lkml.org 
[lkml]   [2012]   [Dec]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [ 09/56] x86-32: Fix invalid stack address while in softirq
On Fri, Nov 30, 2012 at 10:55:01AM -0800, Greg Kroah-Hartman wrote:
> 3.4-stable review patch. If anyone has any objections, please let me know.
>
> ------------------
>
> From: Robert Richter <robert.richter@amd.com>
>
> commit 1022623842cb72ee4d0dbf02f6937f38c92c3f41 upstream.
>
> In 32 bit the stack address provided by kernel_stack_pointer() may
> point to an invalid range causing NULL pointer access or page faults
> while in NMI (see trace below). This happens if called in softirq
> context and if the stack is empty. The address at &regs->sp is then
> out of range.
>
> Fixing this by checking if regs and &regs->sp are in the same stack
> context. Otherwise return the previous stack pointer stored in struct
> thread_info. If that address is invalid too, return address of regs.
>

This also makes latest 3.4.y build fail with oprofile on i386, needs
also EXPORT_SYMBOL for kernel_stack_pointer (commit
cb57a2b4cff7edf2a4e32c0163200e9434807e0a)

--
[]'s
Herton


\
 
 \ /
  Last update: 2012-12-05 08:02    [W:0.826 / U:0.144 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site