LKML Archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: Greg Ungerer <gerg@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>,
	linux-arm-kernel@lists.infradead.org,
	linux-c6x-dev@linux-c6x.org,
	uclinux-h8-devel@lists.sourceforge.jp,
	linux-m68k@lists.linux-m68k.org, linux-riscv@lists.infradead.org,
	linux-sh@vger.kernel.org, linux-xtensa@linux-xtensa.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH 14/15] binfmt_flat: don't offset the data start
Date: Mon, 10 Jun 2019 23:20:14 +0200	[thread overview]
Message-ID: <20190610212015.9157-15-hch@lst.de> (raw)
In-Reply-To: <20190610212015.9157-1-hch@lst.de>

Ever since the initial commit of the binfmt_flat shared library
support back in the bitkeeper days we've offset the actual in-memory
.data start by one field per possible shared library, or 1 in case
shared library support isn't enabled.  I can't find anything in the
loader that actually makes use of it, nor was it present before
shared library support it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/binfmt_flat.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 2c7f32d5435f..e1ccc9f14150 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -572,7 +572,7 @@ static int load_flat_file(struct linux_binprm *bprm,
 			goto err;
 		}
 
-		len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
+		len = data_len + extra;
 		len = PAGE_ALIGN(len);
 		realdatastart = vm_mmap(NULL, 0, len,
 			PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
@@ -586,9 +586,7 @@ static int load_flat_file(struct linux_binprm *bprm,
 			vm_munmap(textpos, text_len);
 			goto err;
 		}
-		datapos = ALIGN(realdatastart +
-				MAX_SHARED_LIBS * sizeof(unsigned long),
-				FLAT_DATA_ALIGN);
+		datapos = ALIGN(realdatastart, FLAT_DATA_ALIGN);
 
 		pr_debug("Allocated data+bss+stack (%u bytes): %lx\n",
 			 data_len + bss_len + stack_len, datapos);
@@ -618,7 +616,7 @@ static int load_flat_file(struct linux_binprm *bprm,
 		memp_size = len;
 	} else {
 
-		len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(u32);
+		len = text_len + data_len + extra;
 		len = PAGE_ALIGN(len);
 		textpos = vm_mmap(NULL, 0, len,
 			PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
@@ -633,9 +631,7 @@ static int load_flat_file(struct linux_binprm *bprm,
 		}
 
 		realdatastart = textpos + ntohl(hdr->data_start);
-		datapos = ALIGN(realdatastart +
-				MAX_SHARED_LIBS * sizeof(u32),
-				FLAT_DATA_ALIGN);
+		datapos = ALIGN(realdatastart, FLAT_DATA_ALIGN);
 
 		reloc = (__be32 __user *)
 			(datapos + (ntohl(hdr->reloc_start) - text_len));
@@ -652,8 +648,9 @@ static int load_flat_file(struct linux_binprm *bprm,
 					 (text_len + full_data
 						  - sizeof(struct flat_hdr)),
 					 0);
-			memmove((void *) datapos, (void *) realdatastart,
-					full_data);
+			if (datapos != realdatastart)
+				memmove((void *)datapos, (void *)realdatastart,
+						full_data);
 #else
 			/*
 			 * This is used on MMU systems mainly for testing.
@@ -709,8 +706,7 @@ static int load_flat_file(struct linux_binprm *bprm,
 		if (IS_ERR_VALUE(result)) {
 			ret = result;
 			pr_err("Unable to read code+data+bss, errno %d\n", ret);
-			vm_munmap(textpos, text_len + data_len + extra +
-				MAX_SHARED_LIBS * sizeof(u32));
+			vm_munmap(textpos, text_len + data_len + extra);
 			goto err;
 		}
 	}
-- 
2.20.1


  parent reply	other threads:[~2019-06-10 21:21 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-10 21:20 binfmt_flat cleanups and RISC-V support Christoph Hellwig
2019-06-10 21:20 ` [PATCH 01/15] binfmt_flat: remove flat_reloc_valid Christoph Hellwig
2019-06-11  9:44   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 02/15] binfmt_flat: remove flat_set_persistent Christoph Hellwig
2019-06-11  9:45   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 03/15] binfmt_flat: provide a default version of flat_get_relocate_addr Christoph Hellwig
2019-06-11  9:46   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 04/15] binfmt_flat: remove flat_old_ram_flag Christoph Hellwig
2019-06-11  6:04   ` Greg Ungerer
2019-06-11  7:36     ` Christoph Hellwig
2019-06-11 13:07       ` Greg Ungerer
2019-06-11  9:47   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 05/15] binfmt_flat: replace flat_argvp_envp_on_stack with a Kconfig variable Christoph Hellwig
2019-06-11  9:49   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 06/15] binfmt_flat: remove the uapi <linux/flat.h> header Christoph Hellwig
2019-06-11  9:51   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 07/15] binfmt_flat: use __be32 for the on-disk format Christoph Hellwig
2019-06-11  8:25   ` Geert Uytterhoeven
2019-06-11  9:57   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 08/15] binfmt_flat: add endianess annotations Christoph Hellwig
2019-06-11  9:58   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 09/15] binfmt_flat: add a ARCH_HAS_BINFMT_FLAT option Christoph Hellwig
2019-06-11  9:59   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 10/15] binfmt_flat: make support for old format binaries optional Christoph Hellwig
2019-06-10 21:20 ` [PATCH 11/15] binfmt_flat: provide an asm-generic/flat.h Christoph Hellwig
2019-06-11 10:01   ` Vladimir Murzin
2019-06-10 21:20 ` [PATCH 12/15] binfmt_flat: remove the persistent argument from flat_get_addr_from_rp Christoph Hellwig
2019-06-10 21:20 ` [PATCH 13/15] binfmt_flat: move the MAX_SHARED_LIBS definition to binfmt_flat.c Christoph Hellwig
2019-06-10 21:20 ` Christoph Hellwig [this message]
2019-06-10 21:20 ` [PATCH 15/15] riscv: add binfmt_flat support Christoph Hellwig
2019-06-11  8:16   ` Vladimir Murzin
2019-06-11  9:20     ` Christoph Hellwig
2019-06-11  6:51 ` binfmt_flat cleanups and RISC-V support Greg Ungerer
2019-06-11  7:38   ` Christoph Hellwig
2019-06-11 13:02     ` Greg Ungerer
2019-06-11  8:05 ` Vladimir Murzin
2019-06-11  8:11   ` Christoph Hellwig
2019-06-11 10:08     ` Vladimir Murzin

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

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

  git send-email \
    --in-reply-to=20190610212015.9157-15-hch@lst.de \
    --to=hch@lst.de \
    --cc=gerg@linux-m68k.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-c6x-dev@linux-c6x.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-m68k@lists.linux-m68k.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=linux-sh@vger.kernel.org \
    --cc=linux-xtensa@linux-xtensa.org \
    --cc=monstr@monstr.eu \
    --cc=uclinux-h8-devel@lists.sourceforge.jp \
    /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.
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).