50 lines
1.4 KiB
C
50 lines
1.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* linux/arch/frv/mm/extable.c
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*/
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#include <linux/extable.h>
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#include <linux/spinlock.h>
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#include <linux/uaccess.h>
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extern const void __memset_end, __memset_user_error_lr, __memset_user_error_handler;
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extern const void __memcpy_end, __memcpy_user_error_lr, __memcpy_user_error_handler;
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extern spinlock_t modlist_lock;
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int fixup_exception(struct pt_regs *regs)
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{
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const struct exception_table_entry *extab;
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unsigned long pc = regs->pc;
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/* determine if the fault lay during a memcpy_user or a memset_user */
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if (regs->lr == (unsigned long) &__memset_user_error_lr &&
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(unsigned long) &memset <= pc && pc < (unsigned long) &__memset_end
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) {
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/* the fault occurred in a protected memset
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* - we search for the return address (in LR) instead of the program counter
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* - it was probably during a clear_user()
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*/
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regs->pc = (unsigned long) &__memset_user_error_handler;
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return 1;
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}
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if (regs->lr == (unsigned long) &__memcpy_user_error_lr &&
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(unsigned long) &memcpy <= pc && pc < (unsigned long) &__memcpy_end
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) {
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/* the fault occurred in a protected memset
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* - we search for the return address (in LR) instead of the program counter
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* - it was probably during a copy_to/from_user()
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*/
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regs->pc = (unsigned long) &__memcpy_user_error_handler;
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return 1;
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}
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extab = search_exception_tables(pc);
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if (extab) {
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regs->pc = extab->fixup;
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return 1;
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}
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return 0;
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}
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