libcore.a ../com32/lib/libcomcore.a /usr/lib/gcc/i386-redhat-linux/4.1.2/libgcc.a --end-group \ > isolinux.map objdump -h isolinux.elf > isolinux.sec perl lstadjust.pl isolinux.lsr isolinux.sec isolinux.lst objcopy -O binary isolinux.elf isolinux.raw ../lzo/prepcore isolinux.raw isolinux.bin nasm -f elf -Ox -g -F dwarf -DDATE_STR="'0x5110300a'" \ -DHEXDATE="0x5110300a" \ -l isolinux-debug.lsr -o isolinux-debug.o -MP -MD .isolinux-debug.o.d isolinux-debug.asm ld -m elf_i386 -T syslinux.ld -M -o isolin...

...ect repository [0]. Until a release come out that render them useless of course. Best Regards, Ben. [0] https://git.busybox.net/buildroot/tree/boot/syslinux Beno?t Allard (4): memdisk: Force ld output format to 32-bits utils: Use the host toolchain to build. lzo: Use the host toolchain for prepcore efi/wrapper: build it with the host toolchain. efi/Makefile | 2 +- lzo/Makefile | 7 +++++-- memdisk/Makefile | 2 +- utils/Makefile | 12 ++++++------ 4 files changed, 13 insertions(+), 10 deletions(-) -- 2.1.4

...ore the initial byte pattern before testing with offset 0 instead of 64. The observations match my theory about the missing addition of "start" when beginning the checksum loop, if "start" is 64. > Since I am not a developer, I cannot avoid wondering whether patching > prepcore.c would have additional consequences. The change should only influence the checksum, which can hardly get worse. It comes to me that a run of old checksumiso.pl should have the same effect as putting isolinux.bin into an ISO. I.e. test would be whether the four bytes at offset 20 of a freshly bui...

Until Syslinux 3.86, isolinux.bin contained a checksum that was calculated by 'core/checksumiso.pl'. The checksum is related to the patching of the boot info table. During May 2009, a commit by Peter deleted the checksumiso.pl file. The commit is: core: LZO compress the PM part of the core repo.or.cz/syslinux.git/commit/0d82b71304d596d80f3c4520f9dcf90048ca50b7 And so, since

On Thu, 2018-10-18 at 12:14 +0200, Didier Spaier via Syslinux wrote: > CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe. > > > On 10/17/18 8:54 PM, KARBOWSKI Piotr via Syslinux wrote: > > Is syslinux still under active development? I do not see any new commit in

...v = rv = vsnprintf(buffer, BUFFER_SIZE, format, ap); - + rv = vsnprintf(buffer, BUFFER_SIZE, format, ap); if (rv < 0) return; diff --git a/core/Makefile b/core/Makefile index 3147566..a01d83a 100644 --- a/core/Makefile +++ b/core/Makefile @@ -62,7 +62,7 @@ NASMOPT += $(NASMDEBUG) PREPCORE = ../lzo/prepcore -CFLAGS += -DDEBUG=1 -D__SYSLINUX_CORE__ +CFLAGS += -D__SYSLINUX_CORE__ # The DATE is set on the make command line when building binaries for # official release. Otherwise, substitute a hex string that is pretty much

...0xdeadbeef See the comments from http://repo.or.cz/syslinux.git/blob/f1aa00224b23e2b4c71f204c1417c7b6e5ea8e51:/core/isolinux.asm#l213 up to line 220. So i assume that checksumming still is applied somehow during building of isolinux.bin. In the diff of core/Makefile i see a new program ../lzo/prepcore applied. In its source, one can see the Boot Info Table checksum calculation: http://repo.or.cz/syslinux.git/blob/0d82b71304d596d80f3c4520f9dcf90048ca50b7:/lzo/prepcore.c#l370 It looks to me as if it computes the checksum of payload and block padding. (This explains why the installed isolinux.bin...

...es the board resets and than it starts without any problem. We have seen this with syslinux 4.00 and 4.02. Is this problem known? How can we investigate it further? So far we were not able to rebuild pxelinux.0 on a RedHat4 system to add debug info (additional printf), the file gets too large for prepcore. Is it possible to post the output of the original make process to check any differences ( I have gcc 4.2.3 and nasm 2.09) or at least the version of the tooling needed? (I am very interested in the thread How to compile syslinux 4.03) In the past, version 3.70 of syslinux, I was able to build pxel...