RE: [PATCH] EDAC/ghes: Fix buffer overflow in ghes_edac_register()

Kani, Toshi
2022-07-20T15:41:44Z

Borislav Petkov wrote:
> On Tue, Jul 19, 2022 at 04:01:24PM -0600, Toshi Kani wrote:
> > The following buffer overflow BUG was observed on an HPE system.
> > ghes_edac_register() called strlen() on an uninitialized label, which
> > had non-zero values from krealloc_array().
> > Change dimm_setup_label() to always initialize the label.
>
> Do we also know why dmi_memdev_name() doesn't give bank and/or device?

Yes.

> SMBIOS handle wrong?

SMBIOS handle is correct.

In dimm_setup_label(), *device is set but *bank is null (dmi_empty_string).
*bank is set from SMBIOS type 17 Bank Locator, offset 11h. This value is
set to 0x0 (null string) on this system, as shown below.

Handle 0x0020, DMI type 17, 84 bytes
Memory Device
Array Handle: 0x0013
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 32 GB
Form Factor: DIMM
Set: None
Locator: PROC 1 DIMM 1 <===== device
Bank Locator: Not Specified <===== bank
....

Handle 0x0020, DMI type 17, 84 bytes
Header and Data:
11 54 20 00 13 00 FE FF 48 00 40 00 FF 7F 09 00
01 00 1A 80 20 75 0B 02 00 00 03 02 00 80 00 00
^^
75 0B B0 04 B0 04 B0 04 03 08 00 00 89 83 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
08 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00
Strings:
50 52 4F 43 20 31 20 44 49 4D 4D 20 31 00
PROC 1 DIMM 1
55 4E 4B 4E 4F 57 4E 00
UNKNOWN
4E 4F 54 20 41 56 41 49 4C 41 42 4C 45 00
NOT AVAILABLE

Thanks,
Toshi