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>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index ca7396e..4c4df05 100644 (file)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1100,7 +1100,7 @@ void trace_find_cmdline(int pid, char comm[])
        arch_spin_lock(&trace_cmdline_lock);
        map = map_pid_to_cmdline[pid];
        if (map != NO_CMDLINE_MAP)
        arch_spin_lock(&trace_cmdline_lock);
        map = map_pid_to_cmdline[pid];
        if (map != NO_CMDLINE_MAP)

-               strcpy(comm, saved_cmdlines[map]);
+               strlcpy(comm, saved_cmdlines[map], TASK_COMM_LEN);

        else
                strcpy(comm, "<...>");
 
        else
                strcpy(comm, "<...>");