From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- include/net/gtp.h | 86 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 86 insertions(+) create mode 100644 include/net/gtp.h (limited to 'include/net/gtp.h') diff --git a/include/net/gtp.h b/include/net/gtp.h new file mode 100644 index 000000000..c0253c870 --- /dev/null +++ b/include/net/gtp.h @@ -0,0 +1,86 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _GTP_H_ +#define _GTP_H_ + +#include +#include +#include + +/* General GTP protocol related definitions. */ + +#define GTP0_PORT 3386 +#define GTP1U_PORT 2152 + +/* GTP messages types */ +#define GTP_ECHO_REQ 1 /* Echo Request */ +#define GTP_ECHO_RSP 2 /* Echo Response */ +#define GTP_TPDU 255 + +#define GTPIE_RECOVERY 14 + +struct gtp0_header { /* According to GSM TS 09.60. */ + __u8 flags; + __u8 type; + __be16 length; + __be16 seq; + __be16 flow; + __u8 number; + __u8 spare[3]; + __be64 tid; +} __attribute__ ((packed)); + +struct gtp1_header { /* According to 3GPP TS 29.060. */ + __u8 flags; + __u8 type; + __be16 length; + __be32 tid; +} __attribute__ ((packed)); + +struct gtp1_header_long { /* According to 3GPP TS 29.060. */ + __u8 flags; + __u8 type; + __be16 length; + __be32 tid; + __be16 seq; + __u8 npdu; + __u8 next; +} __packed; + +/* GTP Information Element */ +struct gtp_ie { + __u8 tag; + __u8 val; +} __packed; + +struct gtp0_packet { + struct gtp0_header gtp0_h; + struct gtp_ie ie; +} __packed; + +struct gtp1u_packet { + struct gtp1_header_long gtp1u_h; + struct gtp_ie ie; +} __packed; + +struct gtp_pdu_session_info { /* According to 3GPP TS 38.415. */ + u8 pdu_type; + u8 qfi; +}; + +static inline bool netif_is_gtp(const struct net_device *dev) +{ + return dev->rtnl_link_ops && + !strcmp(dev->rtnl_link_ops->kind, "gtp"); +} + +#define GTP1_F_NPDU 0x01 +#define GTP1_F_SEQ 0x02 +#define GTP1_F_EXTHDR 0x04 +#define GTP1_F_MASK 0x07 + +struct gtp_ext_hdr { + __u8 len; + __u8 data[]; +}; + +#endif -- cgit v1.3.1