diff options
| -rw-r--r-- | kernel/bpf/verifier.c | 7 | ||||
| -rw-r--r-- | net/core/filter.c | 24 |
2 files changed, 21 insertions, 10 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 799b2451ef2d..b914fbe1383e 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -4205,7 +4205,12 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) } if (insn->imm == BPF_FUNC_redirect_map) { - u64 addr = (unsigned long)prog; + /* Note, we cannot use prog directly as imm as subsequent + * rewrites would still change the prog pointer. The only + * stable address we can use is aux, which also works with + * prog clones during blinding. + */ + u64 addr = (unsigned long)prog->aux; struct bpf_insn r4_ld[] = { BPF_LD_IMM64(BPF_REG_4, addr), *insn, diff --git a/net/core/filter.c b/net/core/filter.c index 24dd33dd9f04..82edad58d066 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -1794,7 +1794,7 @@ struct redirect_info { u32 flags; struct bpf_map *map; struct bpf_map *map_to_flush; - const struct bpf_prog *map_owner; + unsigned long map_owner; }; static DEFINE_PER_CPU(struct redirect_info, redirect_info); @@ -2500,11 +2500,17 @@ void xdp_do_flush_map(void) } EXPORT_SYMBOL_GPL(xdp_do_flush_map); +static inline bool xdp_map_invalid(const struct bpf_prog *xdp_prog, + unsigned long aux) +{ + return (unsigned long)xdp_prog->aux != aux; +} + static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, struct bpf_prog *xdp_prog) { struct redirect_info *ri = this_cpu_ptr(&redirect_info); - const struct bpf_prog *map_owner = ri->map_owner; + unsigned long map_owner = ri->map_owner; struct bpf_map *map = ri->map; struct net_device *fwd = NULL; u32 index = ri->ifindex; @@ -2512,9 +2518,9 @@ static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, ri->ifindex = 0; ri->map = NULL; - ri->map_owner = NULL; + ri->map_owner = 0; - if (unlikely(map_owner != xdp_prog)) { + if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) { err = -EFAULT; map = NULL; goto err; @@ -2574,7 +2580,7 @@ int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, struct bpf_prog *xdp_prog) { struct redirect_info *ri = this_cpu_ptr(&redirect_info); - const struct bpf_prog *map_owner = ri->map_owner; + unsigned long map_owner = ri->map_owner; struct bpf_map *map = ri->map; struct net_device *fwd = NULL; u32 index = ri->ifindex; @@ -2583,10 +2589,10 @@ int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, ri->ifindex = 0; ri->map = NULL; - ri->map_owner = NULL; + ri->map_owner = 0; if (map) { - if (unlikely(map_owner != xdp_prog)) { + if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) { err = -EFAULT; map = NULL; goto err; @@ -2632,7 +2638,7 @@ BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags) ri->ifindex = ifindex; ri->flags = flags; ri->map = NULL; - ri->map_owner = NULL; + ri->map_owner = 0; return XDP_REDIRECT; } @@ -2646,7 +2652,7 @@ static const struct bpf_func_proto bpf_xdp_redirect_proto = { }; BPF_CALL_4(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags, - const struct bpf_prog *, map_owner) + unsigned long, map_owner) { struct redirect_info *ri = this_cpu_ptr(&redirect_info); |