Re: [PATCH 5/5] selinux: drop unnecessary NULL check

From: Nick Desaulniers
Date: Tue Jun 07 2022 - 20:42:54 EST


On Tue, Jun 7, 2022 at 2:22 PM Paul Moore <paul@xxxxxxxxxxxxxx> wrote:
>
> On Thu, Feb 17, 2022 at 9:22 AM Christian Göttsche
> <cgzones@xxxxxxxxxxxxxx> wrote:
> >
> > Commit e3489f8974e1 ("selinux: kill selinux_sb_get_mnt_opts()")
> > introduced a NULL check on the context after a successful call to
> > security_sid_to_context(). This is on the one hand redundant after
> > checking for success and on the other hand insufficient on an actual
> > NULL pointer, since the context is passed to seq_escape() leading to a
> > call of strlen() on it.
> >
> > Reported by Clang analyzer:
> >
> > In file included from security/selinux/hooks.c:28:
> > In file included from ./include/linux/tracehook.h:50:
> > In file included from ./include/linux/memcontrol.h:13:
> > In file included from ./include/linux/cgroup.h:18:
> > ./include/linux/seq_file.h:136:25: warning: Null pointer passed as 1st argument to string length function [unix.cstring.NullArg]
> > seq_escape_mem(m, src, strlen(src), flags, esc);
> > ^~~~~~~~~~~
> >
> > Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
> > ---
> > security/selinux/hooks.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
>
> I was waiting for Nick to reply, but he never did, and this looks good
> to me so I just merged it into selinux/next. Thanks for your patience
> Christian.

LGTM; you can ping me on irc #ndesaulniers on most kernel channels if
you're waiting on me. ;)

>
> --
> paul-moore.com



--
Thanks,
~Nick Desaulniers