From 4444d852a99b8f0310f369da8473ec3639e380a7 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 14 May 2015 15:42:40 -0700 Subject: [PATCH] rcutorture: Check nfakewriters parameter Currently, a negative value for rcutorture.nfakewriters= can cause rcutorture to pass a negative size to the memory allocator, which is not really a particularly good thing to do. This commit therefore adds bounds checking to this parameter, so that values that are less than or equal to zero disable fake writing. Signed-off-by: Paul E. McKenney --- kernel/rcu/rcutorture.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 7e29a3266139..2cbe569ac5dd 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1786,12 +1786,15 @@ rcu_torture_init(void) writer_task); if (firsterr) goto unwind; - fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), - GFP_KERNEL); - if (fakewriter_tasks == NULL) { - VERBOSE_TOROUT_ERRSTRING("out of memory"); - firsterr = -ENOMEM; - goto unwind; + if (nfakewriters > 0) { + fakewriter_tasks = kzalloc(nfakewriters * + sizeof(fakewriter_tasks[0]), + GFP_KERNEL); + if (fakewriter_tasks == NULL) { + VERBOSE_TOROUT_ERRSTRING("out of memory"); + firsterr = -ENOMEM; + goto unwind; + } } for (i = 0; i < nfakewriters; i++) { firsterr = torture_create_kthread(rcu_torture_fakewriter, -- 2.39.5