When dynamically linking, Address Sanitizer requires its library to be the first one to be loaded; this is apparently to ensure that every call to malloc is intercepted. If using LD_PRELOAD, those listed libraries will be loaded before the libraries listed in the program's ELF and will therefore violate this requirement, leading to the below failure and output from ASan.

commit 58e2847ad2e6 ("selftests: line buffer test program's stdout") modified the kselftest runner to force line buffering by forcing the test programs to run through `stdbuf`. It turns out that stdbuf implements line buffering by injecting a library via LD_PRELOAD. Therefore selftests that use ASan started failing.

Fix this by statically linking libasan in the affected test programs, using the `-static-libasan` option. Note this is already the default for Clang, but not got GCC.

Test output sample for failing case:

TAP version 13 1..3 # timeout set to 300 # selftests: openat2: openat2_test # ==4052==ASan runtime does not come first in initial library list; you should either link runtime to your application or manually preload it with LD_PRELOAD. not ok 1 selftests: openat2: openat2_test # exit=1 # timeout set to 300 # selftests: openat2: resolve_test # ==4070==ASan runtime does not come first in initial library list; you should either link runtime to your application or manually preload it with LD_PRELOAD. not ok 2 selftests: openat2: resolve_test # exit=1

Signed-off-by: Ryan Roberts ryan.roberts@arm.com Fixes: 58e2847ad2e6 ("selftests: line buffer test program's stdout") Reported-by: kernel test robot oliver.sang@intel.com Closes: https://lore.kernel.org/oe-lkp/202309121342.97e2f008-oliver.sang@intel.com --- tools/testing/selftests/fchmodat2/Makefile | 2 +- tools/testing/selftests/openat2/Makefile | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/fchmodat2/Makefile b/tools/testing/selftests/fchmodat2/Makefile index 20839f8e43f2..71ec34bf1501 100644 --- a/tools/testing/selftests/fchmodat2/Makefile +++ b/tools/testing/selftests/fchmodat2/Makefile @@ -1,6 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-or-later

-CFLAGS += -Wall -O2 -g -fsanitize=address -fsanitize=undefined $(KHDR_INCLUDES) +CFLAGS += -Wall -O2 -g -fsanitize=address -fsanitize=undefined -static-libasan $(KHDR_INCLUDES) TEST_GEN_PROGS := fchmodat2_test

include ../lib.mk diff --git a/tools/testing/selftests/openat2/Makefile b/tools/testing/selftests/openat2/Makefile index 843ba56d8e49..254d676a2689 100644 --- a/tools/testing/selftests/openat2/Makefile +++ b/tools/testing/selftests/openat2/Makefile @@ -1,6 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-or-later

-CFLAGS += -Wall -O2 -g -fsanitize=address -fsanitize=undefined +CFLAGS += -Wall -O2 -g -fsanitize=address -fsanitize=undefined -static-libasan TEST_GEN_PROGS := openat2_test resolve_test rename_attack_test

include ../lib.mk -- 2.25.1