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Relax this to allow tasks running as unprivileged users with CAP_SYS_RESOURCE to be able to write to these files. Signed-off-by: Josh Hunt --- kernel/sched/psi.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index b1b00e9bd7ed..98ff7baf1ba8 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -1270,6 +1270,9 @@ static ssize_t psi_write(struct file *file, const char __user *user_buf, if (!nbytes) return -EINVAL; + if (!capable(CAP_SYS_RESOURCE)) + return -EPERM; + buf_size = min(nbytes, sizeof(buf)); if (copy_from_user(buf, user_buf, buf_size)) return -EFAULT; @@ -1353,9 +1356,9 @@ static int __init psi_proc_init(void) { if (psi_enable) { proc_mkdir("pressure", NULL); - proc_create("pressure/io", 0, NULL, &psi_io_proc_ops); - proc_create("pressure/memory", 0, NULL, &psi_memory_proc_ops); - proc_create("pressure/cpu", 0, NULL, &psi_cpu_proc_ops); + proc_create("pressure/io", 0666, NULL, &psi_io_proc_ops); + proc_create("pressure/memory", 0666, NULL, &psi_memory_proc_ops); + proc_create("pressure/cpu", 0666, NULL, &psi_cpu_proc_ops); } return 0; } -- 2.17.1