From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Mon, 2 Mar 2020 15:40:26 +0000 (-0500)
Subject: Remove work-around for signed tracepoint module tainting (kernel 3.15+)
X-Git-Tag: v2.12.0-rc3~7
X-Git-Url: http://git.lttng.org./?a=commitdiff_plain;h=9cd95afe04c5d8a055f3ecafdb3bea7d4360f92d;p=lttng-modules.git

Remove work-around for signed tracepoint module tainting (kernel 3.15+)

Upstream commit 66cc69e34e86a "Fix: module signature vs tracepoints: add
new TAINT_UNSIGNED_MODULE" fixed an issue where the kernel was
considering unsigned modules as tainting the kernel in the same way as a
force-loaded modules, which was causing the tracepoints within those
modules to be hidden.

This fix was merged in kernel 3.15, so there is no use in applying this
work-around starting from that kernel.

This removes a dependency on kallsyms_lookup_name() for the symbol
"tracepoint_module_notify".

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/wrapper/tracepoint.h b/wrapper/tracepoint.h
index 6ee42177..08e8ccab 100644
--- a/wrapper/tracepoint.h
+++ b/wrapper/tracepoint.h
@@ -46,7 +46,7 @@ void lttng_tracepoint_exit(void)
 
 #endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,15,0)) */
 
-#ifdef CONFIG_MODULE_SIG
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(3,15,0) && defined(CONFIG_MODULE_SIG))
 
 #include <linux/kallsyms.h>
 #include <wrapper/kallsyms.h>
@@ -68,9 +68,9 @@ int wrapper_tracepoint_module_notify(struct notifier_block *nb,
 	}
 }
 
-#endif /* CONFIG_MODULE_SIG */
+#endif /* #if (LINUX_VERSION_CODE < KERNEL_VERSION(3,15,0) && defined(CONFIG_MODULE_SIG)) */
 
-#if defined(CONFIG_MODULE_SIG) && defined(MODULE)
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(3,15,0) && defined(CONFIG_MODULE_SIG) && defined(MODULE))
 
 static inline
 int wrapper_lttng_fixup_sig(struct module *mod)
@@ -91,7 +91,7 @@ int wrapper_lttng_fixup_sig(struct module *mod)
 	return ret;
 }
 
-#else /* #if defined(CONFIG_MODULE_SIG) && defined(MODULE) */
+#else /* #if (LINUX_VERSION_CODE < KERNEL_VERSION(3,15,0) && defined(CONFIG_MODULE_SIG) && defined(MODULE)) */
 
 static inline
 int wrapper_lttng_fixup_sig(struct module *mod)
@@ -99,7 +99,7 @@ int wrapper_lttng_fixup_sig(struct module *mod)
 	return 0;
 }
 
-#endif /*#else #if defined(CONFIG_MODULE_SIG) && defined(MODULE) */
+#endif /* #else #if (LINUX_VERSION_CODE < KERNEL_VERSION(3,15,0) && defined(CONFIG_MODULE_SIG) && defined(MODULE)) */
 
 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,19,0))
 static inline struct tracepoint *lttng_tracepoint_ptr_deref(tracepoint_ptr_t *p)