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-rw-r--r--arch/arm64/kernel/traps.c169
1 files changed, 110 insertions, 59 deletions
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index e8986e6067a9..23d281ed7621 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -9,7 +9,6 @@
#include <linux/bug.h>
#include <linux/context_tracking.h>
#include <linux/signal.h>
-#include <linux/personality.h>
#include <linux/kallsyms.h>
#include <linux/kprobes.h>
#include <linux/spinlock.h>
@@ -27,6 +26,7 @@
#include <linux/syscalls.h>
#include <linux/mm_types.h>
#include <linux/kasan.h>
+#include <linux/cfi.h>
#include <asm/atomic.h>
#include <asm/bug.h>
@@ -181,12 +181,12 @@ static void dump_kernel_instr(const char *lvl, struct pt_regs *regs)
#define S_SMP " SMP"
-static int __die(const char *str, int err, struct pt_regs *regs)
+static int __die(const char *str, long err, struct pt_regs *regs)
{
static int die_counter;
int ret;
- pr_emerg("Internal error: %s: %x [#%d]" S_PREEMPT S_SMP "\n",
+ pr_emerg("Internal error: %s: %016lx [#%d]" S_PREEMPT S_SMP "\n",
str, err, ++die_counter);
/* trap and error numbers are mostly meaningless on ARM */
@@ -207,7 +207,7 @@ static DEFINE_RAW_SPINLOCK(die_lock);
/*
* This function is protected against re-entrancy.
*/
-void die(const char *str, struct pt_regs *regs, int err)
+void die(const char *str, struct pt_regs *regs, long err)
{
int ret;
unsigned long flags;
@@ -235,7 +235,7 @@ void die(const char *str, struct pt_regs *regs, int err)
raw_spin_unlock_irqrestore(&die_lock, flags);
if (ret != NOTIFY_STOP)
- do_exit(SIGSEGV);
+ make_task_dead(SIGSEGV);
}
static void arm64_show_signal(int signo, const char *str)
@@ -243,7 +243,7 @@ static void arm64_show_signal(int signo, const char *str)
static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
DEFAULT_RATELIMIT_BURST);
struct task_struct *tsk = current;
- unsigned int esr = tsk->thread.fault_code;
+ unsigned long esr = tsk->thread.fault_code;
struct pt_regs *regs = task_pt_regs(tsk);
/* Leave if the signal won't be shown */
@@ -254,7 +254,7 @@ static void arm64_show_signal(int signo, const char *str)
pr_info("%s[%d]: unhandled exception: ", tsk->comm, task_pid_nr(tsk));
if (esr)
- pr_cont("%s, ESR 0x%08x, ", esr_get_class_string(esr), esr);
+ pr_cont("%s, ESR 0x%016lx, ", esr_get_class_string(esr), esr);
pr_cont("%s", str);
print_vma_addr(KERN_CONT " in ", regs->pc);
@@ -288,7 +288,7 @@ void arm64_force_sig_ptrace_errno_trap(int errno, unsigned long far,
void arm64_notify_die(const char *str, struct pt_regs *regs,
int signo, int sicode, unsigned long far,
- int err)
+ unsigned long err)
{
if (user_mode(regs)) {
WARN_ON(regs != current_pt_regs());
@@ -440,7 +440,7 @@ exit:
return fn ? fn(regs, instr) : 1;
}
-void force_signal_inject(int signal, int code, unsigned long address, unsigned int err)
+void force_signal_inject(int signal, int code, unsigned long address, unsigned long err)
{
const char *desc;
struct pt_regs *regs = current_pt_regs();
@@ -486,7 +486,7 @@ void arm64_notify_segfault(unsigned long addr)
force_signal_inject(SIGSEGV, code, addr, 0);
}
-void do_undefinstr(struct pt_regs *regs)
+void do_undefinstr(struct pt_regs *regs, unsigned long esr)
{
/* check for AArch32 breakpoint instructions */
if (!aarch32_break_handler(regs))
@@ -495,31 +495,41 @@ void do_undefinstr(struct pt_regs *regs)
if (call_undef_hook(regs) == 0)
return;
- BUG_ON(!user_mode(regs));
+ if (!user_mode(regs))
+ die("Oops - Undefined instruction", regs, esr);
+
force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
}
NOKPROBE_SYMBOL(do_undefinstr);
-void do_bti(struct pt_regs *regs)
+void do_el0_bti(struct pt_regs *regs)
{
- BUG_ON(!user_mode(regs));
force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
}
-NOKPROBE_SYMBOL(do_bti);
-void do_ptrauth_fault(struct pt_regs *regs, unsigned int esr)
+void do_el1_bti(struct pt_regs *regs, unsigned long esr)
+{
+ die("Oops - BTI", regs, esr);
+}
+NOKPROBE_SYMBOL(do_el1_bti);
+
+void do_el0_fpac(struct pt_regs *regs, unsigned long esr)
+{
+ force_signal_inject(SIGILL, ILL_ILLOPN, regs->pc, esr);
+}
+
+void do_el1_fpac(struct pt_regs *regs, unsigned long esr)
{
/*
- * Unexpected FPAC exception or pointer authentication failure in
- * the kernel: kill the task before it does any more harm.
+ * Unexpected FPAC exception in the kernel: kill the task before it
+ * does any more harm.
*/
- BUG_ON(!user_mode(regs));
- force_signal_inject(SIGILL, ILL_ILLOPN, regs->pc, esr);
+ die("Oops - FPAC", regs, esr);
}
-NOKPROBE_SYMBOL(do_ptrauth_fault);
+NOKPROBE_SYMBOL(do_el1_fpac)
#define __user_cache_maint(insn, address, res) \
- if (address >= user_addr_max()) { \
+ if (address >= TASK_SIZE_MAX) { \
res = -EFAULT; \
} else { \
uaccess_ttbr0_enable(); \
@@ -533,7 +543,7 @@ NOKPROBE_SYMBOL(do_ptrauth_fault);
uaccess_ttbr0_disable(); \
}
-static void user_cache_maint_handler(unsigned int esr, struct pt_regs *regs)
+static void user_cache_maint_handler(unsigned long esr, struct pt_regs *regs)
{
unsigned long tagged_address, address;
int rt = ESR_ELx_SYS64_ISS_RT(esr);
@@ -573,18 +583,18 @@ static void user_cache_maint_handler(unsigned int esr, struct pt_regs *regs)
arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
}
-static void ctr_read_handler(unsigned int esr, struct pt_regs *regs)
+static void ctr_read_handler(unsigned long esr, struct pt_regs *regs)
{
int rt = ESR_ELx_SYS64_ISS_RT(esr);
unsigned long val = arm64_ftr_reg_user_value(&arm64_ftr_reg_ctrel0);
if (cpus_have_const_cap(ARM64_WORKAROUND_1542419)) {
/* Hide DIC so that we can trap the unnecessary maintenance...*/
- val &= ~BIT(CTR_DIC_SHIFT);
+ val &= ~BIT(CTR_EL0_DIC_SHIFT);
/* ... and fake IminLine to reduce the number of traps. */
- val &= ~CTR_IMINLINE_MASK;
- val |= (PAGE_SHIFT - 2) & CTR_IMINLINE_MASK;
+ val &= ~CTR_EL0_IminLine_MASK;
+ val |= (PAGE_SHIFT - 2) & CTR_EL0_IminLine_MASK;
}
pt_regs_write_reg(regs, rt, val);
@@ -592,7 +602,7 @@ static void ctr_read_handler(unsigned int esr, struct pt_regs *regs)
arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
}
-static void cntvct_read_handler(unsigned int esr, struct pt_regs *regs)
+static void cntvct_read_handler(unsigned long esr, struct pt_regs *regs)
{
int rt = ESR_ELx_SYS64_ISS_RT(esr);
@@ -600,7 +610,7 @@ static void cntvct_read_handler(unsigned int esr, struct pt_regs *regs)
arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
}
-static void cntfrq_read_handler(unsigned int esr, struct pt_regs *regs)
+static void cntfrq_read_handler(unsigned long esr, struct pt_regs *regs)
{
int rt = ESR_ELx_SYS64_ISS_RT(esr);
@@ -608,7 +618,7 @@ static void cntfrq_read_handler(unsigned int esr, struct pt_regs *regs)
arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
}
-static void mrs_handler(unsigned int esr, struct pt_regs *regs)
+static void mrs_handler(unsigned long esr, struct pt_regs *regs)
{
u32 sysreg, rt;
@@ -619,15 +629,15 @@ static void mrs_handler(unsigned int esr, struct pt_regs *regs)
force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
}
-static void wfi_handler(unsigned int esr, struct pt_regs *regs)
+static void wfi_handler(unsigned long esr, struct pt_regs *regs)
{
arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
}
struct sys64_hook {
- unsigned int esr_mask;
- unsigned int esr_val;
- void (*handler)(unsigned int esr, struct pt_regs *regs);
+ unsigned long esr_mask;
+ unsigned long esr_val;
+ void (*handler)(unsigned long esr, struct pt_regs *regs);
};
static const struct sys64_hook sys64_hooks[] = {
@@ -676,7 +686,7 @@ static const struct sys64_hook sys64_hooks[] = {
};
#ifdef CONFIG_COMPAT
-static bool cp15_cond_valid(unsigned int esr, struct pt_regs *regs)
+static bool cp15_cond_valid(unsigned long esr, struct pt_regs *regs)
{
int cond;
@@ -696,7 +706,7 @@ static bool cp15_cond_valid(unsigned int esr, struct pt_regs *regs)
return aarch32_opcode_cond_checks[cond](regs->pstate);
}
-static void compat_cntfrq_read_handler(unsigned int esr, struct pt_regs *regs)
+static void compat_cntfrq_read_handler(unsigned long esr, struct pt_regs *regs)
{
int reg = (esr & ESR_ELx_CP15_32_ISS_RT_MASK) >> ESR_ELx_CP15_32_ISS_RT_SHIFT;
@@ -713,7 +723,7 @@ static const struct sys64_hook cp15_32_hooks[] = {
{},
};
-static void compat_cntvct_read_handler(unsigned int esr, struct pt_regs *regs)
+static void compat_cntvct_read_handler(unsigned long esr, struct pt_regs *regs)
{
int rt = (esr & ESR_ELx_CP15_64_ISS_RT_MASK) >> ESR_ELx_CP15_64_ISS_RT_SHIFT;
int rt2 = (esr & ESR_ELx_CP15_64_ISS_RT2_MASK) >> ESR_ELx_CP15_64_ISS_RT2_SHIFT;
@@ -738,7 +748,7 @@ static const struct sys64_hook cp15_64_hooks[] = {
{},
};
-void do_cp15instr(unsigned int esr, struct pt_regs *regs)
+void do_cp15instr(unsigned long esr, struct pt_regs *regs)
{
const struct sys64_hook *hook, *hook_base;
@@ -759,7 +769,7 @@ void do_cp15instr(unsigned int esr, struct pt_regs *regs)
hook_base = cp15_64_hooks;
break;
default:
- do_undefinstr(regs);
+ do_undefinstr(regs, esr);
return;
}
@@ -774,12 +784,12 @@ void do_cp15instr(unsigned int esr, struct pt_regs *regs)
* EL0. Fall back to our usual undefined instruction handler
* so that we handle these consistently.
*/
- do_undefinstr(regs);
+ do_undefinstr(regs, esr);
}
NOKPROBE_SYMBOL(do_cp15instr);
#endif
-void do_sysinstr(unsigned int esr, struct pt_regs *regs)
+void do_sysinstr(unsigned long esr, struct pt_regs *regs)
{
const struct sys64_hook *hook;
@@ -794,7 +804,7 @@ void do_sysinstr(unsigned int esr, struct pt_regs *regs)
* back to our usual undefined instruction handler so that we handle
* these consistently.
*/
- do_undefinstr(regs);
+ do_undefinstr(regs, esr);
}
NOKPROBE_SYMBOL(do_sysinstr);
@@ -822,6 +832,7 @@ static const char *esr_class_str[] = {
[ESR_ELx_EC_SVE] = "SVE",
[ESR_ELx_EC_ERET] = "ERET/ERETAA/ERETAB",
[ESR_ELx_EC_FPAC] = "FPAC",
+ [ESR_ELx_EC_SME] = "SME",
[ESR_ELx_EC_IMP_DEF] = "EL3 IMP DEF",
[ESR_ELx_EC_IABT_LOW] = "IABT (lower EL)",
[ESR_ELx_EC_IABT_CUR] = "IABT (current EL)",
@@ -843,7 +854,7 @@ static const char *esr_class_str[] = {
[ESR_ELx_EC_BRK64] = "BRK (AArch64)",
};
-const char *esr_get_class_string(u32 esr)
+const char *esr_get_class_string(unsigned long esr)
{
return esr_class_str[ESR_ELx_EC(esr)];
}
@@ -852,7 +863,7 @@ const char *esr_get_class_string(u32 esr)
* bad_el0_sync handles unexpected, but potentially recoverable synchronous
* exceptions taken from EL0.
*/
-void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr)
+void bad_el0_sync(struct pt_regs *regs, int reason, unsigned long esr)
{
unsigned long pc = instruction_pointer(regs);
@@ -868,7 +879,7 @@ void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr)
DEFINE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeof(long)], overflow_stack)
__aligned(16);
-void panic_bad_stack(struct pt_regs *regs, unsigned int esr, unsigned long far)
+void panic_bad_stack(struct pt_regs *regs, unsigned long esr, unsigned long far)
{
unsigned long tsk_stk = (unsigned long)current->stack;
unsigned long irq_stk = (unsigned long)this_cpu_read(irq_stack_ptr);
@@ -877,7 +888,7 @@ void panic_bad_stack(struct pt_regs *regs, unsigned int esr, unsigned long far)
console_verbose();
pr_emerg("Insufficient stack space to handle exception!");
- pr_emerg("ESR: 0x%08x -- %s\n", esr, esr_get_class_string(esr));
+ pr_emerg("ESR: 0x%016lx -- %s\n", esr, esr_get_class_string(esr));
pr_emerg("FAR: 0x%016lx\n", far);
pr_emerg("Task stack: [0x%016lx..0x%016lx]\n",
@@ -898,11 +909,11 @@ void panic_bad_stack(struct pt_regs *regs, unsigned int esr, unsigned long far)
}
#endif
-void __noreturn arm64_serror_panic(struct pt_regs *regs, u32 esr)
+void __noreturn arm64_serror_panic(struct pt_regs *regs, unsigned long esr)
{
console_verbose();
- pr_crit("SError Interrupt on CPU%d, code 0x%08x -- %s\n",
+ pr_crit("SError Interrupt on CPU%d, code 0x%016lx -- %s\n",
smp_processor_id(), esr, esr_get_class_string(esr));
if (regs)
__show_regs(regs);
@@ -913,9 +924,9 @@ void __noreturn arm64_serror_panic(struct pt_regs *regs, u32 esr)
unreachable();
}
-bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr)
+bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned long esr)
{
- u32 aet = arm64_ras_serror_get_severity(esr);
+ unsigned long aet = arm64_ras_serror_get_severity(esr);
switch (aet) {
case ESR_ELx_AET_CE: /* corrected error */
@@ -945,7 +956,7 @@ bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr)
}
}
-void do_serror(struct pt_regs *regs, unsigned int esr)
+void do_serror(struct pt_regs *regs, unsigned long esr)
{
/* non-RAS errors are not containable */
if (!arm64_is_ras_serror(esr) || arm64_is_fatal_ras_serror(regs, esr))
@@ -966,11 +977,11 @@ int is_valid_bugaddr(unsigned long addr)
return 1;
}
-static int bug_handler(struct pt_regs *regs, unsigned int esr)
+static int bug_handler(struct pt_regs *regs, unsigned long esr)
{
switch (report_bug(regs->pc, regs)) {
case BUG_TRAP_TYPE_BUG:
- die("Oops - BUG", regs, 0);
+ die("Oops - BUG", regs, esr);
break;
case BUG_TRAP_TYPE_WARN:
@@ -991,7 +1002,39 @@ static struct break_hook bug_break_hook = {
.imm = BUG_BRK_IMM,
};
-static int reserved_fault_handler(struct pt_regs *regs, unsigned int esr)
+#ifdef CONFIG_CFI_CLANG
+static int cfi_handler(struct pt_regs *regs, unsigned long esr)
+{
+ unsigned long target;
+ u32 type;
+
+ target = pt_regs_read_reg(regs, FIELD_GET(CFI_BRK_IMM_TARGET, esr));
+ type = (u32)pt_regs_read_reg(regs, FIELD_GET(CFI_BRK_IMM_TYPE, esr));
+
+ switch (report_cfi_failure(regs, regs->pc, &target, type)) {
+ case BUG_TRAP_TYPE_BUG:
+ die("Oops - CFI", regs, 0);
+ break;
+
+ case BUG_TRAP_TYPE_WARN:
+ break;
+
+ default:
+ return DBG_HOOK_ERROR;
+ }
+
+ arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
+ return DBG_HOOK_HANDLED;
+}
+
+static struct break_hook cfi_break_hook = {
+ .fn = cfi_handler,
+ .imm = CFI_BRK_IMM_BASE,
+ .mask = CFI_BRK_IMM_MASK,
+};
+#endif /* CONFIG_CFI_CLANG */
+
+static int reserved_fault_handler(struct pt_regs *regs, unsigned long esr)
{
pr_err("%s generated an invalid instruction at %pS!\n",
"Kernel text patching",
@@ -1013,7 +1056,7 @@ static struct break_hook fault_break_hook = {
#define KASAN_ESR_SIZE_MASK 0x0f
#define KASAN_ESR_SIZE(esr) (1 << ((esr) & KASAN_ESR_SIZE_MASK))
-static int kasan_handler(struct pt_regs *regs, unsigned int esr)
+static int kasan_handler(struct pt_regs *regs, unsigned long esr)
{
bool recover = esr & KASAN_ESR_RECOVER;
bool write = esr & KASAN_ESR_WRITE;
@@ -1038,7 +1081,7 @@ static int kasan_handler(struct pt_regs *regs, unsigned int esr)
* This is something that might be fixed at some point in the future.
*/
if (!recover)
- die("Oops - KASAN", regs, 0);
+ die("Oops - KASAN", regs, esr);
/* If thread survives, skip over the brk instruction and continue: */
arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
@@ -1052,17 +1095,22 @@ static struct break_hook kasan_break_hook = {
};
#endif
+
+#define esr_comment(esr) ((esr) & ESR_ELx_BRK64_ISS_COMMENT_MASK)
+
/*
* Initial handler for AArch64 BRK exceptions
* This handler only used until debug_traps_init().
*/
-int __init early_brk64(unsigned long addr, unsigned int esr,
+int __init early_brk64(unsigned long addr, unsigned long esr,
struct pt_regs *regs)
{
+#ifdef CONFIG_CFI_CLANG
+ if ((esr_comment(esr) & ~CFI_BRK_IMM_MASK) == CFI_BRK_IMM_BASE)
+ return cfi_handler(regs, esr) != DBG_HOOK_HANDLED;
+#endif
#ifdef CONFIG_KASAN_SW_TAGS
- unsigned int comment = esr & ESR_ELx_BRK64_ISS_COMMENT_MASK;
-
- if ((comment & ~KASAN_BRK_MASK) == KASAN_BRK_IMM)
+ if ((esr_comment(esr) & ~KASAN_BRK_MASK) == KASAN_BRK_IMM)
return kasan_handler(regs, esr) != DBG_HOOK_HANDLED;
#endif
return bug_handler(regs, esr) != DBG_HOOK_HANDLED;
@@ -1071,6 +1119,9 @@ int __init early_brk64(unsigned long addr, unsigned int esr,
void __init trap_init(void)
{
register_kernel_break_hook(&bug_break_hook);
+#ifdef CONFIG_CFI_CLANG
+ register_kernel_break_hook(&cfi_break_hook);
+#endif
register_kernel_break_hook(&fault_break_hook);
#ifdef CONFIG_KASAN_SW_TAGS
register_kernel_break_hook(&kasan_break_hook);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.