Joe reports that using a statically allocated buffer for converting CPER error records into human readable text is probably a bad idea. Even though we are not aware of any actual issues, a stack buffer is clearly a better choice here anyway, so let's move the buffer into the stack frames of the two functions that refer to it.

Cc: stable@vger.kernel.org Reported-by: Joe Perches joe@perches.com Signed-off-by: Ard Biesheuvel ardb@kernel.org --- drivers/firmware/efi/cper.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/cper.c b/drivers/firmware/efi/cper.c index 73bdbd207e7a..6ec8edec6329 100644 --- a/drivers/firmware/efi/cper.c +++ b/drivers/firmware/efi/cper.c @@ -25,8 +25,6 @@ #include <acpi/ghes.h> #include <ras/ras_event.h>

-static char rcd_decode_str[CPER_REC_LEN]; - /* * CPER record ID need to be unique even after reboot, because record * ID is used as index for ERST storage, while CPER records from @@ -312,6 +310,7 @@ const char *cper_mem_err_unpack(struct trace_seq *p, struct cper_mem_err_compact *cmem) { const char *ret = trace_seq_buffer_ptr(p); + char rcd_decode_str[CPER_REC_LEN];

if (cper_mem_err_location(cmem, rcd_decode_str)) trace_seq_printf(p, "%s", rcd_decode_str); @@ -326,6 +325,7 @@ static void cper_print_mem(const char *pfx, const struct cper_sec_mem_err *mem, int len) { struct cper_mem_err_compact cmem; + char rcd_decode_str[CPER_REC_LEN];

/* Don't trust UEFI 2.1/2.2 structure with bad validation bits */ if (len == sizeof(struct cper_sec_mem_err_old) &&