Bug 141545

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Description of problem:
klogd retrieves kernel printk messages and sends them to syslogd after
a little massaging. One of the massaging steps will turn an odd number
of percent signs into an even number of percents signs using a
non-reversible mechanism.

For example, if the kernel performs printk(KERN_INFO "%s\n", "%");,
the dmesg output buffer will properly show only a single % sign, while
the syslog log files will have %%.

Unfortunately, printking %% will also put %% into the syslog files.

Thus, the transormation in klogd is non-reversible -- it is no longer
clear how many percent signs there were in the kernel's output.

I recommend that klogd be modified to no longer massage the kernel
messages in non-reversible mechanisms. I expect a single % should work
fine so long as klogd doesn't do something fantastically stupid like
pass the kernel output to syslog() as the message format string.

Version-Release number of selected component (if applicable):
sysklogd-1.4.1-22

How reproducible:
Always

Steps to Reproduce:
1. Download and untar http://www.kernelnewbies.org/faq/sillymod.tar.gz
(very small "hello world" kernel module)
2. Apply the patch I will attach shortly (very simple, amends the
printk to include a single %)
3.  run the ./configure and make steps
4.  insmod ./sillymod.ko
5.  Check dmesg output versus /var/log/messages output
    

Actual Results:  dmesg will report:
Sillymod % loaded into 2.6.8-1.528.2.10.
tail /var/log/messages:
Dec  1 13:53:32 dhcp-246 kernel: Sillymod %% loaded into 2.6.8-1.528.2.10.