Fixes double-free error in linker.c:bpf_linker__free() caused by realloc(..., 0) call in linker.c:extend_sec() (such a call "frees" memory every second time :). The error is triggered when object files with empty sections of the same name are processed by linker. - The first patch extends progs/linked_funcs[12].c to trigger the error upon tests compilation; - The second patch contains detailed description of the error, fix and appropriate attributions. Eduard Zingerman (2): selftests/bpf: Test if bpftool linker handles empty sections libbpf: Fix double-free when linker processes empty sections tools/lib/bpf/linker.c | 14 +++++++++++++- tools/testing/selftests/bpf/progs/linked_funcs1.c | 3 +++ tools/testing/selftests/bpf/progs/linked_funcs2.c | 3 +++ 3 files changed, 19 insertions(+), 1 deletion(-) -- 2.40.0
