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Signed-off-by: Alexey Dobriyan --- lib/kstrtox.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/lib/kstrtox.c b/lib/kstrtox.c index 97be2a39f537..efd55db0533a 100644 --- a/lib/kstrtox.c +++ b/lib/kstrtox.c @@ -71,15 +71,11 @@ unsigned int _parse_integer_limit(const char *s, unsigned int base, unsigned lon if (val >= base) break; - /* - * Check for overflow only if we are within range of - * it in the max base we support (16) - */ - if (unlikely(res & (~0ull << 60))) { - if (res > div_u64(ULLONG_MAX - val, base)) - rv |= KSTRTOX_OVERFLOW; - } - res = res * base + val; + + if (check_mul_overflow(res, base, &res)) + rv |= KSTRTOX_OVERFLOW; + if (check_add_overflow(res, val, &res)) + rv |= KSTRTOX_OVERFLOW; rv++; s++; } -- 2.54.0