From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Joel Fernandes (Google)" Subject: [PATCH v3 3/3] module: Make __tracepoints_ptrs as read-only Date: Wed, 10 Apr 2019 15:57:08 -0400 Message-Id: <20190410195708.162185-3-joel@joelfernandes.org> In-Reply-To: <20190410195708.162185-1-joel@joelfernandes.org> References: <20190410195708.162185-1-joel@joelfernandes.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , paulmck@linux.vnet.ibm.com, keescook@chromium.org, mathieu.desnoyers@efficios.com, rostedt@goodmis.org, Jessica Yu , kernel-hardening@lists.openwall.com, kernel-team@android.com, rcu@vger.kernel.org List-ID: This series hardens the tracepoints in modules by making the array of pointers referring to the tracepoints as read-only. This array is needed during module unloading to verify that the tracepoint is quiescent. There is no reason for the array to be to be writable after init, and can cause security or other hidden bugs. Mark these as ro_after_init. Suggested-by: paulmck@linux.vnet.ibm.com Suggested-by: keescook@chromium.org Suggested-by: mathieu.desnoyers@efficios.com Cc: rostedt@goodmis.org Signed-off-by: Joel Fernandes (Google) --- kernel/module.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/module.c b/kernel/module.c index 8b9631e789f0..be980aaa8804 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3320,6 +3320,12 @@ static const char * const ro_after_init_sections[] = { * by the SRCU notifiers */ "___srcu_struct_ptrs", + + /* + * Array of tracepoint pointers used for checking if tracepoints are + * quiescent during unloading. + */ + "__tracepoints_ptrs", }; static struct module *layout_and_allocate(struct load_info *info, int flags) -- 2.21.0.392.gf8f6787159e-goog