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@@ -0,0 +1,59 @@
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+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
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+From: Jay Vosburgh <[email protected]>
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+Date: Wed, 24 Jan 2018 21:43:56 -0800
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+Subject: [PATCH] UBUNTU: SAUCE: x86/entry: Fix up retpoline assembler labels
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+MIME-Version: 1.0
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+Content-Type: text/plain; charset=UTF-8
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+Content-Transfer-Encoding: 8bit
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+
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+The extant assembler labels in entry_SYSCALL_64_fastpath
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+result in the error path incorrectly entering the retpoline logic.
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+This results in that logic jumping to whatever address is in %r10,
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+which is the fourth system call argument.
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+
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+This enables a trivial means to instruct the kernel to jump
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+to any arbitrary address. Non-malicious executables making invalid
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+system calls may also cause the system to crash.
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+
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+Resolve this by renumbering the assembler labels as is found
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+in other kernels.
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+
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+CVE-2017-5753
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+CVE-2017-5715
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+
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+Fixes: d2e0236 ("x86/entry: Use retpoline for syscall's indirect calls")
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+Signed-off-by: Jay Vosburgh <[email protected]>
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+Signed-off-by: Stefan Bader <[email protected]>
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+(cherry picked from commit 57ed6ed2b6284c10b8d2e0072c680d0e6adac2dc)
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+Signed-off-by: Fabian Grünbichler <[email protected]>
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+---
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+ arch/x86/entry/entry_64.S | 12 ++++++------
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+ 1 file changed, 6 insertions(+), 6 deletions(-)
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+
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+diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
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+index be7196967f9f..5a6e41499e67 100644
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+--- a/arch/x86/entry/entry_64.S
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++++ b/arch/x86/entry/entry_64.S
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+@@ -277,13 +277,13 @@ entry_SYSCALL_64_fastpath:
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+ * and all argument registers are clobbered.
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+ */
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+ movq sys_call_table(, %rax, 8), %r10
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+- jmp 1f
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+-4: callq 2f
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+-3: nop
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+- jmp 3b
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+-2: mov %r10, (%rsp)
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++ jmp 1001f
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++1004: callq 1002f
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++1003: nop
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++ jmp 1003b
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++1002: mov %r10, (%rsp)
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+ retq
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+-1: callq 4b
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++1001: callq 1004b
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+
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+ .Lentry_SYSCALL_64_after_fastpath_call:
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+
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+--
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+2.14.2
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+
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Fabian Grünbichler