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-rw-r--r--arch/arm/include/asm/assembler.h4
-rw-r--r--arch/arm/include/asm/thread_info.h4
-rw-r--r--arch/arm/include/asm/uaccess.h26
-rw-r--r--arch/arm/kernel/entry-common.S4
-rw-r--r--arch/arm/kernel/head-nommu.S2
-rw-r--r--arch/arm/kernel/signal.c58
-rw-r--r--arch/arm/kernel/sys_oabi-compat.c8
-rw-r--r--arch/arm/lib/copy_from_user.S9
-rw-r--r--arch/arm/mm/init.c9
-rw-r--r--arch/arm/vfp/vfpmodule.c17
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;
}
/*