linux-toradex.git/arch/parisc/kernel/traps.c, branch v2.6.27.14

parisc: fix kernel crash when unwinding a userspace process

2008-12-05T18:55:11+00:00

commit 7a3f5134a8f5bd7fa38b5645eef05e8a4eb62951 upstream.

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 
Cc: Grant Grundler 
Cc: Matthew Wilcox 
Signed-off-by: Andrew Morton 
Signed-off-by: Kyle McMartin 
Signed-off-by: Greg Kroah-Hartman

parisc: replace remaining FUNCTION occurrences

2008-05-15T14:38:54+00:00

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison 
Cc: Kyle McMartin 
Cc: Matthew Wilcox 
Cc: Grant Grundler 
Signed-off-by: Andrew Morton 
Signed-off-by: Kyle McMartin

[PARISC] clean up show_stack

2008-03-16T02:12:15+00:00

When we show_regs, we obviously have a struct pt_regs of the calling
frame. Use these in show_stack so we don't have the entire bogus call trace
up to the show_stack call.

Signed-off-by: Kyle McMartin

[PARISC] dump_stack in show_regs

2008-03-16T02:12:01+00:00

Originally, show_stack was used in BUG() output. However, a recent commit
changed it to print register state (no idea what that's supposed to help,
really...) and parisc was missing a backtrace because of it.

Signed-off-by: Kyle McMartin

Use helpers to obtain task pid in printks (arch code)

2007-10-19T18:53:43+00:00

One of the easiest things to isolate is the pid printed in kernel log.
There was a patch, that made this for arch-independent code, this one makes
so for arch/xxx files.

It took some time to cross-compile it, but hopefully these are all the
printks in arch code.

Signed-off-by: Alexey Dobriyan 
Signed-off-by: Pavel Emelyanov 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Report that kernel is tainted if there was an OOPS

2007-07-17T17:23:02+00:00

If the kernel OOPSed or BUGed then it probably should be considered as
tainted.  Thus, all subsequent OOPSes and SysRq dumps will report the
tainted kernel.  This saves a lot of time explaining oddities in the
calltraces.

Signed-off-by: Pavel Emelianov 
Acked-by: Randy Dunlap 
Cc: 
Signed-off-by: Andrew Morton 
[ Added parisc patch from Matthew Wilson  -Linus ]
Signed-off-by: Linus Torvalds

generic bug: use show_regs() instead of dump_stack()

2007-07-16T16:05:51+00:00

The current generic bug implementation has a call to dump_stack() in case a
WARN_ON(whatever) gets hit.  Since report_bug(), which calls dump_stack(),
gets called from an exception handler we can do better: just pass the
pt_regs structure to report_bug() and pass it to show_regs() in case of a
warning.  This will give more debug informations like register contents,
etc...  In addition this avoids some pointless lines that dump_stack()
emits, since it includes a stack backtrace of the exception handler which
is of no interest in case of a warning.  E.g.  on s390 the following lines
are currently always present in a stack backtrace if dump_stack() gets
called from report_bug():

 [<000000000001517a>] show_trace+0x92/0xe8)
 [<0000000000015270>] show_stack+0xa0/0xd0
 [<00000000000152ce>] dump_stack+0x2e/0x3c
 [<0000000000195450>] report_bug+0x98/0xf8
 [<0000000000016cc8>] illegal_op+0x1fc/0x21c
 [<00000000000227d6>] sysc_return+0x0/0x10

Acked-by: Jeremy Fitzhardinge 
Acked-by: Haavard Skinnemoen 
Cc: Andi Kleen 
Cc: Kyle McMartin 
Cc: Paul Mackerras 
Cc: Paul Mundt 
Cc: Martin Schwidefsky 
Signed-off-by: Heiko Carstens 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PARISC] Fix kernel panic in check_ivt

2007-06-04T06:26:52+00:00

check_ivt had some seriously broken code wrt function pointers on
parisc64. Instead of referencing the hpmc code via a function pointer,
export symbols and reference it as a const array.

Thanks to jda for pointing out the broken 64-bit func ptr handling.

Signed-off-by: Kyle McMartin

[PARISC] spelling fixes: arch/parisc/

2007-05-23T02:52:16+00:00

Spelling fixes in arch/parisc/.

Signed-off-by: Simon Arlott 
Acked-by: Grant Grundler 
Signed-off-by: Kyle McMartin

header cleaning: don't include smp_lock.h when not used

2007-05-08T18:15:07+00:00

Remove includes of  where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds