On Mon, 12 Jun 2017 17:25:52 +0200 Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > 4.11-stable review patch. If anyone has any objections, please let me know. > > ------------------ > > From: Amey Telawane <ameyt@xxxxxxxxxxxxxx> > > 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@xxxxxxxxxx > > Signed-off-by: Amey Telawane <ameyt@xxxxxxxxxxxxxx> > [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@xxxxxxxxxx> > [ Updated change log and removed the "- 1" from len parameter ] > Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> FYI, I never marked this for stable because there's nothing broken that it fixes. It's more of a "just in case". The "comm" passed in is allocated to be TASK_COMM_LEN, and is updated at creation using strlcpy() with TASK_COMM_LEN. It's the task->comm. It's used throughout the kernel. If it were ever to be bigger than TASK_COMM_LEN or not end with a '\0' there would be many other bugs, as task->comm is used throughout the kernel with assumptions that these two cases are always true. I accepted the patch because it doesn't hurt. I'm fine if it goes to stable, but I find it rather redundant. -- Steve > > --- > kernel/trace/trace.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -1899,7 +1899,7 @@ static void __trace_find_cmdline(int pid > > 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); > else > strcpy(comm, "<...>"); > } >