From 9562f3dc6f502d78fd5c8c56f5826e93b781bd46 Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Thu, 8 Apr 2021 11:28:40 -0700 Subject: [PATCH] arm64: add __nocfi to __apply_alternatives __apply_alternatives makes indirect calls to functions whose address is taken in assembly code using the alternative_cb macro. With non-canonical CFI, the compiler won't replace these function references with the jump table addresses, which trips CFI. Disable CFI checking in the function to work around the issue. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20210408182843.1754385-16-samitolvanen@google.com --- arch/arm64/kernel/alternative.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c index 1184c44ea2c7..abc84636af07 100644 --- a/arch/arm64/kernel/alternative.c +++ b/arch/arm64/kernel/alternative.c @@ -133,8 +133,8 @@ static void clean_dcache_range_nopatch(u64 start, u64 end) } while (cur += d_size, cur < end); } -static void __apply_alternatives(void *alt_region, bool is_module, - unsigned long *feature_mask) +static void __nocfi __apply_alternatives(void *alt_region, bool is_module, + unsigned long *feature_mask) { struct alt_instr *alt; struct alt_region *region = alt_region;