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Date: Tue, 24 Apr 2007 15:59:45 +1000
From: Paul Mackerras <paulus@samba.org>
To: Srinivasa Ds <srinivasa@in.ibm.com>
Cc: linux-kernel@vger.kernel.org, ananth@in.ibm.com,
       Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] Transparently handle <.symbol> lookup for kprobes
In-Reply-To: <200704231128.49041.srinivasa@in.ibm.com>
References: <200704231128.49041.srinivasa@in.ibm.com>
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Srinivasa Ds writes:

> +	} else {							\
> +		char dot_name[KSYM_NAME_LEN+1];				\
> +		dot_name[0] = '.';					\
> +		dot_name[1] = '\0';					\
> +		strncat(dot_name, name, KSYM_NAME_LEN);			\

Assuming the kernel strncat works like the userspace one does, there
is a possibility that dot_name[] won't be properly null-terminated
here.  If strlen(name) >= KSYM_NAME_LEN-1, then strncat will set
dot_name[KSYM_NAME_LEN-1] to something non-null and won't touch
dot_name[KSYM_NAME_LEN].

Paul.