commit: 66832eb4baaaa9abe4c993ddf9113a79e39b9915 From: Oleg Nesterov <[email protected]> Date: Tue, 18 Jan 2011 17:10:32 +0100 Subject: [PATCH] perf: Validate cpu early in perf_event_alloc()
Starting from perf_event_alloc()->perf_init_event(), the kernel assumes that event->cpu is either -1 or the valid CPU number. Change perf_event_alloc() to validate this argument early. This also means we can remove the similar check in find_get_context(). Signed-off-by: Oleg Nesterov <[email protected]> Acked-by: Peter Zijlstra <[email protected]> Cc: Alan Stern <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Prasad <[email protected]> Cc: Roland McGrath <[email protected]> Cc: [email protected] Cc: [email protected] LKML-Reference: <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> --- kernel/perf_event.c | 10 ++++++---- 1 files changed, 6 insertions(+), 4 deletions(-) diff --git a/kernel/perf_event.c b/kernel/perf_event.c index a962b19..67d9bd7 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -2233,9 +2233,6 @@ find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) return ERR_PTR(-EACCES); - if (cpu < 0 || cpu >= nr_cpumask_bits) - return ERR_PTR(-EINVAL); - /* * We could be clever and allow to attach a event to an * offline CPU and activate it when the CPU comes up, but @@ -5541,6 +5538,11 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, struct hw_perf_event *hwc; long err; + if ((unsigned)cpu >= nr_cpu_ids) { + if (!task || cpu != -1) + return ERR_PTR(-EINVAL); + } + event = kzalloc(sizeof(*event), GFP_KERNEL); if (!event) return ERR_PTR(-ENOMEM); @@ -5589,7 +5591,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, if (!overflow_handler && parent_event) overflow_handler = parent_event->overflow_handler; - + event->overflow_handler = overflow_handler; if (attr->disabled) _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
