diff options
Diffstat (limited to 'arch/x86/lib/insn-eval.c')
-rw-r--r-- | arch/x86/lib/insn-eval.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index 1c23ec0..91f08aa 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -729,25 +729,29 @@ int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs) } /** - * get_seg_base_addr() - obtain base address of a segment + * get_seg_base_limit() - obtain base address and limit of a segment * @insn: Instruction. Must be valid. * @regs: Register values as seen when entering kernel mode * @regoff: Operand offset, in pt_regs, used to resolve segment descriptor * @base: Obtained segment base + * @limit: Obtained segment limit * - * Obtain the base address of the segment associated with the operand @regoff - * and, if any or allowed, override prefixes in @insn. This function is + * Obtain the base address and limit of the segment associated with the operand + * @regoff and, if any or allowed, override prefixes in @insn. This function is * different from insn_get_seg_base() as the latter does not resolve the segment - * associated with the instruction operand. + * associated with the instruction operand. If a limit is not needed (e.g., + * when running in long mode), @limit can be NULL. * * Returns: * - * 0 on success. @base will contain the base address of the resolved segment. + * 0 on success. @base and @limit will contain the base address and of the + * resolved segment, respectively. * * -EINVAL on error. */ -static int get_seg_base_addr(struct insn *insn, struct pt_regs *regs, - int regoff, unsigned long *base) +static int get_seg_base_limit(struct insn *insn, struct pt_regs *regs, + int regoff, unsigned long *base, + unsigned long *limit) { int seg_reg_idx; @@ -762,6 +766,13 @@ static int get_seg_base_addr(struct insn *insn, struct pt_regs *regs, if (*base == -1L) return -EINVAL; + if (!limit) + return 0; + + *limit = get_seg_limit(regs, seg_reg_idx); + if (!(*limit)) + return -EINVAL; + return 0; } @@ -843,7 +854,7 @@ void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs) eff_addr += insn->displacement.value; } - ret = get_seg_base_addr(insn, regs, addr_offset, &seg_base); + ret = get_seg_base_limit(insn, regs, addr_offset, &seg_base, NULL); if (ret) goto out; |