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Diffstat (limited to 'arch/arm64/mm/fault.c')
-rw-r--r--arch/arm64/mm/fault.c89
1 files changed, 44 insertions, 45 deletions
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 0f8788374815..1b35b8bddbfb 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -26,7 +26,8 @@
#include <linux/kprobes.h>
#include <linux/uaccess.h>
#include <linux/page-flags.h>
-#include <linux/sched.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/debug.h>
#include <linux/highmem.h>
#include <linux/perf_event.h>
#include <linux/preempt.h>
@@ -41,7 +42,20 @@
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
-static const char *fault_name(unsigned int esr);
+struct fault_info {
+ int (*fn)(unsigned long addr, unsigned int esr,
+ struct pt_regs *regs);
+ int sig;
+ int code;
+ const char *name;
+};
+
+static const struct fault_info fault_info[];
+
+static inline const struct fault_info *esr_to_fault_info(unsigned int esr)
+{
+ return fault_info + (esr & 63);
+}
#ifdef CONFIG_KPROBES
static inline int notify_page_fault(struct pt_regs *regs, unsigned int esr)
@@ -88,21 +102,21 @@ void show_pte(struct mm_struct *mm, unsigned long addr)
break;
pud = pud_offset(pgd, addr);
- printk(", *pud=%016llx", pud_val(*pud));
+ pr_cont(", *pud=%016llx", pud_val(*pud));
if (pud_none(*pud) || pud_bad(*pud))
break;
pmd = pmd_offset(pud, addr);
- printk(", *pmd=%016llx", pmd_val(*pmd));
+ pr_cont(", *pmd=%016llx", pmd_val(*pmd));
if (pmd_none(*pmd) || pmd_bad(*pmd))
break;
pte = pte_offset_map(pmd, addr);
- printk(", *pte=%016llx", pte_val(*pte));
+ pr_cont(", *pte=%016llx", pte_val(*pte));
pte_unmap(pte);
} while(0);
- printk("\n");
+ pr_cont("\n");
}
#ifdef CONFIG_ARM64_HW_AFDBM
@@ -196,10 +210,12 @@ static void __do_user_fault(struct task_struct *tsk, unsigned long addr,
struct pt_regs *regs)
{
struct siginfo si;
+ const struct fault_info *inf;
if (unhandled_signal(tsk, sig) && show_unhandled_signals_ratelimited()) {
+ inf = esr_to_fault_info(esr);
pr_info("%s[%d]: unhandled %s (%d) at 0x%08lx, esr 0x%03x\n",
- tsk->comm, task_pid_nr(tsk), fault_name(esr), sig,
+ tsk->comm, task_pid_nr(tsk), inf->name, sig,
addr, esr);
show_pte(tsk->mm, addr);
show_regs(regs);
@@ -218,14 +234,16 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re
{
struct task_struct *tsk = current;
struct mm_struct *mm = tsk->active_mm;
+ const struct fault_info *inf;
/*
* If we are in kernel mode at this point, we have no context to
* handle this fault with.
*/
- if (user_mode(regs))
- __do_user_fault(tsk, addr, esr, SIGSEGV, SEGV_MAPERR, regs);
- else
+ if (user_mode(regs)) {
+ inf = esr_to_fault_info(esr);
+ __do_user_fault(tsk, addr, esr, inf->sig, inf->code, regs);
+ } else
__do_kernel_fault(mm, addr, esr, regs);
}
@@ -269,13 +287,19 @@ out:
return fault;
}
-static inline bool is_permission_fault(unsigned int esr)
+static inline bool is_permission_fault(unsigned int esr, struct pt_regs *regs)
{
unsigned int ec = ESR_ELx_EC(esr);
unsigned int fsc_type = esr & ESR_ELx_FSC_TYPE;
- return (ec == ESR_ELx_EC_DABT_CUR && fsc_type == ESR_ELx_FSC_PERM) ||
- (ec == ESR_ELx_EC_IABT_CUR && fsc_type == ESR_ELx_FSC_PERM);
+ if (ec != ESR_ELx_EC_DABT_CUR && ec != ESR_ELx_EC_IABT_CUR)
+ return false;
+
+ if (system_uses_ttbr0_pan())
+ return fsc_type == ESR_ELx_FSC_FAULT &&
+ (regs->pstate & PSR_PAN_BIT);
+ else
+ return fsc_type == ESR_ELx_FSC_PERM;
}
static bool is_el0_instruction_abort(unsigned int esr)
@@ -315,7 +339,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
mm_flags |= FAULT_FLAG_WRITE;
}
- if (is_permission_fault(esr) && (addr < USER_DS)) {
+ if (addr < USER_DS && is_permission_fault(esr, regs)) {
/* regs->orig_addr_limit may be 0 if we entered from EL0 */
if (regs->orig_addr_limit == KERNEL_DS)
die("Accessing user space memory with fs=KERNEL_DS", regs, esr);
@@ -481,12 +505,7 @@ static int do_bad(unsigned long addr, unsigned int esr, struct pt_regs *regs)
return 1;
}
-static const struct fault_info {
- int (*fn)(unsigned long addr, unsigned int esr, struct pt_regs *regs);
- int sig;
- int code;
- const char *name;
-} fault_info[] = {
+static const struct fault_info fault_info[] = {
{ do_bad, SIGBUS, 0, "ttbr address size fault" },
{ do_bad, SIGBUS, 0, "level 1 address size fault" },
{ do_bad, SIGBUS, 0, "level 2 address size fault" },
@@ -507,10 +526,10 @@ static const struct fault_info {
{ 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)" },
- { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" },
- { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" },
- { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" },
+ { do_bad, SIGBUS, 0, "synchronous external abort (translation table walk)" },
+ { do_bad, SIGBUS, 0, "synchronous external abort (translation table walk)" },
+ { do_bad, SIGBUS, 0, "synchronous external abort (translation table walk)" },
+ { do_bad, SIGBUS, 0, "synchronous external abort (translation table walk)" },
{ do_bad, SIGBUS, 0, "synchronous parity error" },
{ do_bad, SIGBUS, 0, "unknown 25" },
{ do_bad, SIGBUS, 0, "unknown 26" },
@@ -553,19 +572,13 @@ static const struct fault_info {
{ do_bad, SIGBUS, 0, "unknown 63" },
};
-static const char *fault_name(unsigned int esr)
-{
- const struct fault_info *inf = fault_info + (esr & 63);
- return inf->name;
-}
-
/*
* Dispatch a data abort to the relevant handler.
*/
asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,
struct pt_regs *regs)
{
- const struct fault_info *inf = fault_info + (esr & 63);
+ const struct fault_info *inf = esr_to_fault_info(esr);
struct siginfo info;
if (!inf->fn(addr, esr, regs))
@@ -685,17 +698,3 @@ int cpu_enable_pan(void *__unused)
return 0;
}
#endif /* CONFIG_ARM64_PAN */
-
-#ifdef CONFIG_ARM64_UAO
-/*
- * Kernel threads have fs=KERNEL_DS by default, and don't need to call
- * set_fs(), devtmpfs in particular relies on this behaviour.
- * We need to enable the feature at runtime (instead of adding it to
- * PSR_MODE_EL1h) as the feature may not be implemented by the cpu.
- */
-int cpu_enable_uao(void *__unused)
-{
- asm(SET_PSTATE_UAO(1));
- return 0;
-}
-#endif /* CONFIG_ARM64_UAO */
generated by cgit v1.2.3 (git 2.46.0) at 2025-08-11 04:46:42 +0000