[PATCH bpf-next v4 0/2] Fix bpf_strnstr len error

From: Rong Tao
Date: Thu Aug 28 2025 - 22:12:54 EST


From: Rong Tao <rongtao@xxxxxxxx>

Fix bpf_strnstr() wrong 'len' parameter, bpf_strnstr("open", "open", 4)
should return 0 instead of -ENOENT.

Rong Tao (2):
bpf/helpers: bpf_strnstr: Exact match length
selftests/bpf: Add tests for bpf_strnstr

kernel/bpf/helpers.c | 10 +++++++++-
.../selftests/bpf/progs/string_kfuncs_success.c | 8 ++++++--
2 files changed, 15 insertions(+), 3 deletions(-)

---
v4: Add comment and more selftests;
v3: Fix selftests/bpf error in v2, sorry about that;
https://lore.kernel.org/lkml/tencent_69BD268FBA201219240B51661D5E96A8D80A@xxxxxx/
v2: Follow Andrii Nakryiko's advise, fix the 'wrong fix';
https://lore.kernel.org/lkml/tencent_DF4DA83EEBFB9246E5E3357BB40911CCA005@xxxxxx/
v1: https://lore.kernel.org/lkml/tencent_65E5988AD52BEC280D22964189505CD6ED06@xxxxxx/
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2.51.0