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Date: Tue, 19 Mar 2013 15:32:35 -0400
From: William Haddon <william@...donthethird.net>
To: musl@...ts.openwall.com
Subject: Weird bug in syslog


Hi all.

I noticed seg-faults and other weird behavior when using the syslog() 
function with large messages. I've attached the simplest test program 
that reproduces the problem. I've observed it to break on 0.9.9 on i386 
and current git on x86_64. The problem seems to be that although the 
syslog function successfully truncates its input to 256 bytes, it 
passes the size of the un-truncated form to the sendto() call because 
snprintf returns the number of bytes that would be written if 
truncation did not occur. Fixing syslog to check if truncation occurred 
seems to fix the problem. I've attached the patch that does this.

William Haddon

View attachment "test3.c" of type "text/x-csrc" (338 bytes)

View attachment "musl-syslog.patch" of type "text/x-patch" (533 bytes)

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