linux-kernel - [PATCH] rust: build: remap path to avoid absolute path

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260207144356.3063613-1-gary@kernel.org>
Date: Sat,  7 Feb 2026 14:43:55 +0000
From: Gary Guo <gary@...nel.org>
To: Miguel Ojeda <ojeda@...nel.org>,
	Boqun Feng <boqun@...nel.org>,
	Gary Guo <gary@...yguo.net>,
	Björn Roy Baron <bjorn3_gh@...tonmail.com>,
	Benno Lossin <lossin@...nel.org>,
	Andreas Hindborg <a.hindborg@...nel.org>,
	Alice Ryhl <aliceryhl@...gle.com>,
	Trevor Gross <tmgross@...ch.edu>,
	Danilo Krummrich <dakr@...nel.org>,
	Nathan Chancellor <nathan@...nel.org>,
	Nicolas Schier <nsc@...nel.org>
Cc: Janne Grunau <j@...nau.net>,
	Asahi Lina <lina+kernel@...hilina.net>,
	rust-for-linux@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-kbuild@...r.kernel.org
Subject: [PATCH] rust: build: remap path to avoid absolute path

From: Gary Guo <gary@...yguo.net>

When building with a out directory (O=), absolute paths can end up in the
file name in `#[track_caller]` or the panic message. This is not desirable
as this leaks the exact path being used to build the kernel into the binary
which is not very helpful to achieve reproducibility. It also means that
the same location can appear in two forms (relative or absolute).

This is reported by Asahi [1] and is being workaround in [2] previously to
force everything to be absolute path. Using absolute path for everything
sovles the inconsistency, however it does not address the reproducibility
issue. So, fix this by remap all absolute paths to srctree to relative path
instead.

This change can be validated by building a kernel with O=, strip debug info
on vmlinux, and then check if the absolute path exists in `strings vmlinux`,
e.g. `strings vmlinux |grep \/home`.

Reported-by: Janne Grunau <j@...nau.net>
Reported-by: Asahi Lina <lina+kernel@...hilina.net>
Closes: https://rust-for-linux.zulipchat.com/#narrow/channel/288089-General/topic/Per-call-site.20data.20and.20lock.20class.20keys/near/572466559 [1]
Link: https://github.com/AsahiLinux/linux/commit/54ab88878869036c9d6620101bfe17a81e88c2f9 [2]
Signed-off-by: Gary Guo <gary@...yguo.net>
---
 rust/Makefile          | 1 +
 scripts/Makefile.build | 1 +
 2 files changed, 2 insertions(+)

diff --git a/rust/Makefile b/rust/Makefile
index 629b3bdd2b20..598d2efede32 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -582,6 +582,7 @@ quiet_cmd_rustc_library = $(if $(skip_clippy),RUSTC,$(RUSTC_OR_CLIPPY_QUIET)) L
 		--crate-type rlib -L$(objtree)/$(obj) \
 		--crate-name $(patsubst %.o,%,$(notdir $@)) $< \
 		--sysroot=/dev/null \
+		--remap-path-prefix=$(abspath $(srctree))= \
 		-Zunstable-options \
 	$(if $(rustc_objcopy),;$(OBJCOPY) $(rustc_objcopy) $@) \
 	$(cmd_objtool)
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 204e58dd1bb0..03dde30e953c 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -333,6 +333,7 @@ rust_common_cmd = \
 	--crate-type rlib -L $(objtree)/rust/ \
 	--crate-name $(basename $(notdir $@)) \
 	--sysroot=/dev/null \
+	--remap-path-prefix=$(abspath $(srctree))= \
 	--out-dir $(dir $@) --emit=dep-info=$(depfile)
 
 # `--emit=obj`, `--emit=asm` and `--emit=llvm-ir` imply a single codegen unit

base-commit: 36896083ef4dbc302e406f01975a227784160cf8
-- 
2.51.2