We are not in a critical failure path. The invalid register type is caused when trying to decode invalid instruction bytes from a user-space program. Thus, simply print an error message. To prevent this warning from being abused from user space programs, use the rate-limited variant of pr_err(). along with a descriptive prefix.
Cc: Borislav Petkov <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Adam Buchbinder <[email protected]> Cc: Colin Ian King <[email protected]> Cc: Lorenzo Stoakes <[email protected]> Cc: Qiaowei Ren <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Kees Cook <[email protected]> Cc: Thomas Garnier <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Ravi V. Shankar <[email protected]> Cc: [email protected] Signed-off-by: Ricardo Neri <[email protected]> --- arch/x86/lib/insn-eval.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index df9418c..4931d92 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -5,10 +5,14 @@ */ #include <linux/kernel.h> #include <linux/string.h> +#include <linux/ratelimit.h> #include <asm/inat.h> #include <asm/insn.h> #include <asm/insn-eval.h> +#undef pr_fmt +#define pr_fmt(fmt) "insn: " fmt + enum reg_type { REG_TYPE_RM = 0, REG_TYPE_INDEX, @@ -85,9 +89,8 @@ static int get_reg_offset(struct insn *insn, struct pt_regs *regs, break; default: - pr_err("invalid register type"); - BUG(); - break; + pr_err_ratelimited("invalid register type: %d\n", type); + return -EINVAL; } if (regno >= nr_registers) { -- 2.7.4
