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 16/17] binfmt_flat: don't offset the data start
Date: Thu, 13 Jun 2019 09:09:02 +0200 [thread overview]
Message-ID: <20190613070903.17214-17-hch@lst.de> (raw)
In-Reply-To: <20190613070903.17214-1-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 ccd9843e979e..80d902fb46e3 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -573,7 +573,7 @@ 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);
@@ -587,9 +587,7 @@ 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);
@@ -619,7 +617,7 @@ 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);
@@ -634,9 +632,7 @@ 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));
@@ -653,8 +649,9 @@ 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.
@@ -710,8 +707,7 @@ 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
next prev parent reply other threads:[~2019-06-13 16:38 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-13 7:08 binfmt_flat cleanups and RISC-V support v2 Christoph Hellwig
2019-06-13 7:08 ` [PATCH 01/17] binfmt_flat: remove flat_reloc_valid Christoph Hellwig
2019-06-13 7:08 ` [PATCH 02/17] binfmt_flat: remove flat_set_persistent Christoph Hellwig
2019-06-13 7:08 ` [PATCH 03/17] binfmt_flat: provide a default version of flat_get_relocate_addr Christoph Hellwig
2019-06-13 7:08 ` [PATCH 04/17] binfmt_flat: remove flat_old_ram_flag Christoph Hellwig
2019-06-13 7:08 ` [PATCH 05/17] binfmt_flat: replace flat_argvp_envp_on_stack with a Kconfig variable Christoph Hellwig
2019-06-13 7:08 ` [PATCH 06/17] binfmt_flat: remove the uapi <linux/flat.h> header Christoph Hellwig
2019-06-13 7:08 ` [PATCH 07/17] binfmt_flat: remove the unused OLD_FLAT_FLAG_RAM definition Christoph Hellwig
2019-06-13 7:08 ` [PATCH 08/17] binfmt_flat: consolidate two version of flat_v2_reloc_t Christoph Hellwig
2019-06-25 22:29 ` Al Viro
2019-06-26 7:23 ` Greg Ungerer
2019-06-26 8:18 ` Geert Uytterhoeven
2019-06-26 12:14 ` Greg Ungerer
2019-06-13 7:08 ` [PATCH 09/17] binfmt_flat: use fixed size type for the on-disk format Christoph Hellwig
2019-06-13 7:08 ` [PATCH 10/17] binfmt_flat: add endianess annotations Christoph Hellwig
2019-06-13 7:08 ` [PATCH 11/17] binfmt_flat: add a ARCH_HAS_BINFMT_FLAT option Christoph Hellwig
2019-06-13 7:08 ` [PATCH 12/17] binfmt_flat: make support for old format binaries optional Christoph Hellwig
2019-06-13 7:08 ` [PATCH 13/17] binfmt_flat: provide an asm-generic/flat.h Christoph Hellwig
2019-06-13 7:09 ` [PATCH 14/17] binfmt_flat: remove the persistent argument from flat_get_addr_from_rp Christoph Hellwig
2019-06-13 7:09 ` [PATCH 15/17] binfmt_flat: move the MAX_SHARED_LIBS definition to binfmt_flat.c Christoph Hellwig
2019-06-14 8:35 ` Sergei Shtylyov
2019-06-13 7:09 ` Christoph Hellwig [this message]
2019-06-13 7:09 ` [PATCH 17/17] riscv: add binfmt_flat support Christoph Hellwig
2019-06-13 23:38 ` binfmt_flat cleanups and RISC-V support v2 Greg Ungerer
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=20190613070903.17214-17-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
all inboxes | Powered by JetHome®