From c7718e5c76d49b5bb394265383ae51f766d5dd3a Mon Sep 17 00:00:00 2001 From: Jeff Xie Date: Sun, 25 Aug 2024 21:19:11 +0800 Subject: [PATCH] genirq/proc: Correctly set file permissions for affinity control files The kernel already knows at the time of interrupt allocation whether affinity of an interrupt can be controlled by userspace or not. It still creates all related procfs control files with read/write permissions. That's inconsistent and non-intuitive for system administrators and tools. Therefore set the file permissions to read-only for such interrupts. [ tglx: Massage change log, fixed UP build ] Signed-off-by: Jeff Xie Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20240825131911.107119-1-jeff.xie@linux.dev --- kernel/irq/proc.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 8cccdf40725a..9b3b12ad5dda 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -362,8 +362,13 @@ void register_irq_proc(unsigned int irq, struct irq_desc *desc) goto out_unlock; #ifdef CONFIG_SMP + umode_t umode = S_IRUGO; + + if (irq_can_set_affinity_usr(desc->irq_data.irq)) + umode |= S_IWUSR; + /* create /proc/irq//smp_affinity */ - proc_create_data("smp_affinity", 0644, desc->dir, + proc_create_data("smp_affinity", umode, desc->dir, &irq_affinity_proc_ops, irqp); /* create /proc/irq//affinity_hint */ @@ -371,7 +376,7 @@ void register_irq_proc(unsigned int irq, struct irq_desc *desc) irq_affinity_hint_proc_show, irqp); /* create /proc/irq//smp_affinity_list */ - proc_create_data("smp_affinity_list", 0644, desc->dir, + proc_create_data("smp_affinity_list", umode, desc->dir, &irq_affinity_list_proc_ops, irqp); proc_create_single_data("node", 0444, desc->dir, irq_node_proc_show,