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Diffstat (limited to 'kernel/arch/arm64/mm/fault.c')
-rw-r--r--kernel/arch/arm64/mm/fault.c69
1 files changed, 50 insertions, 19 deletions
diff --git a/kernel/arch/arm64/mm/fault.c b/kernel/arch/arm64/mm/fault.c
index 0948d327d..92ddac1e8 100644
--- a/kernel/arch/arm64/mm/fault.c
+++ b/kernel/arch/arm64/mm/fault.c
@@ -30,9 +30,11 @@
#include <linux/highmem.h>
#include <linux/perf_event.h>
+#include <asm/cpufeature.h>
#include <asm/exception.h>
#include <asm/debug-monitors.h>
#include <asm/esr.h>
+#include <asm/sysreg.h>
#include <asm/system_misc.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
@@ -115,8 +117,7 @@ static void __do_user_fault(struct task_struct *tsk, unsigned long addr,
{
struct siginfo si;
- if (show_unhandled_signals && unhandled_signal(tsk, sig) &&
- printk_ratelimit()) {
+ if (unhandled_signal(tsk, sig) && show_unhandled_signals_ratelimited()) {
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);
@@ -225,6 +226,13 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
}
/*
+ * PAN bit set implies the fault happened in kernel space, but not
+ * in the arch's user access functions.
+ */
+ if (IS_ENABLED(CONFIG_ARM64_PAN) && (regs->pstate & PSR_PAN_BIT))
+ goto no_context;
+
+ /*
* As per x86, we may deadlock here. However, since the kernel only
* validly references user space from well defined areas of the code,
* we can bug out early if this is from code which shouldn't.
@@ -279,6 +287,7 @@ retry:
* starvation.
*/
mm_flags &= ~FAULT_FLAG_ALLOW_RETRY;
+ mm_flags |= FAULT_FLAG_TRIED;
goto retry;
}
}
@@ -384,16 +393,16 @@ static struct fault_info {
{ do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 1 translation fault" },
{ do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 2 translation fault" },
{ do_page_fault, SIGSEGV, SEGV_MAPERR, "level 3 translation fault" },
- { do_bad, SIGBUS, 0, "reserved access flag fault" },
+ { do_bad, SIGBUS, 0, "unknown 8" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 1 access flag fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 2 access flag fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 3 access flag fault" },
- { do_bad, SIGBUS, 0, "reserved permission fault" },
+ { do_bad, SIGBUS, 0, "unknown 12" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 1 permission fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 2 permission fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 3 permission fault" },
{ do_bad, SIGBUS, 0, "synchronous external abort" },
- { do_bad, SIGBUS, 0, "asynchronous external abort" },
+ { do_bad, SIGBUS, 0, "unknown 17" },
{ do_bad, SIGBUS, 0, "unknown 18" },
{ do_bad, SIGBUS, 0, "unknown 19" },
{ do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" },
@@ -401,16 +410,16 @@ static struct fault_info {
{ do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" },
{ do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" },
{ do_bad, SIGBUS, 0, "synchronous parity error" },
- { do_bad, SIGBUS, 0, "asynchronous parity error" },
+ { do_bad, SIGBUS, 0, "unknown 25" },
{ do_bad, SIGBUS, 0, "unknown 26" },
{ do_bad, SIGBUS, 0, "unknown 27" },
- { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" },
- { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" },
- { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" },
- { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" },
+ { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk)" },
+ { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk)" },
+ { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk)" },
+ { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk)" },
{ do_bad, SIGBUS, 0, "unknown 32" },
{ do_bad, SIGBUS, BUS_ADRALN, "alignment fault" },
- { do_bad, SIGBUS, 0, "debug event" },
+ { do_bad, SIGBUS, 0, "unknown 34" },
{ do_bad, SIGBUS, 0, "unknown 35" },
{ do_bad, SIGBUS, 0, "unknown 36" },
{ do_bad, SIGBUS, 0, "unknown 37" },
@@ -424,21 +433,21 @@ static struct fault_info {
{ do_bad, SIGBUS, 0, "unknown 45" },
{ do_bad, SIGBUS, 0, "unknown 46" },
{ do_bad, SIGBUS, 0, "unknown 47" },
- { do_bad, SIGBUS, 0, "unknown 48" },
+ { do_bad, SIGBUS, 0, "TLB conflict abort" },
{ do_bad, SIGBUS, 0, "unknown 49" },
{ do_bad, SIGBUS, 0, "unknown 50" },
{ do_bad, SIGBUS, 0, "unknown 51" },
{ do_bad, SIGBUS, 0, "implementation fault (lockdown abort)" },
- { do_bad, SIGBUS, 0, "unknown 53" },
+ { do_bad, SIGBUS, 0, "implementation fault (unsupported exclusive)" },
{ do_bad, SIGBUS, 0, "unknown 54" },
{ do_bad, SIGBUS, 0, "unknown 55" },
{ do_bad, SIGBUS, 0, "unknown 56" },
{ do_bad, SIGBUS, 0, "unknown 57" },
- { do_bad, SIGBUS, 0, "implementation fault (coprocessor abort)" },
+ { do_bad, SIGBUS, 0, "unknown 58" },
{ do_bad, SIGBUS, 0, "unknown 59" },
{ do_bad, SIGBUS, 0, "unknown 60" },
- { do_bad, SIGBUS, 0, "unknown 61" },
- { do_bad, SIGBUS, 0, "unknown 62" },
+ { do_bad, SIGBUS, 0, "section domain fault" },
+ { do_bad, SIGBUS, 0, "page domain fault" },
{ do_bad, SIGBUS, 0, "unknown 63" },
};
@@ -478,22 +487,37 @@ asmlinkage void __exception do_sp_pc_abort(unsigned long addr,
struct pt_regs *regs)
{
struct siginfo info;
+ struct task_struct *tsk = current;
+
+ if (show_unhandled_signals && unhandled_signal(tsk, SIGBUS))
+ pr_info_ratelimited("%s[%d]: %s exception: pc=%p sp=%p\n",
+ tsk->comm, task_pid_nr(tsk),
+ esr_get_class_string(esr), (void *)regs->pc,
+ (void *)regs->sp);
info.si_signo = SIGBUS;
info.si_errno = 0;
info.si_code = BUS_ADRALN;
info.si_addr = (void __user *)addr;
- arm64_notify_die("", regs, &info, esr);
+ arm64_notify_die("Oops - SP/PC alignment exception", regs, &info, esr);
}
-static struct fault_info debug_fault_info[] = {
+int __init early_brk64(unsigned long addr, unsigned int esr,
+ struct pt_regs *regs);
+
+/*
+ * __refdata because early_brk64 is __init, but the reference to it is
+ * clobbered at arch_initcall time.
+ * See traps.c and debug-monitors.c:debug_traps_init().
+ */
+static struct fault_info __refdata debug_fault_info[] = {
{ do_bad, SIGTRAP, TRAP_HWBKPT, "hardware breakpoint" },
{ do_bad, SIGTRAP, TRAP_HWBKPT, "hardware single-step" },
{ do_bad, SIGTRAP, TRAP_HWBKPT, "hardware watchpoint" },
{ do_bad, SIGBUS, 0, "unknown 3" },
{ do_bad, SIGTRAP, TRAP_BRKPT, "aarch32 BKPT" },
{ do_bad, SIGTRAP, 0, "aarch32 vector catch" },
- { do_bad, SIGTRAP, TRAP_BRKPT, "aarch64 BRK" },
+ { early_brk64, SIGTRAP, TRAP_BRKPT, "aarch64 BRK" },
{ do_bad, SIGBUS, 0, "unknown 7" },
};
@@ -530,3 +554,10 @@ asmlinkage int __exception do_debug_exception(unsigned long addr,
return 0;
}
+
+#ifdef CONFIG_ARM64_PAN
+void cpu_enable_pan(void *__unused)
+{
+ config_sctlr_el1(SCTLR_EL1_SPAN, 0);
+}
+#endif /* CONFIG_ARM64_PAN */