From: Daniel Borkmann <daniel@iogearbox.net> mainline inclusion from mainline-v6.17-rc1 commit 12df58ad294253ac1d8df0c9bb9cf726397a671d category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ICTB0G CVE: CVE-2025-38502 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Add a cookie to BPF maps to uniquely identify BPF maps for the timespan when the node is up. This is different to comparing a pointer or BPF map id which could get rolled over and reused. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20250730234733.530041-1-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org> Conflicts: include/linux/bpf.h kernel/bpf/syscall.c [The conflicts were due to some minor issue.] Signed-off-by: Xiaomeng Zhang <zhangxiaomeng13@huawei.com> --- include/linux/bpf.h | 1 + kernel/bpf/syscall.c | 6 ++++++ 2 files changed, 7 insertions(+) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 4201bf8e9f5e..0dbeba91e6fc 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -197,6 +197,7 @@ struct bpf_map { enum bpf_prog_type type; bool jited; } owner; + u64 cookie; /* write-once */ }; static inline bool map_value_has_spin_lock(const struct bpf_map *map) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 75ad39edb63c..666d6c7077b6 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -31,6 +31,7 @@ #include <linux/poll.h> #include <linux/bpf-netns.h> #include <linux/rcupdate_trace.h> +#include <linux/cookie.h> #include <linux/bpf_sched.h> #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ @@ -44,6 +45,7 @@ #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) DEFINE_PER_CPU(int, bpf_prog_active); +DEFINE_COOKIE(bpf_map_cookie); static DEFINE_IDR(prog_idr); static DEFINE_SPINLOCK(prog_idr_lock); static DEFINE_IDR(map_idr); @@ -861,6 +863,10 @@ static int map_create(union bpf_attr *attr) if (err < 0) goto free_map; + preempt_disable(); + map->cookie = gen_cookie_next(&bpf_map_cookie); + preempt_enable(); + atomic64_set(&map->refcnt, 1); atomic64_set(&map->usercnt, 1); mutex_init(&map->freeze_mutex); -- 2.34.1