linux-kernel - [PATCH 1/2] arch/x86/tools/objdump_reformat.awk: Ensure regex matches fwait

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220106023606.283953-2-samuelzeter@gmail.com>
Date:   Thu,  6 Jan 2022 13:36:04 +1100
From:   Samuel Zeter <samuelzeter@...il.com>
To:     unlisted-recipients:; (no To-header on input)
Cc:     samuelzeter@...il.com, Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org,
        "H. Peter Anvin" <hpa@...or.com>,
        Nathan Chancellor <nathan@...nel.org>,
        Nick Desaulniers <ndesaulniers@...gle.com>,
        linux-kernel@...r.kernel.org, llvm@...ts.linux.dev
Subject: [PATCH 1/2] arch/x86/tools/objdump_reformat.awk: Ensure regex matches fwait

If there is "wait" mnemonic in the line being parsed, it is incorrectly
handled by the script, and an extra line of "fwait" in
objdump_reformat's output is inserted. As insn_decoder_test relies
upon the formatted output, the test fails.

This is reproducible when disassembling with llvm-objdump:

Pre-processed lines:
ffffffff81033e72: 9b                    wait
ffffffff81033e73: 48 c7 c7 89 50 42 82  movq

After objdump_reformat.awk:
ffffffff81033e72:       9b      fwait
ffffffff81033e72:                               wait
ffffffff81033e73:       48 c7 c7 89 50 42 82    movq

This patch fixes the issue by requiring spaces, or tabs, along with the
"fwait" instruction in the regex match.

Signed-off-by: Samuel Zeter <samuelzeter@...il.com>
---
 arch/x86/tools/objdump_reformat.awk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/tools/objdump_reformat.awk b/arch/x86/tools/objdump_reformat.awk
index f418c91b71f0..276e572a6f60 100644
--- a/arch/x86/tools/objdump_reformat.awk
+++ b/arch/x86/tools/objdump_reformat.awk
@@ -12,7 +12,7 @@ BEGIN {
 	prev_hex = ""
 	prev_mnemonic = ""
 	bad_expr = "(\\(bad\\)|^rex|^.byte|^rep(z|nz)$|^lock$|^es$|^cs$|^ss$|^ds$|^fs$|^gs$|^data(16|32)$|^addr(16|32|64))"
-	fwait_expr = "^9b "
+	fwait_expr = "^9b[ \t]*fwait"
 	fwait_str="9b\tfwait"
 }
 
-- 
2.32.0