Commit ac84aa2b authored Jul 06, 2012 by Naveen N. Rao Committed by Benjamin Herrenschmidt Jul 11, 2012

powerpc/hw_breakpoints: Fix incorrect pointer access



If arch_validate_hwbkpt_settings() fails, bp->ctx won't be valid and the
kernel panics. Add a check to fix this.

Reported-by: Edjunior Barbosa Machado <emachado@linux.vnet.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

parent 1d5a436d

arch/powerpc/kernel/hw_breakpoint.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -111,7 +111,7 @@ void arch_unregister_hw_breakpoint(struct perf_event *bp)
		* and the single_step_dabr_instruction(), then cleanup the breakpoint
		* restoration variables to prevent dangling pointers.
		*/
		if (bp->ctx->task)
		if (bp->ctx && bp->ctx->task)
		bp->ctx->task->thread.last_hit_ubp = NULL;
		}