[075/262] kmod: prevent kmod_loop_msg overflow in __request_module()

[Greg KH]

3.0-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jiri Kosina <jkosina@xxxxxxx>

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@xxxxxxx>
Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 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;
 	}


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