From: Alan Maguire <alan.maguire@oracle.com> mainline inclusion from mainline-v6.11-rc1 commit d1cf840854bb603c0718a011bc993f69f2df014e category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8335 CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... ---------------------------------------------------------------------- Use less verbose names in BTF relocation code and fix off-by-one error and typo in btf_relocate.c. Simplify loop over matching distilled types, moving from assigning a _next value in loop body to moving match check conditions into the guard. Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com> Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20240620091733.1967885-2-alan.maguire@oracle.com Signed-off-by: Luo Gengkun <luogengkun2@huawei.com> --- tools/lib/bpf/btf_relocate.c | 72 ++++++++++++++++-------------------- 1 file changed, 31 insertions(+), 41 deletions(-) diff --git a/tools/lib/bpf/btf_relocate.c b/tools/lib/bpf/btf_relocate.c index eabb8755f662..23a41fb03e0d 100644 --- a/tools/lib/bpf/btf_relocate.c +++ b/tools/lib/bpf/btf_relocate.c @@ -160,7 +160,7 @@ static int btf_mark_embedded_composite_type_ids(struct btf_relocate *r, __u32 i) */ static int btf_relocate_map_distilled_base(struct btf_relocate *r) { - struct btf_name_info *dist_base_info_sorted, *dist_base_info_sorted_end; + struct btf_name_info *info, *info_end; struct btf_type *base_t, *dist_t; __u8 *base_name_cnt = NULL; int err = 0; @@ -169,26 +169,24 @@ static int btf_relocate_map_distilled_base(struct btf_relocate *r) /* generate a sort index array of name/type ids sorted by name for * distilled base BTF to speed name-based lookups. */ - dist_base_info_sorted = calloc(r->nr_dist_base_types, sizeof(*dist_base_info_sorted)); - if (!dist_base_info_sorted) { + info = calloc(r->nr_dist_base_types, sizeof(*info)); + if (!info) { err = -ENOMEM; goto done; } - dist_base_info_sorted_end = dist_base_info_sorted + r->nr_dist_base_types; + info_end = info + r->nr_dist_base_types; for (id = 0; id < r->nr_dist_base_types; id++) { dist_t = btf_type_by_id(r->dist_base_btf, id); - dist_base_info_sorted[id].name = btf__name_by_offset(r->dist_base_btf, - dist_t->name_off); - dist_base_info_sorted[id].id = id; - dist_base_info_sorted[id].size = dist_t->size; - dist_base_info_sorted[id].needs_size = true; + info[id].name = btf__name_by_offset(r->dist_base_btf, dist_t->name_off); + info[id].id = id; + info[id].size = dist_t->size; + info[id].needs_size = true; } - qsort(dist_base_info_sorted, r->nr_dist_base_types, sizeof(*dist_base_info_sorted), - cmp_btf_name_size); + qsort(info, r->nr_dist_base_types, sizeof(*info), cmp_btf_name_size); /* Mark distilled base struct/union members of split BTF structs/unions * in id_map with BTF_IS_EMBEDDED; this signals that these types - * need to match both name and size, otherwise embeddding the base + * need to match both name and size, otherwise embedding the base * struct/union in the split type is invalid. */ for (id = r->nr_dist_base_types; id < r->nr_split_types; id++) { @@ -216,8 +214,7 @@ static int btf_relocate_map_distilled_base(struct btf_relocate *r) /* Now search base BTF for matching distilled base BTF types. */ for (id = 1; id < r->nr_base_types; id++) { - struct btf_name_info *dist_name_info, *dist_name_info_next = NULL; - struct btf_name_info base_name_info = {}; + struct btf_name_info *dist_info, base_info = {}; int dist_kind, base_kind; base_t = btf_type_by_id(r->base_btf, id); @@ -225,16 +222,16 @@ static int btf_relocate_map_distilled_base(struct btf_relocate *r) if (!base_t->name_off) continue; base_kind = btf_kind(base_t); - base_name_info.id = id; - base_name_info.name = btf__name_by_offset(r->base_btf, base_t->name_off); + base_info.id = id; + base_info.name = btf__name_by_offset(r->base_btf, base_t->name_off); switch (base_kind) { case BTF_KIND_INT: case BTF_KIND_FLOAT: case BTF_KIND_ENUM: case BTF_KIND_ENUM64: /* These types should match both name and size */ - base_name_info.needs_size = true; - base_name_info.size = base_t->size; + base_info.needs_size = true; + base_info.size = base_t->size; break; case BTF_KIND_FWD: /* No size considerations for fwds. */ @@ -248,31 +245,24 @@ static int btf_relocate_map_distilled_base(struct btf_relocate *r) * unless corresponding _base_ types to match them are * missing. */ - base_name_info.needs_size = base_name_cnt[base_t->name_off] > 1; - base_name_info.size = base_t->size; + base_info.needs_size = base_name_cnt[base_t->name_off] > 1; + base_info.size = base_t->size; break; default: continue; } /* iterate over all matching distilled base types */ - for (dist_name_info = search_btf_name_size(&base_name_info, dist_base_info_sorted, - r->nr_dist_base_types); - dist_name_info != NULL; dist_name_info = dist_name_info_next) { - /* Are there more distilled matches to process after - * this one? - */ - dist_name_info_next = dist_name_info + 1; - if (dist_name_info_next >= dist_base_info_sorted_end || - cmp_btf_name_size(&base_name_info, dist_name_info_next)) - dist_name_info_next = NULL; - - if (!dist_name_info->id || dist_name_info->id > r->nr_dist_base_types) { + for (dist_info = search_btf_name_size(&base_info, info, r->nr_dist_base_types); + dist_info != NULL && dist_info < info_end && + cmp_btf_name_size(&base_info, dist_info) == 0; + dist_info++) { + if (!dist_info->id || dist_info->id >= r->nr_dist_base_types) { pr_warn("base BTF id [%d] maps to invalid distilled base BTF id [%d]\n", - id, dist_name_info->id); + id, dist_info->id); err = -EINVAL; goto done; } - dist_t = btf_type_by_id(r->dist_base_btf, dist_name_info->id); + dist_t = btf_type_by_id(r->dist_base_btf, dist_info->id); dist_kind = btf_kind(dist_t); /* Validate that the found distilled type is compatible. @@ -319,15 +309,15 @@ static int btf_relocate_map_distilled_base(struct btf_relocate *r) /* size verification is required for embedded * struct/unions. */ - if (r->id_map[dist_name_info->id] == BTF_IS_EMBEDDED && + if (r->id_map[dist_info->id] == BTF_IS_EMBEDDED && base_t->size != dist_t->size) continue; break; default: continue; } - if (r->id_map[dist_name_info->id] && - r->id_map[dist_name_info->id] != BTF_IS_EMBEDDED) { + if (r->id_map[dist_info->id] && + r->id_map[dist_info->id] != BTF_IS_EMBEDDED) { /* we already have a match; this tells us that * multiple base types of the same name * have the same size, since for cases where @@ -337,13 +327,13 @@ static int btf_relocate_map_distilled_base(struct btf_relocate *r) * to in base BTF, so error out. */ pr_warn("distilled base BTF type '%s' [%u], size %u has multiple candidates of the same size (ids [%u, %u]) in base BTF\n", - base_name_info.name, dist_name_info->id, - base_t->size, id, r->id_map[dist_name_info->id]); + base_info.name, dist_info->id, + base_t->size, id, r->id_map[dist_info->id]); err = -EINVAL; goto done; } /* map id and name */ - r->id_map[dist_name_info->id] = id; + r->id_map[dist_info->id] = id; r->str_map[dist_t->name_off] = base_t->name_off; } } @@ -362,7 +352,7 @@ static int btf_relocate_map_distilled_base(struct btf_relocate *r) } done: free(base_name_cnt); - free(dist_base_info_sorted); + free(info); return err; } -- 2.34.1