renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2025-01-22 04:24:02 +08:00
Code

x86/insn: Add insn_has_rep_prefix() helper

Browse Source 
Add a function to check whether an instruction has a REP prefix.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lkml.kernel.org/r/20200907131613.12703-12-joro@8bytes.org
This commit is contained in:
Joerg Roedel 2020-09-07 15:15:12 +02:00 committed by Borislav Petkov
parent 7af1bd822d
commit 5901781a11
2 changed files with 25 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
arch/x86/include/asm/insn-eval.h
View File

@ -15,6 +15,7 @@
#define INSN_CODE_SEG_OPND_SZ(params) (params & 0xf)
#define INSN_CODE_SEG_PARAMS(oper_sz, addr_sz) (oper_sz | (addr_sz << 4))
bool insn_has_rep_prefix(struct insn *insn);
void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs);
int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs);
int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs);

24
arch/x86/lib/insn-eval.c
View File

@ -53,6 +53,30 @@ static bool is_string_insn(struct insn *insn)
}
}
/**
* insn_has_rep_prefix() - Determine if instruction has a REP prefix
* @insn: Instruction containing the prefix to inspect
*
* Returns:
*
* true if the instruction has a REP prefix, false if not.
*/
bool insn_has_rep_prefix(struct insn *insn)
{
int i;
insn_get_prefixes(insn);
for (i = 0; i < insn->prefixes.nbytes; i++) {
insn_byte_t p = insn->prefixes.bytes[i];
if (p == 0xf2 || p == 0xf3)
return true;
}
return false;
}
/**
* get_seg_reg_override_idx() - obtain segment register override index
* @insn: Valid instruction with segment override prefixes