Commit Message
Greg KH
Oct. 19, 2022, 8:25 a.m. UTC
From: Jason A. Donenfeld <Jason@zx2c4.com> [ Upstream commit 7c236d93c6764dcaca7ab66d76768a044647876d ] The RNG seed boot record is memzeroed after processing, in order to preserve forward secrecy. By saving the bootinfo for procfs prior to that, forward secrecy is violated, since it becomes possible to recover past states. So, save the bootinfo block only after first processing them. Fixes: a1ee38ab1a75 ("m68k: virt: Use RNG seed from bootinfo block") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Link: https://lore.kernel.org/r/20220927130835.1629806-1-Jason@zx2c4.com Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- arch/m68k/kernel/setup_mm.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/m68k/kernel/setup_mm.c b/arch/m68k/kernel/setup_mm.c index e62fa8f2149b..7e7ef67cff8b 100644 --- a/arch/m68k/kernel/setup_mm.c +++ b/arch/m68k/kernel/setup_mm.c @@ -109,10 +109,9 @@ extern void paging_init(void); static void __init m68k_parse_bootinfo(const struct bi_record *record) { + const struct bi_record *first_record = record; uint16_t tag; - save_bootinfo(record); - while ((tag = be16_to_cpu(record->tag)) != BI_LAST) { int unknown = 0; const void *data = record->data; @@ -182,6 +181,8 @@ static void __init m68k_parse_bootinfo(const struct bi_record *record) record = (struct bi_record *)((unsigned long)record + size); } + save_bootinfo(first_record); + m68k_realnum_memory = m68k_num_memory; #ifdef CONFIG_SINGLE_MEMORY_CHUNK if (m68k_num_memory > 1) {