tracing: Use strlcpy() instead of strcpy() in __trace_find_cmdline()

tracing: Use strlcpy() instead of strcpy() in __trace_find_cmdline()

commit e09e28671cda63e6308b31798b997639120e2a21 upstream.

Strcpy is inherently not safe, and strlcpy() should be used instead.
__trace_find_cmdline() uses strcpy() because the comms saved must have a
terminating nul character, but it doesn't hurt to add the extra protection
of using strlcpy() instead of strcpy().

Link: http://lkml.kernel.org/r/1493806274-13936-1-git-send-email-amit.pundir@linaro.org
Signed-off-by: Amey Telawane <ameyt@codeaurora.org>
[AmitP: Cherry-picked this commit from CodeAurora kernel/msm-3.10
https://source.codeaurora.org/quic/la/kernel/msm-3.10/commit/?id=2161ae9a70b12cf18ac8e5952a20161ffbccb477]
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
[ Updated change log and removed the "- 1" from len parameter ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
[sw0312.kim: backport from mainline to fix CVE-2017-0605 even though it is rejected
 - change function to trace_find_cmdline() ]
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Change-Id: Ifb711efeec1951b09e6888b2ea3d0cdf7310903e