git@vger.kernel.org mailing list mirror (one of many)
 help / color / mirror / code / Atom feed
From: "İsmail Dönmez via GitGitGadget" <gitgitgadget@gmail.com>
To: git@vger.kernel.org
Cc: "Junio C Hamano" <gitster@pobox.com>, "İsmail Dönmez" <ismail@i10z.com>
Subject: [PATCH v2 1/2] mingw: do not let ld strip relocations
Date: Wed, 08 May 2019 04:30:58 -0700 (PDT)	[thread overview]
Message-ID: <828913e96c77ba4eb94b35cb4c1f1bf92b2e1c3f.1557315057.git.gitgitgadget@gmail.com> (raw)
In-Reply-To: <pull.134.v2.git.gitgitgadget@gmail.com>

From: =?UTF-8?q?=C4=B0smail=20D=C3=B6nmez?= <ismail@i10z.com>

This is the first step for enabling ASLR (Address Space Layout
Randomization) support. We want to enable ASLR for better protection
against exploiting security holes in Git: it makes it harder to attack
software by making code addresses unpredictable.

The problem fixed by this commit is that `ld.exe` seems to be stripping
relocations which in turn will break ASLR support. We just make sure
it's not stripping the main executable entry.

Signed-off-by: İsmail Dönmez <ismail@i10z.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.mak.uname | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/config.mak.uname b/config.mak.uname
index 3605fead53..f2ac755753 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -576,10 +576,12 @@ else
 		ifeq (MINGW32,$(MSYSTEM))
 			prefix = /mingw32
 			HOST_CPU = i686
+			BASIC_LDFLAGS += -Wl,--pic-executable,-e,_mainCRTStartup
 		endif
 		ifeq (MINGW64,$(MSYSTEM))
 			prefix = /mingw64
 			HOST_CPU = x86_64
+			BASIC_LDFLAGS += -Wl,--pic-executable,-e,mainCRTStartup
 		else
 			COMPAT_CFLAGS += -D_USE_32BIT_TIME_T
 			BASIC_LDFLAGS += -Wl,--large-address-aware
-- 
gitgitgadget


  reply	other threads:[~2019-05-08 11:31 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-29 21:56 [PATCH 0/2] Enable Data Execution Protection and Address Space Layout Randomization on Windows Johannes Schindelin via GitGitGadget
2019-04-29 21:56 ` [PATCH 1/2] mingw: do not let ld strip relocations İsmail Dönmez via GitGitGadget
2019-04-29 21:56 ` [PATCH 2/2] mingw: enable DEP and ASLR İsmail Dönmez via GitGitGadget
2019-04-30  6:26   ` Johannes Sixt
2019-04-30 22:41     ` Johannes Schindelin
2019-04-30 22:59       ` Johannes Sixt
2019-05-01 18:39       ` Alban Gruin
2019-05-01 23:36         ` brian m. carlson
2019-05-08 11:33           ` Johannes Schindelin
2019-05-08 11:33         ` Johannes Schindelin
2019-05-01 20:46       ` Jeff King
2019-05-01 22:02         ` Jonathan Nieder
2019-05-08 11:27           ` Johannes Schindelin
2019-05-08 11:30 ` [PATCH v2 0/2] Enable Data Execution Protection and Address Space Layout Randomization on Windows Johannes Schindelin via GitGitGadget
2019-05-08 11:30   ` İsmail Dönmez via GitGitGadget [this message]
2019-05-08 11:30   ` [PATCH v2 2/2] mingw: enable DEP and ASLR İsmail Dönmez via GitGitGadget

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: http://vger.kernel.org/majordomo-info.html

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=828913e96c77ba4eb94b35cb4c1f1bf92b2e1c3f.1557315057.git.gitgitgadget@gmail.com \
    --to=gitgitgadget@gmail.com \
    --cc=git@vger.kernel.org \
    --cc=gitster@pobox.com \
    --cc=ismail@i10z.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
Code repositories for project(s) associated with this public inbox

	https://80x24.org/mirrors/git.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).