diff options
-rw-r--r-- | arch/arm/include/asm/assembler.h | 4 | ||||
-rw-r--r-- | arch/arm/include/asm/thread_info.h | 4 | ||||
-rw-r--r-- | arch/arm/include/asm/uaccess.h | 26 | ||||
-rw-r--r-- | arch/arm/kernel/entry-common.S | 4 | ||||
-rw-r--r-- | arch/arm/kernel/head-nommu.S | 2 | ||||
-rw-r--r-- | arch/arm/kernel/signal.c | 58 | ||||
-rw-r--r-- | arch/arm/kernel/sys_oabi-compat.c | 8 | ||||
-rw-r--r-- | arch/arm/lib/copy_from_user.S | 9 | ||||
-rw-r--r-- | arch/arm/mm/init.c | 9 | ||||
-rw-r--r-- | arch/arm/vfp/vfpmodule.c | 17 |
10 files changed, 88 insertions, 53 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index 0cd4dccbae78..b17ee03d280b 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -460,6 +460,10 @@ THUMB( orr \reg , \reg , #PSR_T_BIT ) adds \tmp, \addr, #\size - 1 sbcccs \tmp, \tmp, \limit bcs \bad +#ifdef CONFIG_CPU_SPECTRE + movcs \addr, #0 + csdb +#endif #endif .endm diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index e71cc35de163..9b37b6ab27fe 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -123,8 +123,8 @@ struct user_vfp_exc; extern int vfp_preserve_user_clear_hwstate(struct user_vfp __user *, struct user_vfp_exc __user *); -extern int vfp_restore_user_hwstate(struct user_vfp __user *, - struct user_vfp_exc __user *); +extern int vfp_restore_user_hwstate(struct user_vfp *, + struct user_vfp_exc *); #endif /* diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index 3d614e90c19f..5451e1f05a19 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -85,6 +85,13 @@ static inline void set_fs(mm_segment_t fs) flag; }) /* + * This is a type: either unsigned long, if the argument fits into + * that type, or otherwise unsigned long long. + */ +#define __inttype(x) \ + __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) + +/* * Single-value transfer routines. They automatically use the right * size if we just have the right pointer type. Note that the functions * which read from user space (*get_*) need to take care not to leak @@ -153,7 +160,7 @@ extern int __get_user_64t_4(void *); ({ \ unsigned long __limit = current_thread_info()->addr_limit - 1; \ register typeof(*(p)) __user *__p asm("r0") = (p); \ - register typeof(x) __r2 asm("r2"); \ + register __inttype(x) __r2 asm("r2"); \ register unsigned long __l asm("r1") = __limit; \ register int __e asm("r0"); \ unsigned int __ua_flags = uaccess_save_and_enable(); \ @@ -243,6 +250,16 @@ static inline void set_fs(mm_segment_t fs) #define user_addr_max() \ (uaccess_kernel() ? ~0UL : get_fs()) +#ifdef CONFIG_CPU_SPECTRE +/* + * When mitigating Spectre variant 1, it is not worth fixing the non- + * verifying accessors, because we need to add verification of the + * address space there. Force these to use the standard get_user() + * version instead. + */ +#define __get_user(x, ptr) get_user(x, ptr) +#else + /* * The "__xxx" versions of the user access functions do not verify the * address space - it must have been done previously with a separate @@ -259,12 +276,6 @@ static inline void set_fs(mm_segment_t fs) __gu_err; \ }) -#define __get_user_error(x, ptr, err) \ -({ \ - __get_user_err((x), (ptr), err); \ - (void) 0; \ -}) - #define __get_user_err(x, ptr, err) \ do { \ unsigned long __gu_addr = (unsigned long)(ptr); \ @@ -324,6 +335,7 @@ do { \ #define __get_user_asm_word(x, addr, err) \ __get_user_asm(x, addr, err, ldr) +#endif #define __put_user_switch(x, ptr, __err, __fn) \ diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 106a1466518d..746565a876dc 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -48,6 +48,7 @@ saved_pc .req lr * from those features make this path too inefficient. */ ret_fast_syscall: +__ret_fast_syscall: UNWIND(.fnstart ) UNWIND(.cantunwind ) disable_irq_notrace @ disable interrupts @@ -78,6 +79,7 @@ fast_work_pending: * call. */ ret_fast_syscall: +__ret_fast_syscall: UNWIND(.fnstart ) UNWIND(.cantunwind ) str r0, [sp, #S_R0 + S_OFF]! @ save returned r0 @@ -255,7 +257,7 @@ local_restart: tst r10, #_TIF_SYSCALL_WORK @ are we tracing syscalls? bne __sys_trace - invoke_syscall tbl, scno, r10, ret_fast_syscall + invoke_syscall tbl, scno, r10, __ret_fast_syscall add r1, sp, #S_OFF 2: cmp scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE) diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index 724734039492..ec29de250076 100644 --- a/arch/arm/kernel/head-nommu.S +++ b/arch/arm/kernel/head-nommu.S @@ -185,7 +185,7 @@ M_CLASS(streq r3, [r12, #PMSAv8_MAIR1]) bic r0, r0, #CR_I #endif mcr p15, 0, r0, c1, c0, 0 @ write control reg - isb + instr_sync #elif defined (CONFIG_CPU_V7M) #ifdef CONFIG_ARM_MPU ldreq r3, [r12, MPU_CTRL] diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index f09e9d66d605..5cc5a4259d03 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -150,22 +150,18 @@ static int preserve_vfp_context(struct vfp_sigframe __user *frame) static int restore_vfp_context(char __user **auxp) { - struct vfp_sigframe __user *frame = - (struct vfp_sigframe __user *)*auxp; - unsigned long magic; - unsigned long size; - int err = 0; - - __get_user_error(magic, &frame->magic, err); - __get_user_error(size, &frame->size, err); + struct vfp_sigframe frame; + int err; + err = __copy_from_user(&frame, *auxp, sizeof(frame)); if (err) - return -EFAULT; - if (magic != VFP_MAGIC || size != VFP_STORAGE_SIZE) + return err; + + if (frame.magic != VFP_MAGIC || frame.size != VFP_STORAGE_SIZE) return -EINVAL; - *auxp += size; - return vfp_restore_user_hwstate(&frame->ufp, &frame->ufp_exc); + *auxp += sizeof(frame); + return vfp_restore_user_hwstate(&frame.ufp, &frame.ufp_exc); } #endif @@ -176,6 +172,7 @@ static int restore_vfp_context(char __user **auxp) static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf) { + struct sigcontext context; char __user *aux; sigset_t set; int err; @@ -184,23 +181,26 @@ static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf) if (err == 0) set_current_blocked(&set); - __get_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); - __get_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); - __get_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); - __get_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); - __get_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); - __get_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); - __get_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); - __get_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); - __get_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); - __get_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); - __get_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); - __get_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); - __get_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); - __get_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); - __get_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); - __get_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); - __get_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); + err |= __copy_from_user(&context, &sf->uc.uc_mcontext, sizeof(context)); + if (err == 0) { + regs->ARM_r0 = context.arm_r0; + regs->ARM_r1 = context.arm_r1; + regs->ARM_r2 = context.arm_r2; + regs->ARM_r3 = context.arm_r3; + regs->ARM_r4 = context.arm_r4; + regs->ARM_r5 = context.arm_r5; + regs->ARM_r6 = context.arm_r6; + regs->ARM_r7 = context.arm_r7; + regs->ARM_r8 = context.arm_r8; + regs->ARM_r9 = context.arm_r9; + regs->ARM_r10 = context.arm_r10; + regs->ARM_fp = context.arm_fp; + regs->ARM_ip = context.arm_ip; + regs->ARM_sp = context.arm_sp; + regs->ARM_lr = context.arm_lr; + regs->ARM_pc = context.arm_pc; + regs->ARM_cpsr = context.arm_cpsr; + } err |= !valid_user_regs(regs); diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c index 1df21a61e379..f0dd4b6ebb63 100644 --- a/arch/arm/kernel/sys_oabi-compat.c +++ b/arch/arm/kernel/sys_oabi-compat.c @@ -329,9 +329,11 @@ asmlinkage long sys_oabi_semtimedop(int semid, return -ENOMEM; err = 0; for (i = 0; i < nsops; i++) { - __get_user_error(sops[i].sem_num, &tsops->sem_num, err); - __get_user_error(sops[i].sem_op, &tsops->sem_op, err); - __get_user_error(sops[i].sem_flg, &tsops->sem_flg, err); + struct oabi_sembuf osb; + err |= __copy_from_user(&osb, tsops, sizeof(osb)); + sops[i].sem_num = osb.sem_num; + sops[i].sem_op = osb.sem_op; + sops[i].sem_flg = osb.sem_flg; tsops++; } if (timeout) { diff --git a/arch/arm/lib/copy_from_user.S b/arch/arm/lib/copy_from_user.S index 7a4b06049001..a826df3d3814 100644 --- a/arch/arm/lib/copy_from_user.S +++ b/arch/arm/lib/copy_from_user.S @@ -90,6 +90,15 @@ .text ENTRY(arm_copy_from_user) +#ifdef CONFIG_CPU_SPECTRE + get_thread_info r3 + ldr r3, [r3, #TI_ADDR_LIMIT] + adds ip, r1, r2 @ ip=addr+size + sub r3, r3, #1 @ addr_limit - 1 + cmpcc ip, r3 @ if (addr+size > addr_limit - 1) + movcs r1, #0 @ addr = NULL + csdb +#endif #include "copy_template.S" diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index c186474422f3..0cc8e04295a4 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -736,20 +736,29 @@ static int __mark_rodata_ro(void *unused) return 0; } +static int kernel_set_to_readonly __read_mostly; + void mark_rodata_ro(void) { + kernel_set_to_readonly = 1; stop_machine(__mark_rodata_ro, NULL, NULL); debug_checkwx(); } void set_kernel_text_rw(void) { + if (!kernel_set_to_readonly) + return; + set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), false, current->active_mm); } void set_kernel_text_ro(void) { + if (!kernel_set_to_readonly) + return; + set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), true, current->active_mm); } diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 35d0f823e823..dc7e6b50ef67 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -596,13 +596,11 @@ int vfp_preserve_user_clear_hwstate(struct user_vfp __user *ufp, } /* Sanitise and restore the current VFP state from the provided structures. */ -int vfp_restore_user_hwstate(struct user_vfp __user *ufp, - struct user_vfp_exc __user *ufp_exc) +int vfp_restore_user_hwstate(struct user_vfp *ufp, struct user_vfp_exc *ufp_exc) { struct thread_info *thread = current_thread_info(); struct vfp_hard_struct *hwstate = &thread->vfpstate.hard; unsigned long fpexc; - int err = 0; /* Disable VFP to avoid corrupting the new thread state. */ vfp_flush_hwstate(thread); @@ -611,17 +609,16 @@ int vfp_restore_user_hwstate(struct user_vfp __user *ufp, * Copy the floating point registers. There can be unused * registers see asm/hwcap.h for details. */ - err |= __copy_from_user(&hwstate->fpregs, &ufp->fpregs, - sizeof(hwstate->fpregs)); + memcpy(&hwstate->fpregs, &ufp->fpregs, sizeof(hwstate->fpregs)); /* * Copy the status and control register. */ - __get_user_error(hwstate->fpscr, &ufp->fpscr, err); + hwstate->fpscr = ufp->fpscr; /* * Sanitise and restore the exception registers. */ - __get_user_error(fpexc, &ufp_exc->fpexc, err); + fpexc = ufp_exc->fpexc; /* Ensure the VFP is enabled. */ fpexc |= FPEXC_EN; @@ -630,10 +627,10 @@ int vfp_restore_user_hwstate(struct user_vfp __user *ufp, fpexc &= ~(FPEXC_EX | FPEXC_FP2V); hwstate->fpexc = fpexc; - __get_user_error(hwstate->fpinst, &ufp_exc->fpinst, err); - __get_user_error(hwstate->fpinst2, &ufp_exc->fpinst2, err); + hwstate->fpinst = ufp_exc->fpinst; + hwstate->fpinst2 = ufp_exc->fpinst2; - return err ? -EFAULT : 0; + return 0; } /* |