aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/arch/arm64/kernel/traps.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/kernel/traps.c')
-rw-r--r--arch/arm64/kernel/traps.c141
1 files changed, 74 insertions, 67 deletions
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index cf402be5c573..d332590f5978 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -272,6 +272,61 @@ void arm64_notify_die(const char *str, struct pt_regs *regs,
}
}
+#ifdef CONFIG_COMPAT
+#define PSTATE_IT_1_0_SHIFT 25
+#define PSTATE_IT_1_0_MASK (0x3 << PSTATE_IT_1_0_SHIFT)
+#define PSTATE_IT_7_2_SHIFT 10
+#define PSTATE_IT_7_2_MASK (0x3f << PSTATE_IT_7_2_SHIFT)
+
+static u32 compat_get_it_state(struct pt_regs *regs)
+{
+ u32 it, pstate = regs->pstate;
+
+ it = (pstate & PSTATE_IT_1_0_MASK) >> PSTATE_IT_1_0_SHIFT;
+ it |= ((pstate & PSTATE_IT_7_2_MASK) >> PSTATE_IT_7_2_SHIFT) << 2;
+
+ return it;
+}
+
+static void compat_set_it_state(struct pt_regs *regs, u32 it)
+{
+ u32 pstate_it;
+
+ pstate_it = (it << PSTATE_IT_1_0_SHIFT) & PSTATE_IT_1_0_MASK;
+ pstate_it |= ((it >> 2) << PSTATE_IT_7_2_SHIFT) & PSTATE_IT_7_2_MASK;
+
+ regs->pstate &= ~PSR_AA32_IT_MASK;
+ regs->pstate |= pstate_it;
+}
+
+static void advance_itstate(struct pt_regs *regs)
+{
+ u32 it;
+
+ /* ARM mode */
+ if (!(regs->pstate & PSR_AA32_T_BIT) ||
+ !(regs->pstate & PSR_AA32_IT_MASK))
+ return;
+
+ it = compat_get_it_state(regs);
+
+ /*
+ * If this is the last instruction of the block, wipe the IT
+ * state. Otherwise advance it.
+ */
+ if (!(it & 7))
+ it = 0;
+ else
+ it = (it & 0xe0) | ((it << 1) & 0x1f);
+
+ compat_set_it_state(regs, it);
+}
+#else
+static void advance_itstate(struct pt_regs *regs)
+{
+}
+#endif
+
void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size)
{
regs->pc += size;
@@ -282,6 +337,11 @@ void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size)
*/
if (user_mode(regs))
user_fastforward_single_step(current);
+
+ if (compat_user_mode(regs))
+ advance_itstate(regs);
+ else
+ regs->pstate &= ~PSR_BTYPE_MASK;
}
static LIST_HEAD(undef_hook);
@@ -411,6 +471,13 @@ void do_undefinstr(struct pt_regs *regs)
}
NOKPROBE_SYMBOL(do_undefinstr);
+void do_bti(struct pt_regs *regs)
+{
+ BUG_ON(!user_mode(regs));
+ force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
+}
+NOKPROBE_SYMBOL(do_bti);
+
#define __user_cache_maint(insn, address, res) \
if (address >= user_addr_max()) { \
res = -EFAULT; \
@@ -566,34 +633,7 @@ static const struct sys64_hook sys64_hooks[] = {
{},
};
-
#ifdef CONFIG_COMPAT
-#define PSTATE_IT_1_0_SHIFT 25
-#define PSTATE_IT_1_0_MASK (0x3 << PSTATE_IT_1_0_SHIFT)
-#define PSTATE_IT_7_2_SHIFT 10
-#define PSTATE_IT_7_2_MASK (0x3f << PSTATE_IT_7_2_SHIFT)
-
-static u32 compat_get_it_state(struct pt_regs *regs)
-{
- u32 it, pstate = regs->pstate;
-
- it = (pstate & PSTATE_IT_1_0_MASK) >> PSTATE_IT_1_0_SHIFT;
- it |= ((pstate & PSTATE_IT_7_2_MASK) >> PSTATE_IT_7_2_SHIFT) << 2;
-
- return it;
-}
-
-static void compat_set_it_state(struct pt_regs *regs, u32 it)
-{
- u32 pstate_it;
-
- pstate_it = (it << PSTATE_IT_1_0_SHIFT) & PSTATE_IT_1_0_MASK;
- pstate_it |= ((it >> 2) << PSTATE_IT_7_2_SHIFT) & PSTATE_IT_7_2_MASK;
-
- regs->pstate &= ~PSR_AA32_IT_MASK;
- regs->pstate |= pstate_it;
-}
-
static bool cp15_cond_valid(unsigned int esr, struct pt_regs *regs)
{
int cond;
@@ -614,42 +654,12 @@ static bool cp15_cond_valid(unsigned int esr, struct pt_regs *regs)
return aarch32_opcode_cond_checks[cond](regs->pstate);
}
-static void advance_itstate(struct pt_regs *regs)
-{
- u32 it;
-
- /* ARM mode */
- if (!(regs->pstate & PSR_AA32_T_BIT) ||
- !(regs->pstate & PSR_AA32_IT_MASK))
- return;
-
- it = compat_get_it_state(regs);
-
- /*
- * If this is the last instruction of the block, wipe the IT
- * state. Otherwise advance it.
- */
- if (!(it & 7))
- it = 0;
- else
- it = (it & 0xe0) | ((it << 1) & 0x1f);
-
- compat_set_it_state(regs, it);
-}
-
-static void arm64_compat_skip_faulting_instruction(struct pt_regs *regs,
- unsigned int sz)
-{
- advance_itstate(regs);
- arm64_skip_faulting_instruction(regs, sz);
-}
-
static void compat_cntfrq_read_handler(unsigned int esr, struct pt_regs *regs)
{
int reg = (esr & ESR_ELx_CP15_32_ISS_RT_MASK) >> ESR_ELx_CP15_32_ISS_RT_SHIFT;
pt_regs_write_reg(regs, reg, arch_timer_get_rate());
- arm64_compat_skip_faulting_instruction(regs, 4);
+ arm64_skip_faulting_instruction(regs, 4);
}
static const struct sys64_hook cp15_32_hooks[] = {
@@ -669,7 +679,7 @@ static void compat_cntvct_read_handler(unsigned int esr, struct pt_regs *regs)
pt_regs_write_reg(regs, rt, lower_32_bits(val));
pt_regs_write_reg(regs, rt2, upper_32_bits(val));
- arm64_compat_skip_faulting_instruction(regs, 4);
+ arm64_skip_faulting_instruction(regs, 4);
}
static const struct sys64_hook cp15_64_hooks[] = {
@@ -690,7 +700,7 @@ void do_cp15instr(unsigned int esr, struct pt_regs *regs)
* There is no T16 variant of a CP access, so we
* always advance PC by 4 bytes.
*/
- arm64_compat_skip_faulting_instruction(regs, 4);
+ arm64_skip_faulting_instruction(regs, 4);
return;
}
@@ -753,6 +763,7 @@ static const char *esr_class_str[] = {
[ESR_ELx_EC_CP10_ID] = "CP10 MRC/VMRS",
[ESR_ELx_EC_PAC] = "PAC",
[ESR_ELx_EC_CP14_64] = "CP14 MCRR/MRRC",
+ [ESR_ELx_EC_BTI] = "BTI",
[ESR_ELx_EC_ILL] = "PSTATE.IL",
[ESR_ELx_EC_SVC32] = "SVC (AArch32)",
[ESR_ELx_EC_HVC32] = "HVC (AArch32)",
@@ -906,17 +917,13 @@ bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr)
asmlinkage void do_serror(struct pt_regs *regs, unsigned int esr)
{
- const bool was_in_nmi = in_nmi();
-
- if (!was_in_nmi)
- nmi_enter();
+ nmi_enter();
/* non-RAS errors are not containable */
if (!arm64_is_ras_serror(esr) || arm64_is_fatal_ras_serror(regs, esr))
arm64_serror_panic(regs, esr);
- if (!was_in_nmi)
- nmi_exit();
+ nmi_exit();
}
asmlinkage void enter_from_user_mode(void)
@@ -1047,11 +1054,11 @@ int __init early_brk64(unsigned long addr, unsigned int esr,
return bug_handler(regs, esr) != DBG_HOOK_HANDLED;
}
-/* This registration must happen early, before debug_traps_init(). */
void __init trap_init(void)
{
register_kernel_break_hook(&bug_break_hook);
#ifdef CONFIG_KASAN_SW_TAGS
register_kernel_break_hook(&kasan_break_hook);
#endif
+ debug_traps_init();
}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.