The commit
cb51a371d0 ("EDAC/ghes: Setup DIMM label from DMI and use it in error reports")
enforced that both the bank and device strings passed to
dimm_setup_label() are not NULL.
However, there are BIOSes, for example on a
HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 03/15/2019
which don't populate both strings:
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
This results in a buffer overflow because ghes_edac_register() calls
strlen() on an uninitialized label, which had non-zero values left over
from krealloc_array():
detected buffer overflow in __fortify_strlen
------------[ cut here ]------------
kernel BUG at lib/string_helpers.c:983!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 1 Comm: swapper/0 Tainted: G I 5.18.6-200.fc36.x86_64 #1
Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 03/15/2019
RIP: 0010:fortify_panic
...
Call Trace:
<TASK>
ghes_edac_register.cold
ghes_probe
platform_probe
really_probe
__driver_probe_device
driver_probe_device
__driver_attach
? __device_attach_driver
bus_for_each_dev
bus_add_driver
driver_register
acpi_ghes_init
acpi_init
? acpi_sleep_proc_init
do_one_initcall
The label contains garbage because the commit in Fixes reallocs the
DIMMs array while scanning the system but doesn't clear the newly
allocated memory.
Change dimm_setup_label() to always initialize the label to fix the
issue. Set it to the empty string in case BIOS does not provide both
bank and device so that ghes_edac_register() can keep the default label
given by edac_mc_alloc_dimms().
[ bp: Rewrite commit message. ]
Fixes: b9cae27728 ("EDAC/ghes: Scan the system once on driver init")
Co-developed-by: Robert Richter <rric@kernel.org>
Signed-off-by: Robert Richter <rric@kernel.org>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Robert Elliott <elliott@hpe.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220719220124.760359-1-toshi.kani@hpe.com
5e2805d537