linux/arch
Arjan van de Ven ae531c26c5 x86: introduce /dev/mem restrictions with a config option
This patch introduces a restriction on /dev/mem: Only non-memory can be
read or written unless the newly introduced config option is set.

The X server needs access to /dev/mem for the PCI space, but it doesn't need
access to memory; both the file permissions and SELinux permissions of /dev/mem
just make X effectively super-super powerful. With the exception of the
BIOS area, there's just no valid app that uses /dev/mem on actual memory.
Other popular users of /dev/mem are rootkits and the like.
(note: mmap access of memory via /dev/mem was already not allowed since
a really long time)

People who want to use /dev/mem for kernel debugging can enable the config
option.

The restrictions of this patch have been in the Fedora and RHEL kernels for
at least 4 years without any problems.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:40:47 +02:00
..
alpha PCI: alpha: use generic pci_enable_resources() 2008-04-20 21:47:04 -07:00
arm Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/juhl/trivial 2008-04-21 16:36:46 -07:00
avr32 avr32: Add hardware power-down function call 2008-04-19 20:40:11 -04:00
blackfin [BLACKFIN] minor irq handler cleanups 2008-04-20 18:45:27 -04:00
cris Generic semaphore implementation 2008-04-17 10:42:34 -04:00
frv frv: unexport kmap_atomic_to_page 2008-04-21 16:03:13 -07:00
h8300 Generic semaphore implementation 2008-04-17 10:42:34 -04:00
ia64 [IA64] move XP and XPC to drivers/misc/sgi-xp 2008-04-22 15:08:17 -07:00
m32r Generic semaphore implementation 2008-04-17 10:42:34 -04:00
m68k arch: Remove unnecessary inclusions of asm/semaphore.h 2008-04-18 22:14:49 -04:00
m68knommu Generic semaphore implementation 2008-04-17 10:42:34 -04:00
mips arch: Remove unnecessary inclusions of asm/semaphore.h 2008-04-18 22:14:49 -04:00
mn10300 PCI: remove initial bios sort of PCI devices on x86 2008-04-20 21:46:58 -07:00
parisc Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/pci-2.6 2008-04-21 15:58:35 -07:00
powerpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/pci-2.6 2008-04-21 15:58:35 -07:00
ppc Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/pci-2.6 2008-04-21 15:58:35 -07:00
s390 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2008-04-21 15:57:09 -07:00
sh Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/pci-2.6 2008-04-21 15:58:35 -07:00
sparc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6 2008-04-21 17:20:53 -07:00
sparc64 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6 2008-04-21 17:20:53 -07:00
um Generic semaphore implementation 2008-04-17 10:42:34 -04:00
v850 arch: Remove unnecessary inclusions of asm/semaphore.h 2008-04-18 22:14:49 -04:00
x86 x86: introduce /dev/mem restrictions with a config option 2008-04-24 23:40:47 +02:00
xtensa Generic semaphore implementation 2008-04-17 10:42:34 -04:00
.gitignore
Kconfig Kprobes: indicate kretprobe support in Kconfig 2008-03-04 16:35:11 -08:00