vmlinux.lds.h: Fix placement of '.data..decrypted' section

commit 000f8870a47bdc36730357883b6aef42bced91ee upstream.

Commit d4c639990036 ("vmlinux.lds.h: Avoid orphan section with !SMP")
fixed an orphan section warning by adding the '.data..decrypted' section
to the linker script under the PERCPU_DECRYPTED_SECTION define but that
placement introduced a panic with !SMP, as the percpu sections are not
instantiated with that configuration so attempting to access variables
defined with DEFINE_PER_CPU_DECRYPTED() will result in a page fault.

Move the '.data..decrypted' section to the DATA_MAIN define so that the
variables in it are properly instantiated at boot time with
CONFIG_SMP=n.

Cc: stable@vger.kernel.org
Fixes: d4c639990036 ("vmlinux.lds.h: Avoid orphan section with !SMP")
Link: https://lore.kernel.org/cbbd3548-880c-d2ca-1b67-5bb93b291d5f@huawei.com/
Debugged-by: Ard Biesheuvel <ardb@kernel.org>
Reported-by: Zhao Wenhui <zhaowenhui8@huawei.com>
Tested-by: xiafukun <xiafukun@huawei.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221108174934.3384275-1-nathan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 9eac202..e28792c 100644 (file)
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -337,6 +337,7 @@
 #define DATA_DATA                                                      \
        *(.xiptext)                                                     \
        *(DATA_MAIN)                                                    \
+       *(.data..decrypted)                                             \
        *(.ref.data)                                                    \
        *(.data..shared_aligned) /* percpu related */                   \
        MEM_KEEP(init.data*)                                            \
@@ -969,7 +970,6 @@
 #ifdef CONFIG_AMD_MEM_ENCRYPT
 #define PERCPU_DECRYPTED_SECTION                                       \
        . = ALIGN(PAGE_SIZE);                                           \
-       *(.data..decrypted)                                             \
        *(.data..percpu..decrypted)                                     \
        . = ALIGN(PAGE_SIZE);
 #else