diff options
| -rw-r--r-- | arch/x86/kernel/sev.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/umip.c | 10 | ||||
| -rw-r--r-- | arch/x86/lib/insn-eval.c | 16 |
3 files changed, 16 insertions, 18 deletions
diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index 4fd997bbf059..a1eeaa79bf2b 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -258,17 +258,17 @@ static int vc_fetch_insn_kernel(struct es_em_ctxt *ctxt, static enum es_result __vc_decode_user_insn(struct es_em_ctxt *ctxt) { char buffer[MAX_INSN_SIZE]; - int res; + int insn_bytes; - res = insn_fetch_from_user_inatomic(ctxt->regs, buffer); - if (!res) { + insn_bytes = insn_fetch_from_user_inatomic(ctxt->regs, buffer); + if (insn_bytes <= 0) { ctxt->fi.vector = X86_TRAP_PF; ctxt->fi.error_code = X86_PF_INSTR | X86_PF_USER; ctxt->fi.cr2 = ctxt->regs->ip; return ES_EXCEPTION; } - if (!insn_decode_from_regs(&ctxt->insn, ctxt->regs, buffer, res)) + if (!insn_decode_from_regs(&ctxt->insn, ctxt->regs, buffer, insn_bytes)) return ES_DECODE_FAILED; if (ctxt->insn.immediate.got) diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c index 8daa70b0d2da..576b47e7523d 100644 --- a/arch/x86/kernel/umip.c +++ b/arch/x86/kernel/umip.c @@ -346,14 +346,12 @@ bool fixup_umip_exception(struct pt_regs *regs) if (!regs) return false; - nr_copied = insn_fetch_from_user(regs, buf); - /* - * The insn_fetch_from_user above could have failed if user code - * is protected by a memory protection key. Give up on emulation - * in such a case. Should we issue a page fault? + * Give up on emulation if fetching the instruction failed. Should a + * page fault or a #GP be issued? */ - if (!nr_copied) + nr_copied = insn_fetch_from_user(regs, buf); + if (nr_copied <= 0) return false; if (!insn_decode_from_regs(&insn, regs, buf, nr_copied)) diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index 4eecb9c7c6a0..a1d24fdc07cf 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -1448,9 +1448,9 @@ static int insn_get_effective_ip(struct pt_regs *regs, unsigned long *ip) * * Returns: * - * Number of instruction bytes copied. - * - * 0 if nothing was copied. + * - number of instruction bytes copied. + * - 0 if nothing was copied. + * - -EINVAL if the linear address of the instruction could not be calculated */ int insn_fetch_from_user(struct pt_regs *regs, unsigned char buf[MAX_INSN_SIZE]) { @@ -1458,7 +1458,7 @@ int insn_fetch_from_user(struct pt_regs *regs, unsigned char buf[MAX_INSN_SIZE]) int not_copied; if (insn_get_effective_ip(regs, &ip)) - return 0; + return -EINVAL; not_copied = copy_from_user(buf, (void __user *)ip, MAX_INSN_SIZE); @@ -1476,9 +1476,9 @@ int insn_fetch_from_user(struct pt_regs *regs, unsigned char buf[MAX_INSN_SIZE]) * * Returns: * - * Number of instruction bytes copied. - * - * 0 if nothing was copied. + * - number of instruction bytes copied. + * - 0 if nothing was copied. + * - -EINVAL if the linear address of the instruction could not be calculated. */ int insn_fetch_from_user_inatomic(struct pt_regs *regs, unsigned char buf[MAX_INSN_SIZE]) { @@ -1486,7 +1486,7 @@ int insn_fetch_from_user_inatomic(struct pt_regs *regs, unsigned char buf[MAX_IN int not_copied; if (insn_get_effective_ip(regs, &ip)) - return 0; + return -EINVAL; not_copied = __copy_from_user_inatomic(buf, (void __user *)ip, MAX_INSN_SIZE); |