Commit 37252db6 authored Oct 26, 2011 by Jiri Kosina Committed by Rusty Russell Oct 26, 2011

kmod: prevent kmod_loop_msg overflow in __request_module()



Due to post-increment in condition of kmod_loop_msg in __request_module(),
the system log can be spammed by much more than 5 instances of the 'runaway
loop' message if the number of events triggering it makes the kmod_loop_msg
to overflow.

Fix that by making sure we never increment it past the threshold.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
CC: stable@kernel.org

parent c3b92c87

kernel/kmod.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -114,10 +114,12 @@ int __request_module(bool wait, const char *fmt, ...)
		atomic_inc(&kmod_concurrent);
		if (atomic_read(&kmod_concurrent) > max_modprobes) {
		/* We may be blaming an innocent here, but unlikely */
		if (kmod_loop_msg++ < 5)
		if (kmod_loop_msg < 5) {
		printk(KERN_ERR
		"request_module: runaway loop modprobe %s\n",
		module_name);
		kmod_loop_msg++;
		}
		atomic_dec(&kmod_concurrent);
		return -ENOMEM;
		}