EDAC/ghes: Set the DIMM label unconditionally
The commit cb51a371 ("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: b9cae277 ("EDAC/ghes: Scan the system once on driver init") Co-developed-by:Robert Richter <rric@kernel.org> Signed-off-by: