path: root/lib/Kconfig.ubsan
diff options
authorArnd Bergmann <>2021-01-23 21:01:48 -0800
committerLinus Torvalds <>2021-01-24 10:34:52 -0800
commit251b5497c5c95e4548e3d33cbda3f638fea2c11e (patch)
tree80f486ad5848355d1f8dc9662e0814c734a8b3f2 /lib/Kconfig.ubsan
parentacb35b177c71d3d39b9a3b9ea213d926235066e3 (diff)
ubsan: disable unsigned-overflow check for i386
Building ubsan kernels even for compile-testing introduced these warnings in my randconfig environment: crypto/blake2b_generic.c:98:13: error: stack frame size of 9636 bytes in function 'blake2b_compress' [-Werror,-Wframe-larger-than=] static void blake2b_compress(struct blake2b_state *S, crypto/sha512_generic.c:151:13: error: stack frame size of 1292 bytes in function 'sha512_generic_block_fn' [-Werror,-Wframe-larger-than=] static void sha512_generic_block_fn(struct sha512_state *sst, u8 const *src, lib/crypto/curve25519-fiat32.c:312:22: error: stack frame size of 2180 bytes in function 'fe_mul_impl' [-Werror,-Wframe-larger-than=] static noinline void fe_mul_impl(u32 out[10], const u32 in1[10], const u32 in2[10]) lib/crypto/curve25519-fiat32.c:444:22: error: stack frame size of 1588 bytes in function 'fe_sqr_impl' [-Werror,-Wframe-larger-than=] static noinline void fe_sqr_impl(u32 out[10], const u32 in1[10]) Further testing showed that this is caused by -fsanitize=unsigned-integer-overflow, but is isolated to the 32-bit x86 architecture. The one in blake2b immediately overflows the 8KB stack area architectures, so better ensure this never happens by disabling the option for 32-bit x86. Link: Link: Fixes: d0a3ac549f38 ("ubsan: enable for all*config builds") Signed-off-by: Arnd Bergmann <> Acked-by: Kees Cook <> Reviewed-by: Nathan Chancellor <> Cc: Nick Desaulniers <> Cc: Stephen Rothwell <> Cc: Marco Elver <> Cc: George Popescu <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'lib/Kconfig.ubsan')
1 files changed, 1 insertions, 0 deletions
diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan
index 8b635fd75fe4..3a0b1c930733 100644
--- a/lib/Kconfig.ubsan
+++ b/lib/Kconfig.ubsan
@@ -123,6 +123,7 @@ config UBSAN_SIGNED_OVERFLOW
bool "Perform checking for unsigned arithmetic overflow"
depends on $(cc-option,-fsanitize=unsigned-integer-overflow)
+ depends on !X86_32 # avoid excessive stack usage on x86-32/clang
This option enables -fsanitize=unsigned-integer-overflow which checks
for overflow of any arithmetic operations with unsigned integers. This