From: Paul Burton Date: Tue, 12 Dec 2017 09:57:47 +0000 (+0000) Subject: MIPS: VDSO: Prevent use of smp_processor_id() X-Git-Tag: v4.19-rc1~42^2~31 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=351fdddd366245c0fb4636f32edfb4198c8d6b8c;p=uclinux-h8%2Flinux.git MIPS: VDSO: Prevent use of smp_processor_id() VDSO code should not be using smp_processor_id(), since it is executed in user mode. Introduce a VDSO-specific path which will cause a compile-time or link-time error (depending upon support for __compiletime_error) if the VDSO ever incorrectly attempts to use smp_processor_id(). [Matt Redfearn : Move before change to smp_processor_id in series] Signed-off-by: Paul Burton Signed-off-by: Matt Redfearn Patchwork: https://patchwork.linux-mips.org/patch/17932/ Cc: Ralf Baechle Cc: James Hogan Cc: linux-mips@linux-mips.org --- diff --git a/arch/mips/include/asm/smp.h b/arch/mips/include/asm/smp.h index 88ebd83b3bf9..056a6bf13491 100644 --- a/arch/mips/include/asm/smp.h +++ b/arch/mips/include/asm/smp.h @@ -25,7 +25,17 @@ extern cpumask_t cpu_sibling_map[]; extern cpumask_t cpu_core_map[]; extern cpumask_t cpu_foreign_map[]; -#define raw_smp_processor_id() (current_thread_info()->cpu) +static inline int raw_smp_processor_id(void) +{ +#if defined(__VDSO__) + extern int vdso_smp_processor_id(void) + __compiletime_error("VDSO should not call smp_processor_id()"); + return vdso_smp_processor_id(); +#else + return current_thread_info()->cpu; +#endif +} +#define raw_smp_processor_id raw_smp_processor_id /* Map from cpu id to sequential logical cpu number. This will only not be idempotent when cpus failed to come on-line. */ diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile index ce196046ac3e..477c463c89ec 100644 --- a/arch/mips/vdso/Makefile +++ b/arch/mips/vdso/Makefile @@ -7,7 +7,8 @@ ccflags-vdso := \ $(filter -I%,$(KBUILD_CFLAGS)) \ $(filter -E%,$(KBUILD_CFLAGS)) \ $(filter -mmicromips,$(KBUILD_CFLAGS)) \ - $(filter -march=%,$(KBUILD_CFLAGS)) + $(filter -march=%,$(KBUILD_CFLAGS)) \ + -D__VDSO__ cflags-vdso := $(ccflags-vdso) \ $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \ -O2 -g -fPIC -fno-strict-aliasing -fno-common -fno-builtin -G 0 \