Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index e6db475..4bb0f84 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -111,6 +111,7 @@
/* This code is a bit fragile. Test it. */
RCU_LOCKDEP_WARN(!rcu_is_watching(), "ist_enter didn't work");
}
+NOKPROBE_SYMBOL(ist_enter);
void ist_exit(struct pt_regs *regs)
{
@@ -189,7 +190,7 @@
}
static nokprobe_inline int
-do_trap_no_signal(struct task_struct *tsk, int trapnr, char *str,
+do_trap_no_signal(struct task_struct *tsk, int trapnr, const char *str,
struct pt_regs *regs, long error_code)
{
if (v8086_mode(regs)) {
@@ -202,11 +203,8 @@
error_code, trapnr))
return 0;
}
- return -1;
- }
-
- if (!user_mode(regs)) {
- if (fixup_exception(regs, trapnr))
+ } else if (!user_mode(regs)) {
+ if (fixup_exception(regs, trapnr, error_code, 0))
return 0;
tsk->thread.error_code = error_code;
@@ -214,49 +212,6 @@
die(str, regs, error_code);
}
- return -1;
-}
-
-static siginfo_t *fill_trap_info(struct pt_regs *regs, int signr, int trapnr,
- siginfo_t *info)
-{
- unsigned long siaddr;
- int sicode;
-
- switch (trapnr) {
- default:
- return SEND_SIG_PRIV;
-
- case X86_TRAP_DE:
- sicode = FPE_INTDIV;
- siaddr = uprobe_get_trap_addr(regs);
- break;
- case X86_TRAP_UD:
- sicode = ILL_ILLOPN;
- siaddr = uprobe_get_trap_addr(regs);
- break;
- case X86_TRAP_AC:
- sicode = BUS_ADRALN;
- siaddr = 0;
- break;
- }
-
- info->si_signo = signr;
- info->si_errno = 0;
- info->si_code = sicode;
- info->si_addr = (void __user *)siaddr;
- return info;
-}
-
-static void
-do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
- long error_code, siginfo_t *info)
-{
- struct task_struct *tsk = current;
-
-
- if (!do_trap_no_signal(tsk, trapnr, str, regs, error_code))
- return;
/*
* We want error_code and trap_nr set for userspace faults and
* kernelspace faults which result in die(), but not
@@ -269,24 +224,45 @@
tsk->thread.error_code = error_code;
tsk->thread.trap_nr = trapnr;
+ return -1;
+}
+
+static void show_signal(struct task_struct *tsk, int signr,
+ const char *type, const char *desc,
+ struct pt_regs *regs, long error_code)
+{
if (show_unhandled_signals && unhandled_signal(tsk, signr) &&
printk_ratelimit()) {
- pr_info("%s[%d] trap %s ip:%lx sp:%lx error:%lx",
- tsk->comm, tsk->pid, str,
+ pr_info("%s[%d] %s%s ip:%lx sp:%lx error:%lx",
+ tsk->comm, task_pid_nr(tsk), type, desc,
regs->ip, regs->sp, error_code);
print_vma_addr(KERN_CONT " in ", regs->ip);
pr_cont("\n");
}
+}
- force_sig_info(signr, info ?: SEND_SIG_PRIV, tsk);
+static void
+do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
+ long error_code, int sicode, void __user *addr)
+{
+ struct task_struct *tsk = current;
+
+
+ if (!do_trap_no_signal(tsk, trapnr, str, regs, error_code))
+ return;
+
+ show_signal(tsk, signr, "trap ", str, regs, error_code);
+
+ if (!sicode)
+ force_sig(signr);
+ else
+ force_sig_fault(signr, sicode, addr);
}
NOKPROBE_SYMBOL(do_trap);
static void do_error_trap(struct pt_regs *regs, long error_code, char *str,
- unsigned long trapnr, int signr)
+ unsigned long trapnr, int signr, int sicode, void __user *addr)
{
- siginfo_t info;
-
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
/*
@@ -299,26 +275,26 @@
if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) !=
NOTIFY_STOP) {
cond_local_irq_enable(regs);
- clear_siginfo(&info);
- do_trap(trapnr, signr, str, regs, error_code,
- fill_trap_info(regs, signr, trapnr, &info));
+ do_trap(trapnr, signr, str, regs, error_code, sicode, addr);
}
}
-#define DO_ERROR(trapnr, signr, str, name) \
-dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
-{ \
- do_error_trap(regs, error_code, str, trapnr, signr); \
+#define IP ((void __user *)uprobe_get_trap_addr(regs))
+#define DO_ERROR(trapnr, signr, sicode, addr, str, name) \
+dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
+{ \
+ do_error_trap(regs, error_code, str, trapnr, signr, sicode, addr); \
}
-DO_ERROR(X86_TRAP_DE, SIGFPE, "divide error", divide_error)
-DO_ERROR(X86_TRAP_OF, SIGSEGV, "overflow", overflow)
-DO_ERROR(X86_TRAP_UD, SIGILL, "invalid opcode", invalid_op)
-DO_ERROR(X86_TRAP_OLD_MF, SIGFPE, "coprocessor segment overrun",coprocessor_segment_overrun)
-DO_ERROR(X86_TRAP_TS, SIGSEGV, "invalid TSS", invalid_TSS)
-DO_ERROR(X86_TRAP_NP, SIGBUS, "segment not present", segment_not_present)
-DO_ERROR(X86_TRAP_SS, SIGBUS, "stack segment", stack_segment)
-DO_ERROR(X86_TRAP_AC, SIGBUS, "alignment check", alignment_check)
+DO_ERROR(X86_TRAP_DE, SIGFPE, FPE_INTDIV, IP, "divide error", divide_error)
+DO_ERROR(X86_TRAP_OF, SIGSEGV, 0, NULL, "overflow", overflow)
+DO_ERROR(X86_TRAP_UD, SIGILL, ILL_ILLOPN, IP, "invalid opcode", invalid_op)
+DO_ERROR(X86_TRAP_OLD_MF, SIGFPE, 0, NULL, "coprocessor segment overrun", coprocessor_segment_overrun)
+DO_ERROR(X86_TRAP_TS, SIGSEGV, 0, NULL, "invalid TSS", invalid_TSS)
+DO_ERROR(X86_TRAP_NP, SIGBUS, 0, NULL, "segment not present", segment_not_present)
+DO_ERROR(X86_TRAP_SS, SIGBUS, 0, NULL, "stack segment", stack_segment)
+DO_ERROR(X86_TRAP_AC, SIGBUS, BUS_ADRALN, NULL, "alignment check", alignment_check)
+#undef IP
#ifdef CONFIG_VMAP_STACK
__visible void __noreturn handle_stack_overflow(const char *message,
@@ -331,19 +307,16 @@
die(message, regs, 0);
/* Be absolutely certain we don't return. */
- panic(message);
+ panic("%s", message);
}
#endif
#ifdef CONFIG_X86_64
/* Runs on IST stack */
-dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
+dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsigned long cr2)
{
static const char str[] = "double fault";
struct task_struct *tsk = current;
-#ifdef CONFIG_VMAP_STACK
- unsigned long cr2;
-#endif
#ifdef CONFIG_X86_ESPFIX64
extern unsigned char native_irq_return_iret[];
@@ -383,6 +356,10 @@
* we won't enable interupts or schedule before we invoke
* general_protection, so nothing will clobber the stack
* frame we just set up.
+ *
+ * We will enter general_protection with kernel GSBASE,
+ * which is what the stub expects, given that the faulting
+ * RIP will be the IRET instruction.
*/
regs->ip = (unsigned long)general_protection;
regs->sp = (unsigned long)&gpregs->orig_ax;
@@ -435,7 +412,6 @@
* stack even if the actual trigger for the double fault was
* something else.
*/
- cr2 = read_cr2();
if ((unsigned long)task_stack_page(tsk) - 1 - cr2 < PAGE_SIZE)
handle_stack_overflow("kernel stack overflow (double-fault)", regs, cr2);
#endif
@@ -455,7 +431,6 @@
dotraplinkage void do_bounds(struct pt_regs *regs, long error_code)
{
const struct mpx_bndcsr *bndcsr;
- siginfo_t *info;
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
if (notify_die(DIE_TRAP, "bounds", regs, error_code,
@@ -477,7 +452,7 @@
* which is all zeros which indicates MPX was not
* responsible for the exception.
*/
- bndcsr = get_xsave_field_ptr(XFEATURE_MASK_BNDCSR);
+ bndcsr = get_xsave_field_ptr(XFEATURE_BNDCSR);
if (!bndcsr)
goto exit_trap;
@@ -493,8 +468,11 @@
goto exit_trap;
break; /* Success, it was handled */
case 1: /* Bound violation. */
- info = mpx_generate_siginfo(regs);
- if (IS_ERR(info)) {
+ {
+ struct task_struct *tsk = current;
+ struct mpx_fault_info mpx;
+
+ if (mpx_fault_info(&mpx, regs)) {
/*
* We failed to decode the MPX instruction. Act as if
* the exception was not caused by MPX.
@@ -503,14 +481,20 @@
}
/*
* Success, we decoded the instruction and retrieved
- * an 'info' containing the address being accessed
+ * an 'mpx' containing the address being accessed
* which caused the exception. This information
* allows and application to possibly handle the
* #BR exception itself.
*/
- do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, info);
- kfree(info);
+ if (!do_trap_no_signal(tsk, X86_TRAP_BR, "bounds", regs,
+ error_code))
+ break;
+
+ show_signal(tsk, SIGSEGV, "trap ", "bounds", regs, error_code);
+
+ force_sig_bnderr(mpx.addr, mpx.lower, mpx.upper);
break;
+ }
case 0: /* No exception caused by Intel MPX operations. */
goto exit_trap;
default:
@@ -527,12 +511,13 @@
* up here if the kernel has MPX turned off at compile
* time..
*/
- do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, NULL);
+ do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, 0, NULL);
}
dotraplinkage void
do_general_protection(struct pt_regs *regs, long error_code)
{
+ const char *desc = "general protection fault";
struct task_struct *tsk;
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
@@ -551,30 +536,33 @@
tsk = current;
if (!user_mode(regs)) {
- if (fixup_exception(regs, X86_TRAP_GP))
+ if (fixup_exception(regs, X86_TRAP_GP, error_code, 0))
return;
tsk->thread.error_code = error_code;
tsk->thread.trap_nr = X86_TRAP_GP;
- if (notify_die(DIE_GPF, "general protection fault", regs, error_code,
+
+ /*
+ * To be potentially processing a kprobe fault and to
+ * trust the result from kprobe_running(), we have to
+ * be non-preemptible.
+ */
+ if (!preemptible() && kprobe_running() &&
+ kprobe_fault_handler(regs, X86_TRAP_GP))
+ return;
+
+ if (notify_die(DIE_GPF, desc, regs, error_code,
X86_TRAP_GP, SIGSEGV) != NOTIFY_STOP)
- die("general protection fault", regs, error_code);
+ die(desc, regs, error_code);
return;
}
tsk->thread.error_code = error_code;
tsk->thread.trap_nr = X86_TRAP_GP;
- if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
- printk_ratelimit()) {
- pr_info("%s[%d] general protection ip:%lx sp:%lx error:%lx",
- tsk->comm, task_pid_nr(tsk),
- regs->ip, regs->sp, error_code);
- print_vma_addr(KERN_CONT " in ", regs->ip);
- pr_cont("\n");
- }
+ show_signal(tsk, SIGSEGV, "", desc, regs, error_code);
- force_sig_info(SIGSEGV, SEND_SIG_PRIV, tsk);
+ force_sig(SIGSEGV);
}
NOKPROBE_SYMBOL(do_general_protection);
@@ -617,7 +605,7 @@
goto exit;
cond_local_irq_enable(regs);
- do_trap(X86_TRAP_BP, SIGTRAP, "int3", regs, error_code, NULL);
+ do_trap(X86_TRAP_BP, SIGTRAP, "int3", regs, error_code, 0, NULL);
cond_local_irq_disable(regs);
exit:
@@ -813,7 +801,7 @@
}
si_code = get_si_code(tsk->thread.debugreg6);
if (tsk->thread.debugreg6 & (DR_STEP | DR_TRAP_BITS) || user_icebp)
- send_sigtrap(tsk, regs, error_code, si_code);
+ send_sigtrap(regs, error_code, si_code);
cond_local_irq_disable(regs);
debug_stack_usage_dec();
@@ -831,14 +819,14 @@
{
struct task_struct *task = current;
struct fpu *fpu = &task->thread.fpu;
- siginfo_t info;
+ int si_code;
char *str = (trapnr == X86_TRAP_MF) ? "fpu exception" :
"simd exception";
cond_local_irq_enable(regs);
if (!user_mode(regs)) {
- if (fixup_exception(regs, trapnr))
+ if (fixup_exception(regs, trapnr, error_code, 0))
return;
task->thread.error_code = error_code;
@@ -857,18 +845,14 @@
task->thread.trap_nr = trapnr;
task->thread.error_code = error_code;
- clear_siginfo(&info);
- info.si_signo = SIGFPE;
- info.si_errno = 0;
- info.si_addr = (void __user *)uprobe_get_trap_addr(regs);
- info.si_code = fpu__exception_code(fpu, trapnr);
-
+ si_code = fpu__exception_code(fpu, trapnr);
/* Retry when we get spurious exceptions: */
- if (!info.si_code)
+ if (!si_code)
return;
- force_sig_info(SIGFPE, &info, task);
+ force_sig_fault(SIGFPE, si_code,
+ (void __user *)uprobe_get_trap_addr(regs));
}
dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
@@ -893,12 +877,12 @@
dotraplinkage void
do_device_not_available(struct pt_regs *regs, long error_code)
{
- unsigned long cr0;
+ unsigned long cr0 = read_cr0();
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
#ifdef CONFIG_MATH_EMULATION
- if (!boot_cpu_has(X86_FEATURE_FPU) && (read_cr0() & X86_CR0_EM)) {
+ if (!boot_cpu_has(X86_FEATURE_FPU) && (cr0 & X86_CR0_EM)) {
struct math_emu_info info = { };
cond_local_irq_enable(regs);
@@ -910,7 +894,6 @@
#endif
/* This should not happen. */
- cr0 = read_cr0();
if (WARN(cr0 & X86_CR0_TS, "CR0.TS was set")) {
/* Try to fix it up and carry on. */
write_cr0(cr0 & ~X86_CR0_TS);
@@ -928,20 +911,13 @@
#ifdef CONFIG_X86_32
dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
{
- siginfo_t info;
-
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
local_irq_enable();
- clear_siginfo(&info);
- info.si_signo = SIGILL;
- info.si_errno = 0;
- info.si_code = ILL_BADSTK;
- info.si_addr = NULL;
if (notify_die(DIE_TRAP, "iret exception", regs, error_code,
X86_TRAP_IRET, SIGILL) != NOTIFY_STOP) {
do_trap(X86_TRAP_IRET, SIGILL, "iret exception", regs, error_code,
- &info);
+ ILL_BADSTK, (void __user *)NULL);
}
}
#endif