From: Baptiste Lepers baptiste.lepers@gmail.com
stable inclusion from stable-5.10.68 commit c5102ced8ac0a106182332de15ea2b2920581811 bugzilla: 182671 https://gitee.com/openeuler/kernel/issues/I4EWUH
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
--------------------------------
commit b89a05b21f46150ac10a962aa50109250b56b03b upstream.
In perf_event_addr_filters_apply, the task associated with the event (event->ctx->task) is read using READ_ONCE at the beginning of the function, checked, and then re-read from event->ctx->task, voiding all guarantees of the checks. Reuse the value that was read by READ_ONCE to ensure the consistency of the task struct throughout the function.
Fixes: 375637bc52495 ("perf/core: Introduce address range filtering") Signed-off-by: Baptiste Lepers baptiste.lepers@gmail.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Link: https://lkml.kernel.org/r/20210906015310.12802-1-baptiste.lepers@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Chen Jun chenjun102@huawei.com Acked-by: Weilong Chen chenweilong@huawei.com
Signed-off-by: Chen Jun chenjun102@huawei.com --- kernel/events/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c index 7e0fdc19043e..c677f934353a 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -9973,7 +9973,7 @@ static void perf_event_addr_filters_apply(struct perf_event *event) return;
if (ifh->nr_file_filters) { - mm = get_task_mm(event->ctx->task); + mm = get_task_mm(task); if (!mm) goto restart;