| From 37252db6aa576c34fd794a5a54fb32d7a8b3a07a Mon Sep 17 00:00:00 2001 |
| From: Jiri Kosina <jkosina@suse.cz> |
| Date: Wed, 26 Oct 2011 13:10:39 +1030 |
| Subject: kmod: prevent kmod_loop_msg overflow in __request_module() |
| |
| From: Jiri Kosina <jkosina@suse.cz> |
| |
| commit 37252db6aa576c34fd794a5a54fb32d7a8b3a07a upstream. |
| |
| 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> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| kernel/kmod.c | 4 +++- |
| 1 file changed, 3 insertions(+), 1 deletion(-) |
| |
| --- a/kernel/kmod.c |
| +++ b/kernel/kmod.c |
| @@ -114,10 +114,12 @@ int __request_module(bool wait, const ch |
| 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; |
| } |