diff options
| -rw-r--r-- | arch/riscv/kernel/traps.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 8895c8197519..141036d06015 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -34,7 +34,21 @@ int show_unhandled_signals = 1; static DEFINE_SPINLOCK(die_lock); -static void dump_kernel_instr(const char *loglvl, struct pt_regs *regs) +static int copy_code(struct pt_regs *regs, u16 *val, const u16 *insns) +{ + const void __user *uaddr = (__force const void __user *)insns; + + if (!user_mode(regs)) + return get_kernel_nofault(*val, insns); + + /* The user space code from other tasks cannot be accessed. */ + if (regs != task_pt_regs(current)) + return -EPERM; + + return copy_from_user_nofault(val, uaddr, sizeof(*val)); +} + +static void dump_instr(const char *loglvl, struct pt_regs *regs) { char str[sizeof("0000 ") * 12 + 2 + 1], *p = str; const u16 *insns = (u16 *)instruction_pointer(regs); @@ -43,7 +57,7 @@ static void dump_kernel_instr(const char *loglvl, struct pt_regs *regs) int i; for (i = -10; i < 2; i++) { - bad = get_kernel_nofault(val, &insns[i]); + bad = copy_code(regs, &val, &insns[i]); if (!bad) { p += sprintf(p, i == 0 ? "(%04hx) " : "%04hx ", val); } else { @@ -72,7 +86,7 @@ void die(struct pt_regs *regs, const char *str) print_modules(); if (regs) { show_regs(regs); - dump_kernel_instr(KERN_EMERG, regs); + dump_instr(KERN_EMERG, regs); } cause = regs ? regs->cause : -1; @@ -105,6 +119,7 @@ void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr) print_vma_addr(KERN_CONT " in ", instruction_pointer(regs)); pr_cont("\n"); __show_regs(regs); + dump_instr(KERN_EMERG, regs); } force_sig_fault(signo, code, (void __user *)addr); |