kernel/module.c: Mark module state before set RO and NX regions

In some architectures like arm/arm64, set_memory_*() check module address and state as well. Mark module state before set RO and NX regions for the routine is passed.

It will fix wrong RO/NX protection for loadable kernel modules on arm/arm64.

Signed-off-by Jungseung Lee <[email protected]>

---
 kernel/module.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

kernel/module.c +4 -3

index 3965511..7e7cc9f 100644
@@ -3152,6 +3152,10 @@ static int complete_formation(struct module *mod, struct load_info *info)
 	/* This relies on module_mutex for list integrity. */
 	module_bug_finalize(info->hdr, info->sechdrs, mod);
 
+	/* Mark state as coming so strong_try_module_get() ignores us,
+	 * but kallsyms etc. can see us. */
+	mod->state = MODULE_STATE_COMING;
+
 	/* Set RO and NX regions for core */
 	set_section_ro_nx(mod->module_core,
 				mod->core_text_size,

@@ -3164,9 +3168,6 @@ static int complete_formation(struct module *mod, struct load_info *info)
 				mod->init_ro_size,
 				mod->init_size);
 
-	/* Mark state as coming so strong_try_module_get() ignores us,
-	 * but kallsyms etc. can see us. */
-	mod->state = MODULE_STATE_COMING;
 	mutex_unlock(&module_mutex);
 
 	blocking_notifier_call_chain(&module_notify_list,

Signature · 1 line

1.9.1

Quoted 5 lines · Jungseung Lee

In some architectures like arm/arm64, set_memory_*() check module address and state as well. Mark module state before set RO and NX regions for the routine is passed.

It will fix wrong RO/NX protection for loadable kernel modules on arm/arm64.

This partially reverts commit 4982223e51e8ea9d09bb33c8323b5ec1877b2b51

Author: Rusty Russell <[email protected]>
Date:   Wed May 14 10:54:19 2014 +0930

module: set nx before marking module MODULE_STATE_COMING.

Laura Abbott (CC'd) was looking at an alternative fix for this. Laura?

Thanks,
Rusty.

Quoted 19 lines

Quoted 7 lines · Jungseung Lee

In some architectures like arm/arm64, set_memory_*() check module address and state as well. Mark module state before set RO and NX regions for the routine is passed.

It will fix wrong RO/NX protection for loadable kernel modules on arm/arm64.

This partially reverts commit 4982223e51e8ea9d09bb33c8323b5ec1877b2b51

Author: Rusty Russell <[email protected]>
Date:   Wed May 14 10:54:19 2014 +0930

module: set nx before marking module MODULE_STATE_COMING.

Laura Abbott (CC'd) was looking at an alternative fix for this. Laura?

Quoted 3 lines

Thanks,
Rusty.

Yes, my proposal was to stop using is_module_address and just bounds check against the module ranges[1]. I got bogged down with other tasks and hadn't submitted a patch for review yet.

Thanks,
Laura

[1]
http://lists.infradead.org/pipermail/linux-arm-kernel/2014-December/311574.html

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