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5 commits

Author SHA1 Message Date
Julien Tinnes
f9fabcb58a personality: fix PER_CLEAR_ON_SETID
We have found that the current PER_CLEAR_ON_SETID mask on Linux doesn't
include neither ADDR_COMPAT_LAYOUT, nor MMAP_PAGE_ZERO.

The current mask is READ_IMPLIES_EXEC|ADDR_NO_RANDOMIZE.

We believe it is important to add MMAP_PAGE_ZERO, because by using this
personality it is possible to have the first page mapped inside a
process running as setuid root.  This could be used in those scenarios:

 - Exploiting a NULL pointer dereference issue in a setuid root binary
 - Bypassing the mmap_min_addr restrictions of the Linux kernel: by
   running a setuid binary that would drop privileges before giving us
   control back (for instance by loading a user-supplied library), we
   could get the first page mapped in a process we control.  By further
   using mremap and mprotect on this mapping, we can then completely
   bypass the mmap_min_addr restrictions.

Less importantly, we believe ADDR_COMPAT_LAYOUT should also be added
since on x86 32bits it will in practice disable most of the address
space layout randomization (only the stack will remain randomized).

Signed-off-by: Julien Tinnes <jt@cr0.org>
Signed-off-by: Tavis Ormandy <taviso@sdf.lonestar.org>
Cc: stable@kernel.org
Acked-by: Christoph Hellwig <hch@infradead.org>
Acked-by: Kees Cook <kees@ubuntu.com>
Acked-by: Eugene Teo <eugene@redhat.com>
[ Shortened lines and fixed whitespace as per Christophs' suggestion ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-12 12:21:33 -07:00
WANG Cong
ecd0fa9825 Remove the macro get_personality
Remove the macro get_personality, use ->personality instead.

Cc: Christoph Hellwig <hch@infradead.org
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Bryan Wu <bryan.wu@analog.com>
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:02 -07:00
Russell King
d8b295f290 [PATCH] Fix missing parens in set_personality()
If you call set_personality() with an expression such as:

	set_personality(foo ? PERS_FOO1 : PERS_FOO2);

then this evaluates to:

	((current->personality == foo ? PERS_FOO1 : PERS_FOO2) ? ...

which is obviously not the intended result.  Add the missing parents
to ensure this gets evaluated as expected:

	((current->personality == (foo ? PERS_FOO1 : PERS_FOO2)) ? ...

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-13 07:40:42 -08:00
Ralf Baechle
34e856e6a5 [PATCH] Make <linux/personality.h> userspace proof
<linux/personality.h> contains the constants for personality(2) but also
some defintions that are useless or even harmful in userspace such as the
personality() macro.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:35 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00