Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
On Fri, 2007-10-05 at 18:41 +0200, Carl-Daniel Hailfinger wrote: On 03.10.2007 01:48, Alex Beregszaszi wrote: On Sat, 2007-09-29 at 23:49 +0200, Carl-Daniel Hailfinger wrote: On 12.09.2007 21:37, Alex Beregszaszi wrote: Hi, On Fri, 2007-09-07 at 12:54 +0200, Alex Beregszaszi wrote: Hi, On Wed, 2007-09-05 at 04:29 +0200, Stefan Reinauer wrote: * Alex Beregszaszi [EMAIL PROTECTED] [070904 13:17]: Hi, the attached patch adds code to checksum the pci extension rom and stop if the stored and calculated checksum differ. Is this checksum reliably correct? I am hesitating to add new restrictions that might break otherwise working cards. You are right, attached is a correct method. There is no fixed checksum byte, instead the whole should sum to zero. Any comments on this? I like it. I'd give you an Ack, but I have no hardware to test with. Stefan? Ron? Worst case would be that buggy extension ROMs break with a really loud warning, so anybody with such ROMs will see it prominently in the logs. Alex: Is there an easy way to check extension ROMs in the current machine for correct signatures? Maybe standalone utility or such stuff. There is no utility for that, but you could copy out the memory between 0xc - 0xf0 from /dev/mem and search for extension headers in it (see the code in pci_rom.c). Can you commit with the following changelog? The attached patch adds code to checksum the pci extension rom and abort if the stored and calculated checksum differ. Worst case would be that buggy extension ROMs break with a really loud warning, so anybody with such ROMs will see it prominently in the logs. There is no easy way to check extension ROMs in the current machine for correct signatures, but you could copy out the memory between 0xc - 0xf0 from /dev/mem and search for extension headers in it (see the code in pci_rom.c). Acked-by: Carl-Daniel Hailfinger [EMAIL PROTECTED] Finally done. -- Alex -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
On Wed, Oct 17, 2007 at 11:30:30AM +0200, Stefan Reinauer wrote:
Is this checksum reliably correct? I am hesitating to add new
restrictions that might break otherwise working cards.
You are right, attached is a correct method. There is no fixed checksum
byte, instead the whole should sum to zero.
--
Alex
Signed-off-by: Alex Beregszaszi [EMAIL PROTECTED]
Acked-by: Stefan Reinauer [EMAIL PROTECTED]
Index: device/pci_rom.c
===
--- device/pci_rom.c(revision 494)
+++ device/pci_rom.c(working copy)
@@ -33,6 +33,8 @@
unsigned long rom_address;
struct rom_header *rom_header;
struct pci_data *rom_data;
+ unsigned int i;
+ unsigned char sum = 0, *rom_bytes;
if (dev-on_mainboard) {
/* In case some device PCI_ROM_ADDRESS can not be set
@@ -67,7 +69,17 @@
le32_to_cpu(rom_header-signature));
return NULL;
}
+
+ /* checksum */
+ rom_bytes = (unsigned char *)rom_address;
+ for (i = 0; i rom_header-size * 512; i++)
+ sum += *(rom_bytes + i);
+ if (sum != 0) {
+ printk(BIOS_ERR, Incorrent Expansion ROM checksum (%02x !=
0)\n, sum);
+ return NULL;
+ }
Doesn't this mean it'll abort upon incorrect checksum? If so, NACK.
This should be a warning only, and not abort execution.
If it's implemented as warning only (without aborting):
Acked-by: Uwe Hermann [EMAIL PROTECTED]
Uwe.
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Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
On Thu, Oct 25, 2007 at 02:08:21AM +0200, Peter Stuge wrote: On Thu, Oct 18, 2007 at 12:27:27AM -0700, ron minnich wrote: what logs? What if [..] there is no serial console (sun ultra40) Debug port? Yes, but not everybody has that. In the worst case, even if you _do_ have the hardware, the USB controller might not support the Debug Port functionality. I agree with Ron that this should be a warning only (without aborting upon incorrect checksum, just warning about it). Uwe. -- http://www.hermann-uwe.de | http://www.holsham-traders.de http://www.crazy-hacks.org | http://www.unmaintained-free-software.org signature.asc Description: Digital signature -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
On Thu, Oct 18, 2007 at 12:27:27AM -0700, ron minnich wrote: what logs? What if [..] there is no serial console (sun ultra40) Debug port? //Peter -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
On 9/12/07, Alex Beregszaszi [EMAIL PROTECTED] wrote: Any comments on this? It worries me, given the habit pc vendors have of shipping broken IRQ, ACPI, and other tables, to make us dependent on them actually getting the checksum correct. Unless and until we do some testing to verify that the checksums are correct on a lot of cards, I would rather make this a warning rather than an error. Look at it this way. What is a factory bios going to do with an expansion card with a bad checksum? My bet is they run it. ron -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
On 10/5/07, Carl-Daniel Hailfinger [EMAIL PROTECTED] wrote: Worst case would be that buggy extension ROMs break with a really loud warning, so anybody with such ROMs will see it prominently in the logs. what logs? What if it is the VGA BIOS and there is no serial console (sun ultra40) There is no easy way to check extension ROMs in the current machine for correct signatures, I am not sure I agree with this. There are ways to do this check. ron -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
* Alex Beregszaszi [EMAIL PROTECTED] [070907 12:54]:
Hi,
On Wed, 2007-09-05 at 04:29 +0200, Stefan Reinauer wrote:
* Alex Beregszaszi [EMAIL PROTECTED] [070904 13:17]:
Hi,
the attached patch adds code to checksum the pci extension rom and stop
if the stored and calculated checksum differ.
Is this checksum reliably correct? I am hesitating to add new
restrictions that might break otherwise working cards.
You are right, attached is a correct method. There is no fixed checksum
byte, instead the whole should sum to zero.
--
Alex
Signed-off-by: Alex Beregszaszi [EMAIL PROTECTED]
Acked-by: Stefan Reinauer [EMAIL PROTECTED]
Index: device/pci_rom.c
===
--- device/pci_rom.c (revision 494)
+++ device/pci_rom.c (working copy)
@@ -33,6 +33,8 @@
unsigned long rom_address;
struct rom_header *rom_header;
struct pci_data *rom_data;
+ unsigned int i;
+ unsigned char sum = 0, *rom_bytes;
if (dev-on_mainboard) {
/* In case some device PCI_ROM_ADDRESS can not be set
@@ -67,7 +69,17 @@
le32_to_cpu(rom_header-signature));
return NULL;
}
+
+ /* checksum */
+ rom_bytes = (unsigned char *)rom_address;
+ for (i = 0; i rom_header-size * 512; i++)
+ sum += *(rom_bytes + i);
+ if (sum != 0) {
+ printk(BIOS_ERR, Incorrent Expansion ROM checksum (%02x !=
0)\n, sum);
+ return NULL;
+ }
+
rom_data = (struct pci_data *)((unsigned char *)rom_header +
le32_to_cpu(rom_header-data));
--
coresystems GmbH • Brahmsstr. 16 • D-79104 Freiburg i. Br.
Tel.: +49 761 7668825 • Fax: +49 761 7664613
Email: [EMAIL PROTECTED] • http://www.coresystems.de/
Registergericht: Amtsgericht Freiburg • HRB 7656
Geschäftsführer: Stefan Reinauer • Ust-IdNr.: DE245674866
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Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
On 03.10.2007 01:48, Alex Beregszaszi wrote: On Sat, 2007-09-29 at 23:49 +0200, Carl-Daniel Hailfinger wrote: On 12.09.2007 21:37, Alex Beregszaszi wrote: Hi, On Fri, 2007-09-07 at 12:54 +0200, Alex Beregszaszi wrote: Hi, On Wed, 2007-09-05 at 04:29 +0200, Stefan Reinauer wrote: * Alex Beregszaszi [EMAIL PROTECTED] [070904 13:17]: Hi, the attached patch adds code to checksum the pci extension rom and stop if the stored and calculated checksum differ. Is this checksum reliably correct? I am hesitating to add new restrictions that might break otherwise working cards. You are right, attached is a correct method. There is no fixed checksum byte, instead the whole should sum to zero. Any comments on this? I like it. I'd give you an Ack, but I have no hardware to test with. Stefan? Ron? Worst case would be that buggy extension ROMs break with a really loud warning, so anybody with such ROMs will see it prominently in the logs. Alex: Is there an easy way to check extension ROMs in the current machine for correct signatures? Maybe standalone utility or such stuff. There is no utility for that, but you could copy out the memory between 0xc - 0xf0 from /dev/mem and search for extension headers in it (see the code in pci_rom.c). Can you commit with the following changelog? The attached patch adds code to checksum the pci extension rom and abort if the stored and calculated checksum differ. Worst case would be that buggy extension ROMs break with a really loud warning, so anybody with such ROMs will see it prominently in the logs. There is no easy way to check extension ROMs in the current machine for correct signatures, but you could copy out the memory between 0xc - 0xf0 from /dev/mem and search for extension headers in it (see the code in pci_rom.c). Acked-by: Carl-Daniel Hailfinger [EMAIL PROTECTED] Regards, Carl-Daniel -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
On Sat, 2007-09-29 at 23:49 +0200, Carl-Daniel Hailfinger wrote: On 12.09.2007 21:37, Alex Beregszaszi wrote: Hi, On Fri, 2007-09-07 at 12:54 +0200, Alex Beregszaszi wrote: Hi, On Wed, 2007-09-05 at 04:29 +0200, Stefan Reinauer wrote: * Alex Beregszaszi [EMAIL PROTECTED] [070904 13:17]: Hi, the attached patch adds code to checksum the pci extension rom and stop if the stored and calculated checksum differ. Is this checksum reliably correct? I am hesitating to add new restrictions that might break otherwise working cards. You are right, attached is a correct method. There is no fixed checksum byte, instead the whole should sum to zero. Any comments on this? I like it. I'd give you an Ack, but I have no hardware to test with. Stefan? Ron? Worst case would be that buggy extension ROMs break with a really loud warning, so anybody with such ROMs will see it prominently in the logs. Alex: Is there an easy way to check extension ROMs in the current machine for correct signatures? Maybe standalone utility or such stuff. There is no utility for that, but you could copy out the memory between 0xc - 0xf0 from /dev/mem and search for extension headers in it (see the code in pci_rom.c). -- Alex -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
On 12.09.2007 21:37, Alex Beregszaszi wrote: Hi, On Fri, 2007-09-07 at 12:54 +0200, Alex Beregszaszi wrote: Hi, On Wed, 2007-09-05 at 04:29 +0200, Stefan Reinauer wrote: * Alex Beregszaszi [EMAIL PROTECTED] [070904 13:17]: Hi, the attached patch adds code to checksum the pci extension rom and stop if the stored and calculated checksum differ. Is this checksum reliably correct? I am hesitating to add new restrictions that might break otherwise working cards. You are right, attached is a correct method. There is no fixed checksum byte, instead the whole should sum to zero. Any comments on this? I like it. I'd give you an Ack, but I have no hardware to test with. Stefan? Ron? Worst case would be that buggy extension ROMs break with a really loud warning, so anybody with such ROMs will see it prominently in the logs. Alex: Is there an easy way to check extension ROMs in the current machine for correct signatures? Maybe standalone utility or such stuff. Carl-Daniel -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
Hi, On Fri, 2007-09-07 at 12:54 +0200, Alex Beregszaszi wrote: Hi, On Wed, 2007-09-05 at 04:29 +0200, Stefan Reinauer wrote: * Alex Beregszaszi [EMAIL PROTECTED] [070904 13:17]: Hi, the attached patch adds code to checksum the pci extension rom and stop if the stored and calculated checksum differ. Is this checksum reliably correct? I am hesitating to add new restrictions that might break otherwise working cards. You are right, attached is a correct method. There is no fixed checksum byte, instead the whole should sum to zero. Any comments on this? -- Alex -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
Hi,
On Wed, 2007-09-05 at 04:29 +0200, Stefan Reinauer wrote:
* Alex Beregszaszi [EMAIL PROTECTED] [070904 13:17]:
Hi,
the attached patch adds code to checksum the pci extension rom and stop
if the stored and calculated checksum differ.
Is this checksum reliably correct? I am hesitating to add new
restrictions that might break otherwise working cards.
You are right, attached is a correct method. There is no fixed checksum
byte, instead the whole should sum to zero.
--
Alex
Signed-off-by: Alex Beregszaszi [EMAIL PROTECTED]
Index: device/pci_rom.c
===
--- device/pci_rom.c (revision 494)
+++ device/pci_rom.c (working copy)
@@ -33,6 +33,8 @@
unsigned long rom_address;
struct rom_header *rom_header;
struct pci_data *rom_data;
+ unsigned int i;
+ unsigned char sum = 0, *rom_bytes;
if (dev-on_mainboard) {
/* In case some device PCI_ROM_ADDRESS can not be set
@@ -67,7 +69,17 @@
le32_to_cpu(rom_header-signature));
return NULL;
}
+
+ /* checksum */
+ rom_bytes = (unsigned char *)rom_address;
+ for (i = 0; i rom_header-size * 512; i++)
+ sum += *(rom_bytes + i);
+ if (sum != 0) {
+ printk(BIOS_ERR, Incorrent Expansion ROM checksum (%02x != 0)\n, sum);
+ return NULL;
+ }
+
rom_data = (struct pci_data *)((unsigned char *)rom_header +
le32_to_cpu(rom_header-data));
--
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Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
Hi, On Wed, 2007-09-05 at 04:29 +0200, Stefan Reinauer wrote: * Alex Beregszaszi [EMAIL PROTECTED] [070904 13:17]: Hi, the attached patch adds code to checksum the pci extension rom and stop if the stored and calculated checksum differ. Is this checksum reliably correct? I am hesitating to add new restrictions that might break otherwise working cards. This algorithm is used in vgabios to set the checksum, and bochsbios to check the option roms. If you think this makes too much restrictions, you might make this only a warning and not a fail condition. Or defined under a PARANOID_SECURITY option :) -- Alex Beregszaszi -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
[LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
Hi,
the attached patch adds code to checksum the pci extension rom and stop
if the stored and calculated checksum differ.
--
Alex
Index: device/pci_rom.c
===
--- device/pci_rom.c (revision 486)
+++ device/pci_rom.c (working copy)
@@ -33,6 +33,8 @@
unsigned long rom_address;
struct rom_header *rom_header;
struct pci_data *rom_data;
+ unsigned int i;
+ unsigned char sum = 0, *rom_bytes;
if (dev-on_mainboard) {
/* In case some device PCI_ROM_ADDRESS can not be set
@@ -67,7 +69,19 @@
le32_to_cpu(rom_header-signature));
return NULL;
}
+
+ /* checksum */
+ rom_bytes = (unsigned char *)rom_address;
+ for (i = 0; i rom_header-size * 512 - 1; i++)
+ sum += *(rom_bytes + i);
+ sum = -sum;
+ if (sum != *(rom_bytes + rom_header-size * 512 - 1)) {
+ printk(BIOS_ERR, Incorrent Expansion ROM checksum (%02x != %02x)\n,
+ *(rom_bytes + rom_header-size * 512 - 1), sum);
+ return NULL;
+ }
+
rom_data = (struct pci_data *)((unsigned char *)rom_header +
le32_to_cpu(rom_header-data));
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Re: [LinuxBIOS] [PATCH] pci_rom.c checksum extension rom
* Alex Beregszaszi [EMAIL PROTECTED] [070904 13:17]: Hi, the attached patch adds code to checksum the pci extension rom and stop if the stored and calculated checksum differ. Is this checksum reliably correct? I am hesitating to add new restrictions that might break otherwise working cards. -- coresystems GmbH • Brahmsstr. 16 • D-79104 Freiburg i. Br. Tel.: +49 761 7668825 • Fax: +49 761 7664613 Email: [EMAIL PROTECTED] • http://www.coresystems.de/ -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
