From: Benjamin Tissoires <bentiss@kernel.org> mainline inclusion from mainline-v6.10-rc1 commit a891711d0166133ec5120615fcf365d9745d82b2 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/17960 CVE: CVE-2026-74314 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- If someone stores both a timer and a workqueue in a hash map, on free, we would walk it twice. Add a check in htab_free_malloced_timers_or_wq and free the timers and workqueues if they are present. Fixes: 246331e3f1ea ("bpf: allow struct bpf_wq to be embedded in arraymaps and hashmaps") Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/bpf/20240430-bpf-next-v3-2-27afe7f3b17c@kernel.org Conflicts: kernel/bpf/hashtab.c [not merged BPF_WORKQUEUE related] Signed-off-by: Pu Lehui <pulehui@huawei.com> --- kernel/bpf/hashtab.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 81db81109e04..eb879fbfb52c 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -225,8 +225,6 @@ static void htab_free_prealloced_timers(struct bpf_htab *htab) u32 num_entries = htab->map.max_entries; int i; - if (!btf_record_has_field(htab->map.record, BPF_TIMER)) - return; if (htab_has_extra_elems(htab)) num_entries += num_possible_cpus(); @@ -234,7 +232,9 @@ static void htab_free_prealloced_timers(struct bpf_htab *htab) struct htab_elem *elem; elem = get_htab_elem(htab, i); - bpf_obj_free_timer(htab->map.record, elem->key + round_up(htab->map.key_size, 8)); + if (btf_record_has_field(htab->map.record, BPF_TIMER)) + bpf_obj_free_timer(htab->map.record, + elem->key + round_up(htab->map.key_size, 8)); cond_resched(); } } @@ -1529,7 +1529,9 @@ static void htab_free_malloced_timers(struct bpf_htab *htab) hlist_nulls_for_each_entry(l, n, head, hash_node) { /* We only free timer on uref dropping to zero */ - bpf_obj_free_timer(htab->map.record, l->key + round_up(htab->map.key_size, 8)); + if (btf_record_has_field(htab->map.record, BPF_TIMER)) + bpf_obj_free_timer(htab->map.record, + l->key + round_up(htab->map.key_size, 8)); } cond_resched_rcu(); } @@ -1541,12 +1543,12 @@ static void htab_map_free_timers(struct bpf_map *map) struct bpf_htab *htab = container_of(map, struct bpf_htab, map); /* We only free timer on uref dropping to zero */ - if (!btf_record_has_field(htab->map.record, BPF_TIMER)) - return; - if (!htab_is_prealloc(htab)) - htab_free_malloced_timers(htab); - else - htab_free_prealloced_timers(htab); + if (btf_record_has_field(htab->map.record, BPF_TIMER)) { + if (!htab_is_prealloc(htab)) + htab_free_malloced_timers(htab); + else + htab_free_prealloced_timers(htab); + } } /* Called when map->refcnt goes to zero, either from workqueue or from syscall */ -- 2.34.1