Merge branches 'fixes', 'misc' and 'spectre' into for-linus
authorRussell King <rmk+kernel@armlinux.org.uk>
Mon, 13 Aug 2018 15:28:50 +0000 (16:28 +0100)
committerRussell King <rmk+kernel@armlinux.org.uk>
Mon, 13 Aug 2018 15:28:50 +0000 (16:28 +0100)
Conflicts:
arch/arm/include/asm/uaccess.h

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
arch/arm/include/asm/assembler.h
arch/arm/include/asm/thread_info.h
arch/arm/include/asm/uaccess.h
arch/arm/kernel/entry-common.S
arch/arm/kernel/head-nommu.S
arch/arm/kernel/signal.c
arch/arm/kernel/sys_oabi-compat.c
arch/arm/lib/copy_from_user.S
arch/arm/mm/init.c
arch/arm/vfp/vfpmodule.c

index 0cd4dccbae788626ddd277376d1dc78c719a9ff2..b17ee03d280b6ff9ff706f04ab4d3be57f20bfe8 100644 (file)
@@ -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
 
index e71cc35de16335af87a878abaf5530166111a8fd..9b37b6ab27fe052eb8225c811688700c6ae99bb3 100644 (file)
@@ -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
 
 /*
index 3d614e90c19f307ac04b3e625c52b6bc80b66da7..5451e1f05a193c002f3b30af921975a28c232833 100644 (file)
@@ -84,6 +84,13 @@ static inline void set_fs(mm_segment_t fs)
                : "cc"); \
        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
@@ -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)                         \
index 106a1466518d0a24f29ee64ec364f8f1d1034d62..746565a876dcdd362522d1e546c8404faacfbfe2 100644 (file)
@@ -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)
index 724734039492c753f61cf9430065ae18fd5b2b18..ec29de2500764e11ad839bda165c135f12b6a6e5 100644 (file)
@@ -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]
index f09e9d66d605f4159990ad044cfd29486d621d20..5cc5a4259d03ca16079c4ff29463267b553c2c92 100644 (file)
@@ -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);
 
index 1df21a61e379e1a0fe66e784c7a1212814b100da..f0dd4b6ebb6330e5007e883d2ba2d099a4e1df94 100644 (file)
@@ -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) {
index 7a4b060490012dd29f8a6d9fb8e24dfa58896bd1..a826df3d3814bfef44d6e6f71b38c8131d9fe25b 100644 (file)
        .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"
 
index c186474422f3fb25cb809a6d0bff48f476ef8595..0cc8e04295a40dc1d16f308396afdfb7540aa48c 100644 (file)
@@ -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);
 }
index 35d0f823e8239f99f29596bc9805c9ab0bae467f..dc7e6b50ef674839a21480c69e12bec144d19194 100644 (file)
@@ -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;
 }
 
 /*