v5: drop redundant checks (gustavo) v4: https://lore.kernel.org/linux-hardening/20240206102354.make.081-k...@kernel.org/ v3: https://lore.kernel.org/all/20240205090854.make.507-k...@kernel.org/ v2: https://lore.kernel.org/all/20240130220218.it.154-k...@kernel.org/ v1: https://lore.kernel.org/lkml/20240129182845.work.694-k...@kernel.org/
Hi, In preparation for gaining instrumentation for signed[1], unsigned[2], and pointer[3] wrap-around, expand the overflow header to include wrap-around helpers that can be used to annotate arithmetic where wrapped calculations are expected (e.g. atomics). After spending time getting the unsigned integer wrap-around sanitizer running warning-free on a basic x86_64 boot[4], I think the add/sub/mul helpers first argument being the output type makes the most sense (as suggested by Rasmus). -Kees Kees Cook (3): overflow: Adjust check_*_overflow() kern-doc to reflect results overflow: Introduce wrapping_add(), wrapping_sub(), and wrapping_mul() overflow: Introduce wrapping_inc() and wrapping_dec() include/linux/overflow.h | 98 +++++++++++++++++++++++++++++++++++----- lib/overflow_kunit.c | 67 +++++++++++++++++++++++++-- 2 files changed, 149 insertions(+), 16 deletions(-) -- 2.34.1
