From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Tue, 3 Apr 2018 10:29:28 +0000 (+0200)
Subject: 4.4-stable patches
X-Git-Tag: v3.18.103~51
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ee5f33c58d484f2c854583ab697c46bd67ea18f2;p=thirdparty%2Fkernel%2Fstable-queue.git

4.4-stable patches

added patches:
	kprobes-x86-fix-to-set-rwx-bits-correctly-before-releasing-trampoline.patch
---

diff --git a/queue-4.4/kprobes-x86-fix-to-set-rwx-bits-correctly-before-releasing-trampoline.patch b/queue-4.4/kprobes-x86-fix-to-set-rwx-bits-correctly-before-releasing-trampoline.patch
new file mode 100644
index 00000000000..268fbe381a8
--- /dev/null
+++ b/queue-4.4/kprobes-x86-fix-to-set-rwx-bits-correctly-before-releasing-trampoline.patch
@@ -0,0 +1,66 @@
+From c93f5cf571e7795f97d49ef51b766cf25e328545 Mon Sep 17 00:00:00 2001
+From: Masami Hiramatsu <mhiramat@kernel.org>
+Date: Thu, 25 May 2017 19:38:17 +0900
+Subject: kprobes/x86: Fix to set RWX bits correctly before releasing trampoline
+
+From: Masami Hiramatsu <mhiramat@kernel.org>
+
+commit c93f5cf571e7795f97d49ef51b766cf25e328545 upstream.
+
+Fix kprobes to set(recover) RWX bits correctly on trampoline
+buffer before releasing it. Releasing readonly page to
+module_memfree() crash the kernel.
+
+Without this fix, if kprobes user register a bunch of kprobes
+in function body (since kprobes on function entry usually
+use ftrace) and unregister it, kernel hits a BUG and crash.
+
+Link: http://lkml.kernel.org/r/149570868652.3518.14120169373590420503.stgit@devbox
+
+Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
+Fixes: d0381c81c2f7 ("kprobes/x86: Set kprobes pages read-only")
+Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
+Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/x86/kernel/kprobes/core.c |    9 +++++++++
+ kernel/kprobes.c               |    2 +-
+ 2 files changed, 10 insertions(+), 1 deletion(-)
+
+--- a/arch/x86/kernel/kprobes/core.c
++++ b/arch/x86/kernel/kprobes/core.c
+@@ -49,6 +49,7 @@
+ #include <linux/kdebug.h>
+ #include <linux/kallsyms.h>
+ #include <linux/ftrace.h>
++#include <linux/moduleloader.h>
+ 
+ #include <asm/cacheflush.h>
+ #include <asm/desc.h>
+@@ -402,6 +403,14 @@ int __copy_instruction(u8 *dest, u8 *src
+ 	return length;
+ }
+ 
++/* Recover page to RW mode before releasing it */
++void free_insn_page(void *page)
++{
++	set_memory_nx((unsigned long)page & PAGE_MASK, 1);
++	set_memory_rw((unsigned long)page & PAGE_MASK, 1);
++	module_memfree(page);
++}
++
+ static int arch_copy_kprobe(struct kprobe *p)
+ {
+ 	int ret;
+--- a/kernel/kprobes.c
++++ b/kernel/kprobes.c
+@@ -125,7 +125,7 @@ static void *alloc_insn_page(void)
+ 	return module_alloc(PAGE_SIZE);
+ }
+ 
+-static void free_insn_page(void *page)
++void __weak free_insn_page(void *page)
+ {
+ 	module_memfree(page);
+ }
diff --git a/queue-4.4/series b/queue-4.4/series
index a3136b169e7..b17dc33d270 100644
--- a/queue-4.4/series
+++ b/queue-4.4/series
@@ -8,3 +8,4 @@ usb-gadget-change-len-to-size_t-on-alloc_ep_req.patch
 usb-gadget-fix-usb_ep_align_maybe-endianness-and-new-usb_ep_align.patch
 usb-gadget-align-buffer-size-when-allocating-for-out-endpoint.patch
 usb-gadget-f_hid-fix-prevent-accessing-released-memory.patch
+kprobes-x86-fix-to-set-rwx-bits-correctly-before-releasing-trampoline.patch