From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx49OcFBl5xE1JETdEZXFJnK5jV1naOAElutBLz38oU5ewmn3kaM8X77OUY64Ya2jWBohDYWm ARC-Seal: i=1; a=rsa-sha256; t=1522671905; cv=none; d=google.com; s=arc-20160816; b=rGNCkaLxVqUjNM9mepFMCnAPDiXwtyONP4dQRigvkkOApEnwHTts3CQLHb7rckyMnn zLW7D0QruSehGxKSoUSZ0IgZ7mAG1iMQvbjS5plpPKVyeffzJSvuOTmLLABCllzOvsCq FnnkRljFYzhW1VTjsdKtwp1IIrVQIzUlABDjJnxUl2eRBJ5aLUw/ViokumJgUnqp2WuH Do89HxuJ5ZTlqG0tjBLvkVtChOUObvx9cKokuNzNhTI74TWbloSEU8zXpW4J7Q7VOy95 grCUDpEaXQiMMXB6c1QzBTdStoOcYu8XdhsDFKWEJzqc9ACmg7stJh71y5V10GNQU6EY xIjw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:references:in-reply-to:message-id:date:subject:to:from :arc-authentication-results; bh=Gpb+7F6xZlAlrjXr4acQmvpbV+LDUn3PAW9kWPRDQ7Q=; b=K9JvpYST/7otlin9pb09aa375bBqT5dXu6/M17MHmvYjlggjUQzvVWVHF2E68OSF4b cph45l8mEWhqmzILKPWl+QtuMcBcta303/Ms8zgklvM7Ur48TgujY0W4R2V2wzvraGqM NRJ0ZqWwybRWCOE8bBdiTJGYhDzcEa9ROYR/PczeqlFRNfd92sY+ZXJ8OypgTQQBBMac 8Pgv6kTbITB9pcPVsdzX9cs9V1BDjZYTP/tcwEX6QG1yddEgSLIxVOVkUDrz0ASQVjj+ MTYZX8qKViFaRpBEyqHwERs0cLERrXF7lA5/+zwoHr8e9aMM9IouEr+xW8YFJ0cHfBLt FiWA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of liuwenliang@huawei.com designates 45.249.212.35 as permitted sender) smtp.mailfrom=liuwenliang@huawei.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of liuwenliang@huawei.com designates 45.249.212.35 as permitted sender) smtp.mailfrom=liuwenliang@huawei.com From: Abbott Liu To: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH v3 3/6] Replace memory function for kasan Date: Mon, 2 Apr 2018 20:04:37 +0800 Message-ID: <20180402120440.31900-4-liuwenliang@huawei.com> X-Mailer: git-send-email 2.9.0 In-Reply-To: <20180402120440.31900-1-liuwenliang@huawei.com> References: <20180402120440.31900-1-liuwenliang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.187.223] X-CFilter-Loop: Reflected X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1596637215476051533?= X-GMAIL-MSGID: =?utf-8?q?1596637215476051533?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: From: Andrey Ryabinin Functions like memset/memmove/memcpy do a lot of memory accesses. If bad pointer passed to one of these function it is important to catch this. Compiler's instrumentation cannot do this since these functions are written in assembly. KASan replaces memory functions with manually instrumented variants. Original functions declared as weak symbols so strong definitions in mm/kasan/kasan.c could replace them. Original functions have aliases with '__' prefix in name, so we could call non-instrumented variant if needed. We must use __memcpy/__memset to replace memcpy/memset when we copy .data to RAM and when we clear .bss, because kasan_early_init can't be called before the initialization of .data and .bss. Reviewed-by: Russell King - ARM Linux Acked-by: Florian Fainelli Tested-by: Florian Fainelli Tested-by: Joel Stanley Tested-by: Abbott Liu Signed-off-by: Abbott Liu --- arch/arm/boot/compressed/decompress.c | 2 ++ arch/arm/boot/compressed/libfdt_env.h | 2 ++ arch/arm/include/asm/string.h | 17 +++++++++++++++++ arch/arm/kernel/head-common.S | 4 ++-- arch/arm/lib/memcpy.S | 3 +++ arch/arm/lib/memmove.S | 5 ++++- arch/arm/lib/memset.S | 3 +++ 7 files changed, 33 insertions(+), 3 deletions(-) diff --git a/arch/arm/boot/compressed/decompress.c b/arch/arm/boot/compressed/decompress.c index a2ac3fe..0596077 100644 --- a/arch/arm/boot/compressed/decompress.c +++ b/arch/arm/boot/compressed/decompress.c @@ -49,8 +49,10 @@ extern int memcmp(const void *cs, const void *ct, size_t count); #endif #ifdef CONFIG_KERNEL_XZ +#ifndef CONFIG_KASAN #define memmove memmove #define memcpy memcpy +#endif #include "../../../../lib/decompress_unxz.c" #endif diff --git a/arch/arm/boot/compressed/libfdt_env.h b/arch/arm/boot/compressed/libfdt_env.h index 0743781..736ed36 100644 --- a/arch/arm/boot/compressed/libfdt_env.h +++ b/arch/arm/boot/compressed/libfdt_env.h @@ -17,4 +17,6 @@ typedef __be64 fdt64_t; #define fdt64_to_cpu(x) be64_to_cpu(x) #define cpu_to_fdt64(x) cpu_to_be64(x) +#undef memset + #endif diff --git a/arch/arm/include/asm/string.h b/arch/arm/include/asm/string.h index 111a1d8..1f9016b 100644 --- a/arch/arm/include/asm/string.h +++ b/arch/arm/include/asm/string.h @@ -15,15 +15,18 @@ extern char * strchr(const char * s, int c); #define __HAVE_ARCH_MEMCPY extern void * memcpy(void *, const void *, __kernel_size_t); +extern void *__memcpy(void *dest, const void *src, __kernel_size_t n); #define __HAVE_ARCH_MEMMOVE extern void * memmove(void *, const void *, __kernel_size_t); +extern void *__memmove(void *dest, const void *src, __kernel_size_t n); #define __HAVE_ARCH_MEMCHR extern void * memchr(const void *, int, __kernel_size_t); #define __HAVE_ARCH_MEMSET extern void * memset(void *, int, __kernel_size_t); +extern void *__memset(void *s, int c, __kernel_size_t n); #define __HAVE_ARCH_MEMSET32 extern void *__memset32(uint32_t *, uint32_t v, __kernel_size_t); @@ -39,4 +42,18 @@ static inline void *memset64(uint64_t *p, uint64_t v, __kernel_size_t n) return __memset64(p, v, n * 8, v >> 32); } + + +#if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__) + +/* + * For files that not instrumented (e.g. mm/slub.c) we + * should use not instrumented version of mem* functions. + */ + +#define memcpy(dst, src, len) __memcpy(dst, src, len) +#define memmove(dst, src, len) __memmove(dst, src, len) +#define memset(s, c, n) __memset(s, c, n) +#endif + #endif diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 6e0375e..c79b829 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -99,7 +99,7 @@ __mmap_switched: THUMB( ldmia r4!, {r0, r1, r2, r3} ) THUMB( mov sp, r3 ) sub r2, r2, r1 - bl memcpy @ copy .data to RAM + bl __memcpy @ copy .data to RAM #endif ARM( ldmia r4!, {r0, r1, sp} ) @@ -107,7 +107,7 @@ __mmap_switched: THUMB( mov sp, r3 ) sub r2, r1, r0 mov r1, #0 - bl memset @ clear .bss + bl __memset @ clear .bss ldmia r4, {r0, r1, r2, r3} str r9, [r0] @ Save processor ID diff --git a/arch/arm/lib/memcpy.S b/arch/arm/lib/memcpy.S index 64111bd..79a83f8 100644 --- a/arch/arm/lib/memcpy.S +++ b/arch/arm/lib/memcpy.S @@ -61,6 +61,8 @@ /* Prototype: void *memcpy(void *dest, const void *src, size_t n); */ +.weak memcpy +ENTRY(__memcpy) ENTRY(mmiocpy) ENTRY(memcpy) @@ -68,3 +70,4 @@ ENTRY(memcpy) ENDPROC(memcpy) ENDPROC(mmiocpy) +ENDPROC(__memcpy) diff --git a/arch/arm/lib/memmove.S b/arch/arm/lib/memmove.S index 69a9d47..313db6c 100644 --- a/arch/arm/lib/memmove.S +++ b/arch/arm/lib/memmove.S @@ -27,12 +27,14 @@ * occurring in the opposite direction. */ +.weak memmove +ENTRY(__memmove) ENTRY(memmove) UNWIND( .fnstart ) subs ip, r0, r1 cmphi r2, ip - bls memcpy + bls __memcpy stmfd sp!, {r0, r4, lr} UNWIND( .fnend ) @@ -225,3 +227,4 @@ ENTRY(memmove) 18: backward_copy_shift push=24 pull=8 ENDPROC(memmove) +ENDPROC(__memmove) diff --git a/arch/arm/lib/memset.S b/arch/arm/lib/memset.S index ed6d35d..64aa06a 100644 --- a/arch/arm/lib/memset.S +++ b/arch/arm/lib/memset.S @@ -16,6 +16,8 @@ .text .align 5 +.weak memset +ENTRY(__memset) ENTRY(mmioset) ENTRY(memset) UNWIND( .fnstart ) @@ -135,6 +137,7 @@ UNWIND( .fnstart ) UNWIND( .fnend ) ENDPROC(memset) ENDPROC(mmioset) +ENDPROC(__memset) ENTRY(__memset32) UNWIND( .fnstart ) -- 2.9.0