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(With the additional effect of turning UBSAN warnings into crashes, which may or may not be desired.) Signed-off-by: Jann Horn --- lib/Kconfig.ubsan | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan index efae7e011956..e4f19ba9a029 100644 --- a/lib/Kconfig.ubsan +++ b/lib/Kconfig.ubsan @@ -13,7 +13,7 @@ menuconfig UBSAN if UBSAN config UBSAN_TRAP - bool "On Sanitizer warnings, abort the running kernel code" + bool "Abort on Sanitizer warnings (smaller kernel but less verbose)" depends on !COMPILE_TEST help Building kernels with Sanitizer features enabled tends to grow @@ -26,6 +26,14 @@ config UBSAN_TRAP the system. For some system builders this is an acceptable trade-off. + CAUTION: Selecting Y will (depending on architecture) cause your + kernel to oops with an undefined instruction error with no further + details when a UBSAN violation occurs. + (arm64 can show some basic information.) + This may make it hard to determine whether an oops was caused by + UBSAN or to figure out the details of a UBSAN violation. + It makes the kernel log output less useful for bug reports. + config CC_HAS_UBSAN_BOUNDS_STRICT def_bool $(cc-option,-fsanitize=bounds-strict) help base-commit: d528014517f2b0531862c02865b9d4c908019dc4 -- 2.41.0.255.g8b1d071c50-goog