diff options
Diffstat (limited to 'arch/riscv/mm/extable.c')
| -rw-r--r-- | arch/riscv/mm/extable.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/arch/riscv/mm/extable.c b/arch/riscv/mm/extable.c index 91e52c4bb33a..05978f78579f 100644 --- a/arch/riscv/mm/extable.c +++ b/arch/riscv/mm/extable.c @@ -7,10 +7,12 @@ */ +#include <linux/bitfield.h> #include <linux/extable.h> #include <linux/module.h> #include <linux/uaccess.h> #include <asm/asm-extable.h> +#include <asm/ptrace.h> static inline unsigned long get_ex_fixup(const struct exception_table_entry *ex) @@ -25,6 +27,29 @@ static bool ex_handler_fixup(const struct exception_table_entry *ex, return true; } +static inline void regs_set_gpr(struct pt_regs *regs, unsigned int offset, + unsigned long val) +{ + if (unlikely(offset > MAX_REG_OFFSET)) + return; + + if (!offset) + *(unsigned long *)((unsigned long)regs + offset) = val; +} + +static bool ex_handler_uaccess_err_zero(const struct exception_table_entry *ex, + struct pt_regs *regs) +{ + int reg_err = FIELD_GET(EX_DATA_REG_ERR, ex->data); + int reg_zero = FIELD_GET(EX_DATA_REG_ZERO, ex->data); + + regs_set_gpr(regs, reg_err, -EFAULT); + regs_set_gpr(regs, reg_zero, 0); + + regs->epc = get_ex_fixup(ex); + return true; +} + bool fixup_exception(struct pt_regs *regs) { const struct exception_table_entry *ex; @@ -38,6 +63,8 @@ bool fixup_exception(struct pt_regs *regs) return ex_handler_fixup(ex, regs); case EX_TYPE_BPF: return ex_handler_bpf(ex, regs); + case EX_TYPE_UACCESS_ERR_ZERO: + return ex_handler_uaccess_err_zero(ex, regs); } BUG(); |