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  1. 09 Feb, 2009 1 commit
  3. 08 Feb, 2009 11 commits
  5. 07 Feb, 2009 18 commits
  7. 06 Feb, 2009 10 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
    • Jeremy Fitzhardinge's avatar
      x86: asm/io.h: unify ioremap prototypes · 133822c5
      Jeremy Fitzhardinge authored 
      Impact: unify identical code

asm/io_32.h and _64.h have identical prototypes for the ioremap family
of functions.  The 32-bit header had a more descriptive comment.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      133822c5
    • Jeremy Fitzhardinge's avatar
      x86: asm/io.h: unify virt_to_phys/phys_to_virt · 976e8f67
      Jeremy Fitzhardinge authored 
      Impact: unify identical code

asm/io_32.h and _64.h has functionally identical definitions for
virt_to_phys, phys_to_virt, page_to_phys, and the isa_* variants, so
just unify them.

The only slightly functional change is using phys_addr_t for the
physical address argument and return val.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      976e8f67
    • Jeremy Fitzhardinge's avatar
      x86: make pgd/pud/pmd/pte_none consistent · 26c8e317
      Jeremy Fitzhardinge authored 
      The _none test is done differently for every level of the pagetable.
Standardize them by:

 1: Use the native_X_val to extract the raw entry, with no need to go
    via paravirt_ops, diff -r 1d0646d0d319 arch/x86/include/asm/pgtable.h, and
 2: Compare with 0 rather than using a boolean !, since they are actually values
    and not booleans.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      26c8e317
    • Jeremy Fitzhardinge's avatar
      x86: add and use pgd/pud/pmd_flags · 18a7a199
      Jeremy Fitzhardinge authored 
      Add pgd/pud/pmd_flags which are analogous to pte_flags, and use them
where-ever we only care about testing the flags portions of the
respective entries.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      18a7a199
    • Jeremy Fitzhardinge's avatar
      x86: unify io_remap_pfn_range · 6cf71500
      Jeremy Fitzhardinge authored 
      Impact: cleanup

Unify io_remap_pfn_range.  Don't demacro yet.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      6cf71500
    • Jeremy Fitzhardinge's avatar
      x86: unify pgd_none · 7325cc2e
      Jeremy Fitzhardinge authored 
      Impact: cleanup

Unify and demacro pgd_none.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      7325cc2e
    • Jeremy Fitzhardinge's avatar
      x86: unify pud_none · deb79cfb
      Jeremy Fitzhardinge authored 
      Impact: cleanup

Unify and demacro pud_none.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      deb79cfb
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