diff mbox series

[v4,mips-next,4/7] MIPS: vmlinux.lds.S: catch bad .rel.dyn at link time

Message ID 20210107132010.463129-1-alobakin@pm.me (mailing list archive)
State Superseded
Headers show
Series MIPS: vmlinux.lds.S sections fixes & cleanup | expand

Commit Message

Alexander Lobakin Jan. 7, 2021, 1:20 p.m. UTC 
Catch any symbols placed in .rel.dyn and check for these sections
to be zero-sized at link time.
Eliminates following ld warning:

mips-alpine-linux-musl-ld: warning: orphan section `.rel.dyn'
from `init/main.o' being placed in section `.rel.dyn'

Adopted from x86/kernel/vmlinux.lds.S.

Suggested-by: Fangrui Song <maskray@google.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
---
 arch/mips/kernel/vmlinux.lds.S | 11 +++++++++++
 1 file changed, 11 insertions(+)

Comments

Kees Cook Jan. 7, 2021, 9:48 p.m. UTC | #1 
On Thu, Jan 07, 2021 at 01:20:33PM +0000, Alexander Lobakin wrote:
> Catch any symbols placed in .rel.dyn and check for these sections
> to be zero-sized at link time.
> Eliminates following ld warning:
> 
> mips-alpine-linux-musl-ld: warning: orphan section `.rel.dyn'
> from `init/main.o' being placed in section `.rel.dyn'
> 
> Adopted from x86/kernel/vmlinux.lds.S.
> 
> Suggested-by: Fangrui Song <maskray@google.com>
> Signed-off-by: Alexander Lobakin <alobakin@pm.me>

Reviewed-by: Kees Cook <keescook@chromium.org>
Nathan Chancellor Jan. 8, 2021, 9:17 p.m. UTC | #2 
On Thu, Jan 07, 2021 at 01:20:33PM +0000, Alexander Lobakin wrote:
> Catch any symbols placed in .rel.dyn and check for these sections
> to be zero-sized at link time.
> Eliminates following ld warning:
> 
> mips-alpine-linux-musl-ld: warning: orphan section `.rel.dyn'
> from `init/main.o' being placed in section `.rel.dyn'
> 
> Adopted from x86/kernel/vmlinux.lds.S.
> 
> Suggested-by: Fangrui Song <maskray@google.com>
> Signed-off-by: Alexander Lobakin <alobakin@pm.me>

Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>

> ---
>  arch/mips/kernel/vmlinux.lds.S | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
> index 0f4e46ea4458..0f736d60d43e 100644
> --- a/arch/mips/kernel/vmlinux.lds.S
> +++ b/arch/mips/kernel/vmlinux.lds.S
> @@ -226,4 +226,15 @@ SECTIONS
>  		*(.pdr)
>  		*(.reginfo)
>  	}
> +
> +	/*
> +	 * Sections that should stay zero sized, which is safer to
> +	 * explicitly check instead of blindly discarding.
> +	 */
> +
> +	.rel.dyn : {
> +		*(.rel.*)
> +		*(.rel_*)
> +	}
> +	ASSERT(SIZEOF(.rel.dyn) == 0, "Unexpected run-time relocations (.rel) detected!")
>  }
> -- 
> 2.30.0
> 
>
diff mbox series

Patch

diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
index 0f4e46ea4458..0f736d60d43e 100644
--- a/arch/mips/kernel/vmlinux.lds.S
+++ b/arch/mips/kernel/vmlinux.lds.S
@@ -226,4 +226,15 @@  SECTIONS
 		*(.pdr)
 		*(.reginfo)
 	}
+
+	/*
+	 * Sections that should stay zero sized, which is safer to
+	 * explicitly check instead of blindly discarding.
+	 */
+
+	.rel.dyn : {
+		*(.rel.*)
+		*(.rel_*)
+	}
+	ASSERT(SIZEOF(.rel.dyn) == 0, "Unexpected run-time relocations (.rel) detected!")
 }