From b96bbdde19cc56f288372d25fd5ea7af04fc1271 Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Tue, 19 Apr 2016 21:17:25 -0700 Subject: [PATCH] locking/pvqspinlock: Robustify init_qspinlock_stat() Specifically around the debugfs file creation calls, I have no idea if they could ever possibly fail, but this is core code (debug aside) so lets at least check the return value and inform anything fishy. Signed-off-by: Davidlohr Bueso Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Waiman Long Cc: Andrew Morton Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20160420041725.GC3472@linux-uzut.site Signed-off-by: Ingo Molnar --- kernel/locking/qspinlock_stat.h | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/kernel/locking/qspinlock_stat.h b/kernel/locking/qspinlock_stat.h index 72722334237a..22e025309845 100644 --- a/kernel/locking/qspinlock_stat.h +++ b/kernel/locking/qspinlock_stat.h @@ -212,10 +212,8 @@ static int __init init_qspinlock_stat(void) struct dentry *d_qstat = debugfs_create_dir("qlockstat", NULL); int i; - if (!d_qstat) { - pr_warn("Could not create 'qlockstat' debugfs directory\n"); - return 0; - } + if (!d_qstat) + goto out; /* * Create the debugfs files @@ -225,12 +223,20 @@ static int __init init_qspinlock_stat(void) * performance. */ for (i = 0; i < qstat_num; i++) - debugfs_create_file(qstat_names[i], 0400, d_qstat, - (void *)(long)i, &fops_qstat); + if (!debugfs_create_file(qstat_names[i], 0400, d_qstat, + (void *)(long)i, &fops_qstat)) + goto fail_undo; + + if (!debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat, + (void *)(long)qstat_reset_cnts, &fops_qstat)) + goto fail_undo; - debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat, - (void *)(long)qstat_reset_cnts, &fops_qstat); return 0; +fail_undo: + debugfs_remove_recursive(d_qstat); +out: + pr_warn("Could not create 'qlockstat' debugfs entries\n"); + return -ENOMEM; } fs_initcall(init_qspinlock_stat); -- 2.39.5