[PATCH] PPC Hardware Breakpoints: Fix incorrect pointer access
From: Naveen N. Rao <hidden>
Date: 2012-07-06 11:31:17
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 <redacted> Signed-off-by: Naveen N. Rao <redacted> --- arch/powerpc/kernel/hw_breakpoint.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c
index 2bc0584..f3a82dd 100644
--- a/arch/powerpc/kernel/hw_breakpoint.c
+++ b/arch/powerpc/kernel/hw_breakpoint.c@@ -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; }