![Ingo Molnar](/assets/img/avatar_default.png)
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/debug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
695 lines
19 KiB
C
695 lines
19 KiB
C
/*
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* Based on arch/arm/mm/fault.c
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*
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* Copyright (C) 1995 Linus Torvalds
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* Copyright (C) 1995-2004 Russell King
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* Copyright (C) 2012 ARM Ltd.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <linux/extable.h>
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#include <linux/signal.h>
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#include <linux/mm.h>
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#include <linux/hardirq.h>
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#include <linux/init.h>
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#include <linux/kprobes.h>
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#include <linux/uaccess.h>
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#include <linux/page-flags.h>
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#include <linux/sched/signal.h>
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#include <linux/sched/debug.h>
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#include <linux/highmem.h>
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#include <linux/perf_event.h>
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#include <linux/preempt.h>
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#include <asm/bug.h>
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#include <asm/cpufeature.h>
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#include <asm/exception.h>
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#include <asm/debug-monitors.h>
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#include <asm/esr.h>
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#include <asm/sysreg.h>
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#include <asm/system_misc.h>
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#include <asm/pgtable.h>
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#include <asm/tlbflush.h>
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static const char *fault_name(unsigned int esr);
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#ifdef CONFIG_KPROBES
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static inline int notify_page_fault(struct pt_regs *regs, unsigned int esr)
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{
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int ret = 0;
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/* kprobe_running() needs smp_processor_id() */
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if (!user_mode(regs)) {
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preempt_disable();
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if (kprobe_running() && kprobe_fault_handler(regs, esr))
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ret = 1;
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preempt_enable();
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}
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return ret;
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}
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#else
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static inline int notify_page_fault(struct pt_regs *regs, unsigned int esr)
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{
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return 0;
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}
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#endif
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/*
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* Dump out the page tables associated with 'addr' in mm 'mm'.
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*/
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void show_pte(struct mm_struct *mm, unsigned long addr)
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{
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pgd_t *pgd;
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if (!mm)
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mm = &init_mm;
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pr_alert("pgd = %p\n", mm->pgd);
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pgd = pgd_offset(mm, addr);
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pr_alert("[%08lx] *pgd=%016llx", addr, pgd_val(*pgd));
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do {
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pud_t *pud;
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pmd_t *pmd;
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pte_t *pte;
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if (pgd_none(*pgd) || pgd_bad(*pgd))
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break;
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pud = pud_offset(pgd, addr);
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pr_cont(", *pud=%016llx", pud_val(*pud));
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if (pud_none(*pud) || pud_bad(*pud))
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break;
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pmd = pmd_offset(pud, addr);
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pr_cont(", *pmd=%016llx", pmd_val(*pmd));
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if (pmd_none(*pmd) || pmd_bad(*pmd))
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break;
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pte = pte_offset_map(pmd, addr);
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pr_cont(", *pte=%016llx", pte_val(*pte));
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pte_unmap(pte);
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} while(0);
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pr_cont("\n");
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}
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#ifdef CONFIG_ARM64_HW_AFDBM
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/*
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* This function sets the access flags (dirty, accessed), as well as write
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* permission, and only to a more permissive setting.
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*
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* It needs to cope with hardware update of the accessed/dirty state by other
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* agents in the system and can safely skip the __sync_icache_dcache() call as,
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* like set_pte_at(), the PTE is never changed from no-exec to exec here.
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*
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* Returns whether or not the PTE actually changed.
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*/
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int ptep_set_access_flags(struct vm_area_struct *vma,
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unsigned long address, pte_t *ptep,
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pte_t entry, int dirty)
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{
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pteval_t old_pteval;
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unsigned int tmp;
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if (pte_same(*ptep, entry))
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return 0;
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/* only preserve the access flags and write permission */
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pte_val(entry) &= PTE_AF | PTE_WRITE | PTE_DIRTY;
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/*
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* PTE_RDONLY is cleared by default in the asm below, so set it in
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* back if necessary (read-only or clean PTE).
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*/
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if (!pte_write(entry) || !pte_sw_dirty(entry))
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pte_val(entry) |= PTE_RDONLY;
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/*
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* Setting the flags must be done atomically to avoid racing with the
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* hardware update of the access/dirty state.
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*/
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asm volatile("// ptep_set_access_flags\n"
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" prfm pstl1strm, %2\n"
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"1: ldxr %0, %2\n"
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" and %0, %0, %3 // clear PTE_RDONLY\n"
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" orr %0, %0, %4 // set flags\n"
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" stxr %w1, %0, %2\n"
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" cbnz %w1, 1b\n"
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: "=&r" (old_pteval), "=&r" (tmp), "+Q" (pte_val(*ptep))
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: "L" (~PTE_RDONLY), "r" (pte_val(entry)));
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flush_tlb_fix_spurious_fault(vma, address);
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return 1;
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}
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#endif
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static bool is_el1_instruction_abort(unsigned int esr)
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{
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return ESR_ELx_EC(esr) == ESR_ELx_EC_IABT_CUR;
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}
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/*
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* The kernel tried to access some page that wasn't present.
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*/
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static void __do_kernel_fault(struct mm_struct *mm, unsigned long addr,
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unsigned int esr, struct pt_regs *regs)
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{
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/*
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* Are we prepared to handle this kernel fault?
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* We are almost certainly not prepared to handle instruction faults.
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*/
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if (!is_el1_instruction_abort(esr) && fixup_exception(regs))
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return;
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/*
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* No handler, we'll have to terminate things with extreme prejudice.
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*/
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bust_spinlocks(1);
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pr_alert("Unable to handle kernel %s at virtual address %08lx\n",
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(addr < PAGE_SIZE) ? "NULL pointer dereference" :
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"paging request", addr);
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show_pte(mm, addr);
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die("Oops", regs, esr);
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bust_spinlocks(0);
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do_exit(SIGKILL);
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}
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/*
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* Something tried to access memory that isn't in our memory map. User mode
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* accesses just cause a SIGSEGV
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*/
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static void __do_user_fault(struct task_struct *tsk, unsigned long addr,
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unsigned int esr, unsigned int sig, int code,
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struct pt_regs *regs)
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{
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struct siginfo si;
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if (unhandled_signal(tsk, sig) && show_unhandled_signals_ratelimited()) {
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pr_info("%s[%d]: unhandled %s (%d) at 0x%08lx, esr 0x%03x\n",
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tsk->comm, task_pid_nr(tsk), fault_name(esr), sig,
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addr, esr);
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show_pte(tsk->mm, addr);
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show_regs(regs);
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}
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tsk->thread.fault_address = addr;
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tsk->thread.fault_code = esr;
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si.si_signo = sig;
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si.si_errno = 0;
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si.si_code = code;
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si.si_addr = (void __user *)addr;
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force_sig_info(sig, &si, tsk);
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}
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static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *regs)
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{
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struct task_struct *tsk = current;
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struct mm_struct *mm = tsk->active_mm;
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/*
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* If we are in kernel mode at this point, we have no context to
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* handle this fault with.
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*/
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if (user_mode(regs))
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__do_user_fault(tsk, addr, esr, SIGSEGV, SEGV_MAPERR, regs);
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else
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__do_kernel_fault(mm, addr, esr, regs);
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}
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#define VM_FAULT_BADMAP 0x010000
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#define VM_FAULT_BADACCESS 0x020000
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static int __do_page_fault(struct mm_struct *mm, unsigned long addr,
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unsigned int mm_flags, unsigned long vm_flags,
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struct task_struct *tsk)
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{
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struct vm_area_struct *vma;
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int fault;
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vma = find_vma(mm, addr);
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fault = VM_FAULT_BADMAP;
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if (unlikely(!vma))
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goto out;
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if (unlikely(vma->vm_start > addr))
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goto check_stack;
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/*
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* Ok, we have a good vm_area for this memory access, so we can handle
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* it.
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*/
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good_area:
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/*
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* Check that the permissions on the VMA allow for the fault which
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* occurred.
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*/
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if (!(vma->vm_flags & vm_flags)) {
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fault = VM_FAULT_BADACCESS;
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goto out;
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}
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return handle_mm_fault(vma, addr & PAGE_MASK, mm_flags);
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check_stack:
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if (vma->vm_flags & VM_GROWSDOWN && !expand_stack(vma, addr))
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goto good_area;
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out:
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return fault;
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}
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static inline bool is_permission_fault(unsigned int esr, struct pt_regs *regs)
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{
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unsigned int ec = ESR_ELx_EC(esr);
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unsigned int fsc_type = esr & ESR_ELx_FSC_TYPE;
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if (ec != ESR_ELx_EC_DABT_CUR && ec != ESR_ELx_EC_IABT_CUR)
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return false;
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if (system_uses_ttbr0_pan())
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return fsc_type == ESR_ELx_FSC_FAULT &&
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(regs->pstate & PSR_PAN_BIT);
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else
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return fsc_type == ESR_ELx_FSC_PERM;
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}
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static bool is_el0_instruction_abort(unsigned int esr)
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{
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return ESR_ELx_EC(esr) == ESR_ELx_EC_IABT_LOW;
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}
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static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
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struct pt_regs *regs)
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{
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struct task_struct *tsk;
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struct mm_struct *mm;
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int fault, sig, code;
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unsigned long vm_flags = VM_READ | VM_WRITE;
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unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
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if (notify_page_fault(regs, esr))
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return 0;
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tsk = current;
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mm = tsk->mm;
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/*
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* If we're in an interrupt or have no user context, we must not take
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* the fault.
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*/
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if (faulthandler_disabled() || !mm)
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goto no_context;
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if (user_mode(regs))
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mm_flags |= FAULT_FLAG_USER;
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if (is_el0_instruction_abort(esr)) {
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vm_flags = VM_EXEC;
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} else if ((esr & ESR_ELx_WNR) && !(esr & ESR_ELx_CM)) {
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vm_flags = VM_WRITE;
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mm_flags |= FAULT_FLAG_WRITE;
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}
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if (addr < USER_DS && is_permission_fault(esr, regs)) {
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/* regs->orig_addr_limit may be 0 if we entered from EL0 */
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if (regs->orig_addr_limit == KERNEL_DS)
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die("Accessing user space memory with fs=KERNEL_DS", regs, esr);
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if (is_el1_instruction_abort(esr))
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die("Attempting to execute userspace memory", regs, esr);
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if (!search_exception_tables(regs->pc))
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die("Accessing user space memory outside uaccess.h routines", regs, esr);
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}
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/*
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* As per x86, we may deadlock here. However, since the kernel only
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* validly references user space from well defined areas of the code,
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* we can bug out early if this is from code which shouldn't.
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*/
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if (!down_read_trylock(&mm->mmap_sem)) {
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if (!user_mode(regs) && !search_exception_tables(regs->pc))
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goto no_context;
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retry:
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down_read(&mm->mmap_sem);
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} else {
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/*
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* The above down_read_trylock() might have succeeded in which
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* case, we'll have missed the might_sleep() from down_read().
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*/
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might_sleep();
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#ifdef CONFIG_DEBUG_VM
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if (!user_mode(regs) && !search_exception_tables(regs->pc))
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goto no_context;
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#endif
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}
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fault = __do_page_fault(mm, addr, mm_flags, vm_flags, tsk);
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/*
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* If we need to retry but a fatal signal is pending, handle the
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* signal first. We do not need to release the mmap_sem because it
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* would already be released in __lock_page_or_retry in mm/filemap.c.
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*/
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if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
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return 0;
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/*
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* Major/minor page fault accounting is only done on the initial
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* attempt. If we go through a retry, it is extremely likely that the
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* page will be found in page cache at that point.
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*/
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perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr);
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if (mm_flags & FAULT_FLAG_ALLOW_RETRY) {
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if (fault & VM_FAULT_MAJOR) {
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tsk->maj_flt++;
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perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, regs,
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addr);
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} else {
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tsk->min_flt++;
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perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, regs,
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addr);
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}
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if (fault & VM_FAULT_RETRY) {
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/*
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* Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk of
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* starvation.
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*/
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mm_flags &= ~FAULT_FLAG_ALLOW_RETRY;
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mm_flags |= FAULT_FLAG_TRIED;
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goto retry;
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}
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}
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up_read(&mm->mmap_sem);
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/*
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* Handle the "normal" case first - VM_FAULT_MAJOR
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*/
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if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP |
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VM_FAULT_BADACCESS))))
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return 0;
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/*
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* If we are in kernel mode at this point, we have no context to
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* handle this fault with.
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*/
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if (!user_mode(regs))
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goto no_context;
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if (fault & VM_FAULT_OOM) {
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/*
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* We ran out of memory, call the OOM killer, and return to
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* userspace (which will retry the fault, or kill us if we got
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* oom-killed).
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*/
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pagefault_out_of_memory();
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return 0;
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}
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if (fault & VM_FAULT_SIGBUS) {
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/*
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* We had some memory, but were unable to successfully fix up
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* this page fault.
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*/
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sig = SIGBUS;
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code = BUS_ADRERR;
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} else {
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/*
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* Something tried to access memory that isn't in our memory
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* map.
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*/
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sig = SIGSEGV;
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code = fault == VM_FAULT_BADACCESS ?
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SEGV_ACCERR : SEGV_MAPERR;
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}
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__do_user_fault(tsk, addr, esr, sig, code, regs);
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return 0;
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no_context:
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__do_kernel_fault(mm, addr, esr, regs);
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return 0;
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}
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/*
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* First Level Translation Fault Handler
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*
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* We enter here because the first level page table doesn't contain a valid
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* entry for the address.
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*
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* If the address is in kernel space (>= TASK_SIZE), then we are probably
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* faulting in the vmalloc() area.
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*
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* If the init_task's first level page tables contains the relevant entry, we
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* copy the it to this task. If not, we send the process a signal, fixup the
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* exception, or oops the kernel.
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*
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* NOTE! We MUST NOT take any locks for this case. We may be in an interrupt
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* or a critical region, and should only copy the information from the master
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* page table, nothing more.
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*/
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static int __kprobes do_translation_fault(unsigned long addr,
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unsigned int esr,
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struct pt_regs *regs)
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{
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if (addr < TASK_SIZE)
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return do_page_fault(addr, esr, regs);
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do_bad_area(addr, esr, regs);
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return 0;
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}
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static int do_alignment_fault(unsigned long addr, unsigned int esr,
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struct pt_regs *regs)
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{
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do_bad_area(addr, esr, regs);
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return 0;
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}
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/*
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* This abort handler always returns "fault".
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*/
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static int do_bad(unsigned long addr, unsigned int esr, struct pt_regs *regs)
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{
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return 1;
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}
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static const struct fault_info {
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int (*fn)(unsigned long addr, unsigned int esr, struct pt_regs *regs);
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int sig;
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int code;
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const char *name;
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} fault_info[] = {
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{ do_bad, SIGBUS, 0, "ttbr address size fault" },
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{ do_bad, SIGBUS, 0, "level 1 address size fault" },
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{ do_bad, SIGBUS, 0, "level 2 address size fault" },
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{ do_bad, SIGBUS, 0, "level 3 address size fault" },
|
|
{ do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 0 translation fault" },
|
|
{ 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, "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, "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, "unknown 17" },
|
|
{ do_bad, SIGBUS, 0, "unknown 18" },
|
|
{ do_bad, SIGBUS, 0, "unknown 19" },
|
|
{ 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" },
|
|
{ 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, "unknown 32" },
|
|
{ do_alignment_fault, SIGBUS, BUS_ADRALN, "alignment fault" },
|
|
{ do_bad, SIGBUS, 0, "unknown 34" },
|
|
{ do_bad, SIGBUS, 0, "unknown 35" },
|
|
{ do_bad, SIGBUS, 0, "unknown 36" },
|
|
{ do_bad, SIGBUS, 0, "unknown 37" },
|
|
{ do_bad, SIGBUS, 0, "unknown 38" },
|
|
{ do_bad, SIGBUS, 0, "unknown 39" },
|
|
{ do_bad, SIGBUS, 0, "unknown 40" },
|
|
{ do_bad, SIGBUS, 0, "unknown 41" },
|
|
{ do_bad, SIGBUS, 0, "unknown 42" },
|
|
{ do_bad, SIGBUS, 0, "unknown 43" },
|
|
{ do_bad, SIGBUS, 0, "unknown 44" },
|
|
{ do_bad, SIGBUS, 0, "unknown 45" },
|
|
{ do_bad, SIGBUS, 0, "unknown 46" },
|
|
{ do_bad, SIGBUS, 0, "unknown 47" },
|
|
{ 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, "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, "unknown 58" },
|
|
{ do_bad, SIGBUS, 0, "unknown 59" },
|
|
{ do_bad, SIGBUS, 0, "unknown 60" },
|
|
{ do_bad, SIGBUS, 0, "section domain fault" },
|
|
{ do_bad, SIGBUS, 0, "page domain fault" },
|
|
{ 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);
|
|
struct siginfo info;
|
|
|
|
if (!inf->fn(addr, esr, regs))
|
|
return;
|
|
|
|
pr_alert("Unhandled fault: %s (0x%08x) at 0x%016lx\n",
|
|
inf->name, esr, addr);
|
|
|
|
info.si_signo = inf->sig;
|
|
info.si_errno = 0;
|
|
info.si_code = inf->code;
|
|
info.si_addr = (void __user *)addr;
|
|
arm64_notify_die("", regs, &info, esr);
|
|
}
|
|
|
|
/*
|
|
* Handle stack alignment exceptions.
|
|
*/
|
|
asmlinkage void __exception do_sp_pc_abort(unsigned long addr,
|
|
unsigned int esr,
|
|
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("Oops - SP/PC alignment exception", regs, &info, esr);
|
|
}
|
|
|
|
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" },
|
|
{ early_brk64, SIGTRAP, TRAP_BRKPT, "aarch64 BRK" },
|
|
{ do_bad, SIGBUS, 0, "unknown 7" },
|
|
};
|
|
|
|
void __init hook_debug_fault_code(int nr,
|
|
int (*fn)(unsigned long, unsigned int, struct pt_regs *),
|
|
int sig, int code, const char *name)
|
|
{
|
|
BUG_ON(nr < 0 || nr >= ARRAY_SIZE(debug_fault_info));
|
|
|
|
debug_fault_info[nr].fn = fn;
|
|
debug_fault_info[nr].sig = sig;
|
|
debug_fault_info[nr].code = code;
|
|
debug_fault_info[nr].name = name;
|
|
}
|
|
|
|
asmlinkage int __exception do_debug_exception(unsigned long addr,
|
|
unsigned int esr,
|
|
struct pt_regs *regs)
|
|
{
|
|
const struct fault_info *inf = debug_fault_info + DBG_ESR_EVT(esr);
|
|
struct siginfo info;
|
|
int rv;
|
|
|
|
/*
|
|
* Tell lockdep we disabled irqs in entry.S. Do nothing if they were
|
|
* already disabled to preserve the last enabled/disabled addresses.
|
|
*/
|
|
if (interrupts_enabled(regs))
|
|
trace_hardirqs_off();
|
|
|
|
if (!inf->fn(addr, esr, regs)) {
|
|
rv = 1;
|
|
} else {
|
|
pr_alert("Unhandled debug exception: %s (0x%08x) at 0x%016lx\n",
|
|
inf->name, esr, addr);
|
|
|
|
info.si_signo = inf->sig;
|
|
info.si_errno = 0;
|
|
info.si_code = inf->code;
|
|
info.si_addr = (void __user *)addr;
|
|
arm64_notify_die("", regs, &info, 0);
|
|
rv = 0;
|
|
}
|
|
|
|
if (interrupts_enabled(regs))
|
|
trace_hardirqs_on();
|
|
|
|
return rv;
|
|
}
|
|
NOKPROBE_SYMBOL(do_debug_exception);
|
|
|
|
#ifdef CONFIG_ARM64_PAN
|
|
int cpu_enable_pan(void *__unused)
|
|
{
|
|
/*
|
|
* We modify PSTATE. This won't work from irq context as the PSTATE
|
|
* is discarded once we return from the exception.
|
|
*/
|
|
WARN_ON_ONCE(in_interrupt());
|
|
|
|
config_sctlr_el1(SCTLR_EL1_SPAN, 0);
|
|
asm(SET_PSTATE_PAN(1));
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_ARM64_PAN */
|