[PATCH] tracing: Use strlcpy() instead of strcpy() in __trace_find_cmdline() (Was: Re: [PATCH] tracing: Resolve stack corruption due to string copy)

From: Steven Rostedt
Date: Wed May 03 2017 - 10:09:41 EST

[ Here's the new patch ]

From: Amey Telawane <ameyt@xxxxxxxxxxxxxx>

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@xxxxxxxxxx

Signed-off-by: Amey Telawane <ameyt@xxxxxxxxxxxxxx>
[AmitP: Cherry-picked this commit from CodeAurora kernel/msm-3.10
Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
[ Updated change log and removed the "- 1" from len parameter ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
kernel/trace/trace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5b645b0..c1b0f53 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1976,7 +1976,7 @@ static void __trace_find_cmdline(int pid, char comm[])

map = savedcmd->map_pid_to_cmdline[pid];
if (map != NO_CMDLINE_MAP)
- strcpy(comm, get_saved_cmdlines(map));
+ strlcpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN);
strcpy(comm, "<...>");