diff options
| author | Rik van Riel <riel@surriel.com> | 2023-08-17 13:55:58 -0400 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2023-09-18 09:24:15 +0200 |
| commit | 34cf99c250d5cd2530b93a57b0de31d3aaf8685b (patch) | |
| tree | 8708949831d43d7469ed8d74e2fe5f74a20aa503 /arch | |
| parent | ce9ecca0238b140b88f43859b211c9fdfd8e5b70 (diff) | |
x86/mm, kexec, ima: Use memblock_free_late() from ima_free_kexec_buffer()
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 bug.
Fixes: fee3ff99bc67 ("powerpc: Move arch independent ima kexec functions to drivers/of/kexec.c")
Suggested-by: Mike Rappoport <rppt@kernel.org>
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230817135558.67274c83@imladris.surriel.com
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/setup.c | 8 |
1 files changed, 2 insertions, 6 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index b9145a63da77..b098b1fa2470 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -358,15 +358,11 @@ static void __init add_early_ima_buffer(u64 phys_addr) #if defined(CONFIG_HAVE_IMA_KEXEC) && !defined(CONFIG_OF_FLATTREE) int __init ima_free_kexec_buffer(void) { - int rc; - if (!ima_kexec_buffer_size) return -ENOENT; - rc = memblock_phys_free(ima_kexec_buffer_phys, - ima_kexec_buffer_size); - if (rc) - return rc; + memblock_free_late(ima_kexec_buffer_phys, + ima_kexec_buffer_size); ima_kexec_buffer_phys = 0; ima_kexec_buffer_size = 0; |