libbpf-tools/trace_helpers.c: free() called more than once#5514
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isabert wants to merge 2 commits into
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libbpf-tools/trace_helpers.c: free() called more than once#5514isabert wants to merge 2 commits into
isabert wants to merge 2 commits into
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dso__free_fields could be called by (err_out in trace_helpers.c) and then by the finalizer (cleanup in profile.c). This will cause the case where a dangling pointer is freed. To fix this issue - the freed pointers are set to NULL. Furthermore, to prevent lazy reload `if (!dso->syms && dso__load_sym_table(dso))` from populating dso again, size and capacity are also set to 0
isabert
requested review from
brendangregg,
chenhengqi,
ekyooo and
yonghong-song
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Pull request overview
Fixes a double-free/dangling-pointer scenario in libbpf-tools symbol handling by clearing freed struct dso fields so repeated cleanup paths don’t re-free the same memory.
Changes:
- After freeing
dso-owned allocations, sets the freed pointers toNULL. - Resets
syms_sz/syms_capto avoid stale symbol-table sizing state after cleanup.
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
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dso__free_fields could be called by (err_out in trace_helpers.c) and then by the finalizer (cleanup in profile.c).
This will cause the case where a dangling pointer is freed. To fix this issue - the freed pointers are set to NULL.
Furthermore, to prevent lazy reload
if (!dso->syms && dso__load_sym_table(dso))from populating dso again, size and capacity are also set to 0Checklist
tools/toolname:,libbpf-tools/toolname:,src/cc:,docs:,build:,tests/python:)