From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f74.google.com (mail-ej1-f74.google.com [209.85.218.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0B9E465A for ; Fri, 9 Sep 2022 07:38:55 +0000 (UTC) Received: by mail-ej1-f74.google.com with SMTP id oz30-20020a1709077d9e00b0077239b6a915so581855ejc.11 for ; Fri, 09 Sep 2022 00:38:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date; bh=CwJgI/zqEG/WNCJEuUp+CMHdoz4DAXmnbuoZdi14Bqk=; b=nx4UO6FGWdB0vzP8FiBCRGi6jWAecwwGmolsdjQeS05N/w/aqKfjKcXAYVgegeQje0 bqB/2LoH0zy2VvDaVaMjkhOmK7jEHBFQ0bxK8+tFG309lQiFZBL9hQqHXBqa2uHZ+ISO vSS9lWhdz4gtoi0yFjfirj42Ywv5YL08vEHsKsmwS2258lt8g8bziZI3VT42AtyowGTo tyUkMkyFR4ifx0HtUF53XLpG5aW87CT5KGtWoB0X2/5QUn+I+rUr79GU9LDlTZzsgUA+ MZRGI7gznSV5BWKds3sFjufh/v40H+2KpNALNG9bdu2PV75mdnduygY/DEZ1vQTGj20n JjAA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date; bh=CwJgI/zqEG/WNCJEuUp+CMHdoz4DAXmnbuoZdi14Bqk=; b=ECNL5hj5FyDfurcw5KJKPEOqCrPuf78WvACjErVROJVOuGEXeWrNGZB4rFciJlzmnu szDwNv4FAXK1X2awvOVmwIMdSV1LCmc3KJvT1C18SBhDyQDMeq1PgC8Bjj1bkRNf74UY pgV8TOz67KXd8xCO0VGNXAFQF2tL9ta2qF/a6bbnYRVesE+67YzQI73fid+tvp5YJS06 1RtVd7Oc2q+hCz5HdOamwkmQC2xtaI0kM3GEY7AHdhOnSUpmnrcNT58YGWwnx4PlIKEd jpmEcMeXwoLRit5EBbVoBD1o2g5i1erAH/uG/RkpOKdFY3bDvm/jXG7K/K4xCiW93LMQ 0LIA== X-Gm-Message-State: ACgBeo0k+7xQHSxfqy4Bq2+Kl0gzlClW/bsKRPBQihxcD/o2j0CmppsL y+HwLsGsCzQd0m6xguElh23HNt+gpw== X-Google-Smtp-Source: AA6agR55zHiBLxwKUigYV5E03IlRE8G/bXLTNM2ZQLcfJB47hg02LfbZ5lxPABjqhEP6sHcAmk436ldycg== X-Received: from elver.muc.corp.google.com ([2a00:79e0:9c:201:1d1e:ddcd:2020:36c2]) (user=elver job=sendgmr) by 2002:a17:907:3f26:b0:770:8852:9bed with SMTP id hq38-20020a1709073f2600b0077088529bedmr7603132ejc.658.1662709134191; Fri, 09 Sep 2022 00:38:54 -0700 (PDT) Date: Fri, 9 Sep 2022 09:38:39 +0200 In-Reply-To: <20220909073840.45349-1-elver@google.com> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20220909073840.45349-1-elver@google.com> X-Mailer: git-send-email 2.37.2.789.g6183377224-goog Message-ID: <20220909073840.45349-2-elver@google.com> Subject: [PATCH v2 2/3] kcsan: Instrument memcpy/memset/memmove with newer Clang From: Marco Elver To: elver@google.com, "Paul E. McKenney" Cc: Mark Rutland , Dmitry Vyukov , Alexander Potapenko , Boqun Feng , kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , llvm@lists.linux.dev, Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Peter Zijlstra , linux-s390@vger.kernel.org, stable@vger.kernel.org Content-Type: text/plain; charset="UTF-8" With Clang version 16+, -fsanitize=thread will turn memcpy/memset/memmove calls in instrumented functions into __tsan_memcpy/__tsan_memset/__tsan_memmove calls respectively. Add these functions to the core KCSAN runtime, so that we (a) catch data races with mem* functions, and (b) won't run into linker errors with such newer compilers. Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Marco Elver --- v2: * Fix for architectures which do not provide their own memcpy/memset/memmove and instead use the generic versions in lib/string. In this case we'll just alias the __tsan_ variants. --- kernel/kcsan/core.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c index fe12dfe254ec..4015f2a3e7f6 100644 --- a/kernel/kcsan/core.c +++ b/kernel/kcsan/core.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include "encoding.h" @@ -1308,3 +1309,41 @@ noinline void __tsan_atomic_signal_fence(int memorder) } } EXPORT_SYMBOL(__tsan_atomic_signal_fence); + +#ifdef __HAVE_ARCH_MEMSET +void *__tsan_memset(void *s, int c, size_t count); +noinline void *__tsan_memset(void *s, int c, size_t count) +{ + check_access(s, count, KCSAN_ACCESS_WRITE, _RET_IP_); + return __memset(s, c, count); +} +#else +void *__tsan_memset(void *s, int c, size_t count) __alias(memset); +#endif +EXPORT_SYMBOL(__tsan_memset); + +#ifdef __HAVE_ARCH_MEMMOVE +void *__tsan_memmove(void *dst, const void *src, size_t len); +noinline void *__tsan_memmove(void *dst, const void *src, size_t len) +{ + check_access(dst, len, KCSAN_ACCESS_WRITE, _RET_IP_); + check_access(src, len, 0, _RET_IP_); + return __memmove(dst, src, len); +} +#else +void *__tsan_memmove(void *dst, const void *src, size_t len) __alias(memmove); +#endif +EXPORT_SYMBOL(__tsan_memmove); + +#ifdef __HAVE_ARCH_MEMCPY +void *__tsan_memcpy(void *dst, const void *src, size_t len); +noinline void *__tsan_memcpy(void *dst, const void *src, size_t len) +{ + check_access(dst, len, KCSAN_ACCESS_WRITE, _RET_IP_); + check_access(src, len, 0, _RET_IP_); + return __memcpy(dst, src, len); +} +#else +void *__tsan_memcpy(void *dst, const void *src, size_t len) __alias(memcpy); +#endif +EXPORT_SYMBOL(__tsan_memcpy); -- 2.37.2.789.g6183377224-goog