linux_dsm_epyc7002/include
Ingo Molnar e6e5494cb2 [PATCH] vdso: randomize the i386 vDSO by moving it into a vma
Move the i386 VDSO down into a vma and thus randomize it.

Besides the security implications, this feature also helps debuggers, which
can COW a vma-backed VDSO just like a normal DSO and can thus do
single-stepping and other debugging features.

It's good for hypervisors (Xen, VMWare) too, which typically live in the same
high-mapped address space as the VDSO, hence whenever the VDSO is used, they
get lots of guest pagefaults and have to fix such guest accesses up - which
slows things down instead of speeding things up (the primary purpose of the
VDSO).

There's a new CONFIG_COMPAT_VDSO (default=y) option, which provides support
for older glibcs that still rely on a prelinked high-mapped VDSO.  Newer
distributions (using glibc 2.3.3 or later) can turn this option off.  Turning
it off is also recommended for security reasons: attackers cannot use the
predictable high-mapped VDSO page as syscall trampoline anymore.

There is a new vdso=[0|1] boot option as well, and a runtime
/proc/sys/vm/vdso_enabled sysctl switch, that allows the VDSO to be turned
on/off.

(This version of the VDSO-randomization patch also has working ELF
coredumping, the previous patch crashed in the coredumping code.)

This code is a combined work of the exec-shield VDSO randomization
code and Gerd Hoffmann's hypervisor-centric VDSO patch. Rusty Russell
started this patch and i completed it.

[akpm@osdl.org: cleanups]
[akpm@osdl.org: compile fix]
[akpm@osdl.org: compile fix 2]
[akpm@osdl.org: compile fix 3]
[akpm@osdl.org: revernt MAXMEM change]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Cc: Gerd Hoffmann <kraxel@suse.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:38 -07:00
..
acpi Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2006-06-23 07:52:36 -07:00
asm-alpha [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-arm Merge master.kernel.org:/home/rmk/linux-2.6-arm 2006-06-26 15:01:05 -07:00
asm-arm26 [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-cris Remove unneeded _syscallX macros from user view in asm-*/unistd.h 2006-04-29 01:51:47 +01:00
asm-frv [PATCH] frv: clean frv unistd.h 2006-06-23 07:42:55 -07:00
asm-generic [PATCH] introduce WARN_ON_ONCE(cond) 2006-06-25 10:01:11 -07:00
asm-h8300 [PATCH] adjust handle_IRR_event() return type 2006-06-23 07:43:08 -07:00
asm-i386 [PATCH] vdso: randomize the i386 vDSO by moving it into a vma 2006-06-27 17:32:38 -07:00
asm-ia64 [PATCH] pgdat allocation and update for ia64 of memory hotplug: update pgdat address array 2006-06-27 17:32:37 -07:00
asm-m32r spelling fixes 2006-06-26 18:35:02 +02:00
asm-m68k [PATCH] m68k: convert VME irq code 2006-06-25 10:00:58 -07:00
asm-m68knommu [PATCH] m68knommu: use configurable RAM setup page_offset.h 2006-06-26 10:59:44 -07:00
asm-mips [PATCH] N32 sigset and __COMPAT_ENDIAN_SWAP__ 2006-06-25 10:01:15 -07:00
asm-parisc [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-powerpc [PATCH] Notify page fault call chain 2006-06-26 09:58:22 -07:00
asm-ppc [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-s390 [PATCH] Define __raw_get_cpu_var and use it 2006-06-25 10:01:01 -07:00
asm-sh [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-sh64 Remove unneeded _syscallX macros from user view in asm-*/unistd.h 2006-04-29 01:51:47 +01:00
asm-sparc [SPARC]: Add iomap interfaces. 2006-06-25 23:24:24 -07:00
asm-sparc64 Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6 2006-06-26 10:08:32 -07:00
asm-um Merge git://git.infradead.org/hdrcleanup-2.6 2006-06-20 15:10:08 -07:00
asm-v850 [PATCH] adjust handle_IRR_event() return type 2006-06-23 07:43:08 -07:00
asm-x86_64 [PATCH] x86: increase interrupt vector range 2006-06-27 17:32:37 -07:00
asm-xtensa [PATCH] xtensa: remove verify_area macros 2006-06-23 07:43:02 -07:00
keys [PATCH] keys: discard the contents of a key on revocation 2006-06-26 09:58:18 -07:00
linux [PATCH] vdso: randomize the i386 vDSO by moving it into a vma 2006-06-27 17:32:38 -07:00
math-emu
media V4L/DVB (4223): Add V4L2_CID_MPEG_STREAM_VBI_FMT control 2006-06-26 09:21:45 -03:00
mtd Merge git://git.infradead.org/hdrcleanup-2.6 2006-06-20 15:10:08 -07:00
net [TIPC]: Corrected potential misuse of tipc_media_addr structure. 2006-06-25 23:38:29 -07:00
pcmcia Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
rdma IB/uverbs: Don't serialize with ib_uverbs_idr_mutex 2006-06-17 20:44:49 -07:00
rxrpc
scsi Merge branch 'master' into upstream 2006-06-22 22:11:56 -04:00
sound V4L/DVB (4210b): git-dvb: tea575x-tuner build fix 2006-06-25 02:05:25 -03:00
video Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00