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  1. 11 Feb, 2009 4 commits
  3. 09 Feb, 2009 4 commits
    • Ingo Molnar's avatar
      x86, pgtable.h: fix 2-level 32-bit build · c47c1b1f
      Ingo Molnar authored 
      - pmd_flags() needs to be available on 2-levels too
- provide pud_large() wrapper as well
- include page.h - it provides basic types relied on by pgtable.h
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      c47c1b1f
    • Ingo Molnar's avatar
      x86, pgtable.h: macro-ify *_page() methods · e5f7f202
      Ingo Molnar authored 
      The p?d_page() methods still rely on highlevel types and methods:

In file included from arch/x86/kernel/early_printk.c:18:
/home/mingo/tip/arch/x86/include/asm/pgtable.h: In function ‘pmd_page’:
/home/mingo/tip/arch/x86/include/asm/pgtable.h:516: error: implicit declaration of function ‘__pfn_to_section’
/home/mingo/tip/arch/x86/include/asm/pgtable.h:516: error: initialization makes pointer from integer without a cast
/home/mingo/tip/arch/x86/include/asm/pgtable.h:516: error: implicit declaration of function ‘__section_mem_map_addr’
/home/mingo/tip/arch/x86/include/asm/pgtable.h:516: error: return makes pointer from integer without a cast

So convert them to macros and document the type dependency.
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      e5f7f202
    • Ingo Molnar's avatar
      x86: early_printk.c - fix pgtable.h unification fallout · 726c0d95
      Ingo Molnar authored 
       arch/x86/kernel/early_printk.c: In function ‘early_dbgp_init’:
 arch/x86/kernel/early_printk.c:827: error: ‘PAGE_KERNEL_NOCACHE’ undeclared (first use in this function)
 arch/x86/kernel/early_printk.c:827: error: (Each undeclared identifier is reported only once
 arch/x86/kernel/early_printk.c:827: error: for each function it appears in.)
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      726c0d95
    • Ingo Molnar's avatar
      Merge branch 'jsgf/x86/unify' of... · 790c7ebb
      Ingo Molnar authored 
      Merge branch 'jsgf/x86/unify' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen into x86/headers
      790c7ebb
  5. 08 Feb, 2009 11 commits
  7. 07 Feb, 2009 18 commits
  9. 06 Feb, 2009 3 commits
    • Jeremy Fitzhardinge's avatar
      x86: Fix compile error in arch/x86/kernel/early_printk.c · fb08b20f
      Jeremy Fitzhardinge authored 
      Fix compile problem:

  CC      arch/x86/kernel/early_printk.o
In file included from /home/jeremy/hg/xen/paravirt/linux/arch/x86/kernel/early_printk.c:17:
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h: In function 'pmd_page':
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h:516: error: implicit declaration of function '__pfn_to_section'
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h:516: warning: initialization makes pointer from integer without a cast
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h:516: error: implicit declaration of function '__section_mem_map_addr'
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h:516: warning: return makes pointer from integer without a cast
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h: In function 'pud_page':
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h:586: warning: initialization makes pointer from integer without a cast
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h:586: warning: return makes pointer from integer without a cast
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h: In function 'pgd_page':
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h:625: warning: initialization makes pointer from integer without a cast
/home/jeremy/hg/xen/paravirt/linux/arch/x86/include/asm/pgtable.h:625: warning: return makes pointer from integer without a cast

This is a cycling dependency between asm/pgtable.h and linux/mmzone.h
when using CONFIG_SPARSEMEM.  Rather than hacking up the headers some
more, remove asm/pgtable.h, since early_printk.c doesn't actually need
it.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      fb08b20f
    • David Howells's avatar
      CRED: Fix SUID exec regression · 0bf2f3ae
      David Howells authored 
      The patch:

	commit a6f76f23
	CRED: Make execve() take advantage of copy-on-write credentials

moved the place in which the 'safeness' of a SUID/SGID exec was performed to
before de_thread() was called.  This means that LSM_UNSAFE_SHARE is now
calculated incorrectly.  This flag is set if any of the usage counts for
fs_struct, files_struct and sighand_struct are greater than 1 at the time the
determination is made.  All of which are true for threads created by the
pthread library.

However, since we wish to make the security calculation before irrevocably
damaging the process so that we can return it an error code in the case where
we decide we want to reject the exec request on this basis, we have to make the
determination before calling de_thread().

So, instead, we count up the number of threads (CLONE_THREAD) that are sharing
our fs_struct (CLONE_FS), files_struct (CLONE_FILES) and sighand_structs
(CLONE_SIGHAND/CLONE_THREAD) with us.  These will be killed by de_thread() and
so can be discounted by check_unsafe_exec().

We do have to be careful because CLONE_THREAD does not imply FS or FILES.

We _assume_ that there will be no extra references to these structs held by the
threads we're going to kill.

This can be tested with the attached pair of programs.  Build the two programs
using the Makefile supplied, and run ./test1 as a non-root user.  If
successful, you should see something like:

	[dhowells@andromeda tmp]$ ./test1
	--TEST1--
	uid=4043, euid=4043 suid=4043
	exec ./test2
	--TEST2--
	uid=4043, euid=0 suid=0
	SUCCESS - Correct effective user ID

and if unsuccessful, something like:

	[dhowells@andromeda tmp]$ ./test1
	--TEST1--
	uid=4043, euid=4043 suid=4043
	exec ./test2
	--TEST2--
	uid=4043, euid=4043 suid=4043
	ERROR - Incorrect effective user ID!

The non-root user ID you see will depend on the user you run as.

[test1.c]
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>

static void *thread_func(void *arg)
{
	while (1) {}
}

int main(int argc, char **argv)
{
	pthread_t tid;
	uid_t uid, euid, suid;

	printf("--TEST1--\n");
	getresuid(&uid, &euid, &suid);
	printf("uid=%d, euid=%d suid=%d\n", uid, euid, suid);

	if (pthread_create(&tid, NULL, thread_func, NULL) < 0) {
		perror("pthread_create");
		exit(1);
	}

	printf("exec ./test2\n");
	execlp("./test2", "test2", NULL);
	perror("./test2");
	_exit(1);
}

[test2.c]
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char **argv)
{
	uid_t uid, euid, suid;

	getresuid(&uid, &euid, &suid);
	printf("--TEST2--\n");
	printf("uid=%d, euid=%d suid=%d\n", uid, euid, suid);

	if (euid != 0) {
		fprintf(stderr, "ERROR - Incorrect effective user ID!\n");
		exit(1);
	}
	printf("SUCCESS - Correct effective user ID\n");
	exit(0);
}

[Makefile]
CFLAGS = -D_GNU_SOURCE -Wall -Werror -Wunused
all: test1 test2

test1: test1.c
	gcc $(CFLAGS) -o test1 test1.c -lpthread

test2: test2.c
	gcc $(CFLAGS) -o test2 test2.c
	sudo chown root.root test2
	sudo chmod +s test2
Reported-by: default avatarDavid Smith <dsmith@redhat.com>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Acked-by: default avatarDavid Smith <dsmith@redhat.com>
Signed-off-by: default avatarJames Morris <jmorris@namei.org>
      0bf2f3ae
    • Dave Kleikamp's avatar
      vfs: Don't call attach_nobh_buffers() with an empty list · d4cf109f
      Dave Kleikamp authored 
      This is a modification of a patch by Bill Pemberton <wfp5p@virginia.edu>

nobh_write_end() could call attach_nobh_buffers() with head == NULL.
This would result in a trap when attach_nobh_buffers() attempted to
access bh->b_this_page.

This can be illustrated by running the writev01 testcase from LTP on jfs.

This error was introduced by commit 5b41e74a "vfs: fix data leak in
nobh_write_end()".  That patch did not take into account that if
PageMappedToDisk() is true upon entry to nobh_write_begin(), then no
buffers will be allocated for the page.  In that case, we won't have to
worry about a failed write leaving unitialized data in the page.

Of course, head != NULL implies !page_has_buffers(page), so no need to
test both.
Signed-off-by: default avatarDave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Dmitri Monakhov <dmonakhov@openvz.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d4cf109f
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