From d48016d748363ab34d91d06925bf8d2cfd1a6c72 Mon Sep 17 00:00:00 2001 From: Rik van Riel Date: Thu, 17 Aug 2023 13:57:59 -0400 Subject: [PATCH] mm,ima,kexec,of: use memblock_free_late from ima_free_kexec_buffer commit f0362a253606e2031f8d61c74195d4d6556e12a4 upstream. The code calling ima_free_kexec_buffer runs long after the memblock allocator has already been torn down, potentially resulting in a use after free in memblock_isolate_range. With KASAN or KFENCE, this use after free will result in a BUG from the idle task, and a subsequent kernel panic. Switch ima_free_kexec_buffer over to memblock_free_late to avoid that issue. Fixes: fee3ff99bc67 ("powerpc: Move arch independent ima kexec functions to drivers/of/kexec.c") Cc: stable@kernel.org Signed-off-by: Rik van Riel Suggested-by: Mike Rappoport Link: https://lore.kernel.org/r/20230817135759.0888e5ef@imladris.surriel.com Signed-off-by: Rob Herring Signed-off-by: Mike Rappoport (IBM) Signed-off-by: Greg Kroah-Hartman --- drivers/of/kexec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c index 52bb68fb2216..3a07cc58e7d7 100644 --- a/drivers/of/kexec.c +++ b/drivers/of/kexec.c @@ -187,8 +187,8 @@ int ima_free_kexec_buffer(void) if (ret) return ret; - return memblock_free(addr, size); - + memblock_free_late(addr, size); + return 0; } /**