Merge tag 'arm64-stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas...

Pull arm64 fixes from Catalin Marinas:
 - Module compilation issues (symbol not exported).
 - Plug a hole where user space can bring the kernel down.

* tag 'arm64-stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: don't kill the kernel on a bad esr from el0
  arm64: treat unhandled compat el0 traps as undef
  arm64: Do not report user faults for handled signals
  arm64: kernel: compiling issue, need 'EXPORT_SYMBOL(clear_page)'

diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c
index 7df1aad29b676d38f085d9ca8be52a2d0c960431..41b4f626d5548c10985313839892de44ad81e1ec 100644 (file)
--- a/arch/arm64/kernel/arm64ksyms.c
+++ b/arch/arm64/kernel/arm64ksyms.c
@@ -34,6 +34,7 @@ EXPORT_SYMBOL(__strnlen_user);
 EXPORT_SYMBOL(__strncpy_from_user);
 
 EXPORT_SYMBOL(copy_page);
+EXPORT_SYMBOL(clear_page);
 
 EXPORT_SYMBOL(__copy_from_user);
 EXPORT_SYMBOL(__copy_to_user);

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index c7e047049f2c1e26db2534478b07db95ec29ede7..1d1314280a03a678c4ef63092712d49079386cdd 100644 (file)
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -390,6 +390,16 @@ el0_sync_compat:
        b.eq    el0_fpsimd_exc
        cmp     x24, #ESR_EL1_EC_UNKNOWN        // unknown exception in EL0
        b.eq    el0_undef
+       cmp     x24, #ESR_EL1_EC_CP15_32        // CP15 MRC/MCR trap
+       b.eq    el0_undef
+       cmp     x24, #ESR_EL1_EC_CP15_64        // CP15 MRRC/MCRR trap
+       b.eq    el0_undef
+       cmp     x24, #ESR_EL1_EC_CP14_MR        // CP14 MRC/MCR trap
+       b.eq    el0_undef
+       cmp     x24, #ESR_EL1_EC_CP14_LS        // CP14 LDC/STC trap
+       b.eq    el0_undef
+       cmp     x24, #ESR_EL1_EC_CP14_64        // CP14 MRRC/MCRR trap
+       b.eq    el0_undef
        cmp     x24, #ESR_EL1_EC_BREAKPT_EL0    // debug exception in EL0
        b.ge    el0_dbg
        b       el0_inv

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 61d7dd29f756c300926410cef60ab523a5a7a7b1..f30852d28590358c6780a22c14049f92a124bdb8 100644 (file)
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -267,7 +267,8 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
                return;
 #endif
 
-       if (show_unhandled_signals) {
+       if (show_unhandled_signals && unhandled_signal(current, SIGILL) &&
+           printk_ratelimit()) {
                pr_info("%s[%d]: undefined instruction: pc=%p\n",
                        current->comm, task_pid_nr(current), pc);
                dump_instr(KERN_INFO, regs);
@@ -294,7 +295,7 @@ asmlinkage long do_ni_syscall(struct pt_regs *regs)
        }
 #endif
 
-       if (show_unhandled_signals) {
+       if (show_unhandled_signals && printk_ratelimit()) {
                pr_info("%s[%d]: syscall %d\n", current->comm,
                        task_pid_nr(current), (int)regs->syscallno);
                dump_instr("", regs);
@@ -310,14 +311,20 @@ asmlinkage long do_ni_syscall(struct pt_regs *regs)
  */
 asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr)
 {
+       siginfo_t info;
+       void __user *pc = (void __user *)instruction_pointer(regs);
        console_verbose();
 
        pr_crit("Bad mode in %s handler detected, code 0x%08x\n",
                handler[reason], esr);
+       __show_regs(regs);
+
+       info.si_signo = SIGILL;
+       info.si_errno = 0;
+       info.si_code  = ILL_ILLOPC;
+       info.si_addr  = pc;
 
-       die("Oops - bad mode", regs, 0);
-       local_irq_disable();
-       panic("bad mode");
+       arm64_notify_die("Oops - bad mode", regs, &info, 0);
 }
 
 void __pte_error(const char *file, int line, unsigned long val)

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 98af6e760cce6781a5b117d786bcd16fc136a0b1..1426468b77f3bb7b6df96d604851449db13ed0da 100644 (file)
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -113,7 +113,8 @@ static void __do_user_fault(struct task_struct *tsk, unsigned long addr,
 {
        struct siginfo si;
 
-       if (show_unhandled_signals) {
+       if (show_unhandled_signals && unhandled_signal(tsk, sig) &&
+           printk_ratelimit()) {
                pr_info("%s[%d]: unhandled %s (%d) at 0x%08lx, esr 0x%03x\n",
                        tsk->comm, task_pid_nr(tsk), fault_name(esr), sig,
                        addr, esr);