Re: [PATCH 5/5] sh, hw_breakpoints: Fix racy access to ptrace breakpoints

From: Paul Mundt
Date: Mon Apr 11 2011 - 12:28:56 EST

On Fri, Apr 08, 2011 at 07:34:27PM +0200, Frederic Weisbecker wrote:
> While the tracer accesses ptrace breakpoints, the child task may
> concurrently exit due to a SIGKILL and thus release its breakpoints
> at the same time. We can then dereference some freed pointers.
> To fix this, hold a reference on the child breakpoints before
> manipulating them.
> Reported-by: Oleg Nesterov <oleg@xxxxxxxxxx>
> Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
> Cc: Ingo Molnar <mingo@xxxxxxx>
> Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
> Cc: Will Deacon <will.deacon@xxxxxxx>
> Cc: Prasad <prasad@xxxxxxxxxxxxxxxxxx>
> Cc: Paul Mundt <lethal@xxxxxxxxxxxx>

Acked-by: Paul Mundt <lethal@xxxxxxxxxxxx>
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at