1
linux/arch
Helge Deller 7a3f5134a8 parisc: fix kernel crash when unwinding a userspace process
Any user on existing parisc 32- and 64bit-kernels can easily crash
the kernel and as such enforce a DSO.
A simple testcase is available here:
        http://gsyprf10.external.hp.com/~deller/crash.tgz

The problem is introduced by the fact, that the handle_interruption()
crash handler calls the show_regs() function, which in turn tries to
unwind the stack by calling parisc_show_stack().  Since the stack contains
userspace addresses, a try to unwind the stack is dangerous and useless
and leads to the crash.

The fix is trivial: For userspace processes
a) avoid to unwind the stack, and
b) avoid to resolve userspace addresses to kernel symbol names.

While touching this code, I converted print_symbol() to %pS
printk formats and made parisc_show_stack() static.

An initial patch for this was written by Kyle McMartin back in August:
http://marc.info/?l=linux-parisc&m=121805168830283&w=2

Compile and run-tested with a 64bit parisc kernel.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: <stable@kernel.org>		[2.6.25.x, 2.6.26.x, 2.6.27.x, earlier...]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-11-26 22:22:39 +00:00
..
alpha Merge branch 'v28-range-hrtimers-for-linus-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-23 10:53:02 -07:00
arm [ARM] 5330/1: mach-pxa: Fixup reset for systems using reboot=cold or other strings 2008-11-17 14:05:41 +00:00
avr32 Merge branches 'boards' and 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6 2008-10-23 15:24:10 +02:00
blackfin Blackfin arch: fix a broken define in dma-mapping 2008-11-18 17:48:22 +08:00
cris [CRIS] Remove links from CRIS build 2008-10-31 23:37:57 +01:00
frv container freezer: implement freezer cgroup subsystem 2008-10-20 08:52:34 -07:00
h8300 Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/dvrabel/uwb 2008-10-23 08:20:34 -07:00
ia64 [IA64] xen: fix xen_get_eflags. 2008-11-20 13:43:01 -08:00
m32r Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile 2008-10-23 10:05:40 -07:00
m68k m68k: Fix off-by-one in m68k_setup_user_interrupt() 2008-11-15 11:36:06 -08:00
m68knommu container freezer: implement freezer cgroup subsystem 2008-10-20 08:52:34 -07:00
mips MIPS: csrc-r4k: Fix declaration depending on the wrong CONFIG_ symbol. 2008-11-20 19:42:33 +00:00
mn10300 MN10300: Don't do misalignment handling for userspace 2008-11-12 10:41:18 -08:00
parisc parisc: fix kernel crash when unwinding a userspace process 2008-11-26 22:22:39 +00:00
powerpc powerpc: Update desktop/server defconfigs 2008-11-11 19:42:30 +11:00
s390 [S390] fix s390x_newuname 2008-11-14 18:18:55 +01:00
sh serial: sh-sci: Reorder the SCxTDR write after the TDxE clear. 2008-11-13 17:46:06 +09:00
sparc sparc64: wire up accept4() 2008-11-19 18:49:57 -08:00
sparc64 sparc64: wire up accept4() 2008-11-19 18:49:57 -08:00
um Merge git://git.kernel.org/pub/scm/linux/kernel/git/viro/bdev 2008-10-23 10:23:07 -07:00
x86 x86: Fix interrupt leak due to migration 2008-11-20 13:17:40 -08:00
xtensa Merge git://git.kernel.org/pub/scm/linux/kernel/git/czankel/xtensa-2.6 2008-10-23 09:16:56 -07:00
.gitignore
Kconfig Change UTF8 chars in Kconfig help text about Oprofile AMD barcelona 2008-10-27 19:15:39 +01:00