Messages in this thread | | | From | Andi Kleen <> | Subject | Re: [PATCH] x86, mpx: Ensure unused arguments of prctl() MPX requests are 0 | Date | Fri, 09 Jan 2015 09:25:51 -0800 |
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"Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com> writes:
> From: Michael Kerrisk <mtk.manpages@gmail.com> > > commit fe8c7f5cbf91124987106faa3bdf0c8b955c4cf7 added two new prctl() > operations, PR_MPX_ENABLE_MANAGEMENT and PR_MPX_DISABLE_MANAGEMENT. > However, no checks were included to ensure that unused arguments > are zero, as is done in many existing prctl()s and as should be > done for all new prctl()s. This patch adds the required checks.
This will break the existing gcc run time, which doesn't zero these arguments.
-ANdi
> > Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> > --- > kernel/sys.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/kernel/sys.c b/kernel/sys.c > index a8c9f5a..ea9c881 100644 > --- a/kernel/sys.c > +++ b/kernel/sys.c > @@ -2210,9 +2210,13 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, > up_write(&me->mm->mmap_sem); > break; > case PR_MPX_ENABLE_MANAGEMENT: > + if (arg2 || arg3 || arg4 || arg5) > + return -EINVAL; > error = MPX_ENABLE_MANAGEMENT(me); > break; > case PR_MPX_DISABLE_MANAGEMENT: > + if (arg2 || arg3 || arg4 || arg5) > + return -EINVAL; > error = MPX_DISABLE_MANAGEMENT(me); > break; > default: > -- > 1.9.3
-- ak@linux.intel.com -- Speaking for myself only
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