kernel/linux.git/net/bpf, branch v5.15.209

bpf: reject short IPv4/IPv6 inputs in bpf_prog_test_run_skb

2026-06-01T15:35:29+00:00

[ Upstream commit 12bec2bd4b76d81c5d3996bd14ec1b7f4d983747 ] bpf_prog_test_run_skb() calls eth_type_trans() first and then uses skb->protocol to initialize sk family and address fields for the test run. For IPv4 and IPv6 packets, it may access ip_hdr(skb) or ipv6_hdr(skb) even when the provided test input only contains an Ethernet header. Reject the input earlier if the Ethernet frame carries IPv4/IPv6 EtherType but the L3 header is too short. Fold the IPv4/IPv6 header length checks into the existing protocol switch and return -EINVAL before accessing the network headers. Fixes: fa5cb548ced6 ("bpf: Setup socket family and addresses in bpf_prog_test_run_skb") Reported-by: syzbot+619b9ef527f510a57cfc@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=619b9ef527f510a57cfc Signed-off-by: Sun Jian Link: https://lore.kernel.org/r/20260408034623.180320-2-sun.jian.kdev@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin

bpf: Do not let BPF test infra emit invalid GSO types to stack

2026-02-06T15:41:58+00:00

commit 04a899573fb87273a656f178b5f920c505f68875 upstream. Yinhao et al. reported that their fuzzer tool was able to trigger a skb_warn_bad_offload() from netif_skb_features() -> gso_features_check(). When a BPF program - triggered via BPF test infra - pushes the packet to the loopback device via bpf_clone_redirect() then mentioned offload warning can be seen. GSO-related features are then rightfully disabled. We get into this situation due to convert___skb_to_skb() setting gso_segs and gso_size but not gso_type. Technically, it makes sense that this warning triggers since the GSO properties are malformed due to the gso_type. Potentially, the gso_type could be marked non-trustworthy through setting it at least to SKB_GSO_DODGY without any other specific assumptions, but that also feels wrong given we should not go further into the GSO engine in the first place. The checks were added in 121d57af308d ("gso: validate gso_type in GSO handlers") because there were malicious (syzbot) senders that combine a protocol with a non-matching gso_type. If we would want to drop such packets, gso_features_check() currently only returns feature flags via netif_skb_features(), so one location for potentially dropping such skbs could be validate_xmit_unreadable_skb(), but then otoh it would be an additional check in the fast-path for a very corner case. Given bpf_clone_redirect() is the only place where BPF test infra could emit such packets, lets reject them right there. Fixes: 850a88cc4096 ("bpf: Expose __sk_buff wire_len/gso_segs to BPF_PROG_TEST_RUN") Fixes: cf62089b0edd ("bpf: Add gso_size to __sk_buff") Reported-by: Yinhao Hu Reported-by: Kaiyan Mei Reported-by: Dongliang Mu Signed-off-by: Daniel Borkmann Signed-off-by: Martin KaFai Lau Link: https://patch.msgid.link/20251020075441.127980-1-daniel@iogearbox.net Signed-off-by: Shung-Hsi Yu Signed-off-by: Greg Kroah-Hartman

bpf: Set run context for rawtp test_run callback

2024-07-05T07:14:06+00:00

[ Upstream commit d0d1df8ba18abc57f28fb3bc053b2bf319367f2c ] syzbot reported crash when rawtp program executed through the test_run interface calls bpf_get_attach_cookie helper or any other helper that touches task->bpf_ctx pointer. Setting the run context (task->bpf_ctx pointer) for test_run callback. Fixes: 7adfc6c9b315 ("bpf: Add bpf_get_attach_cookie() BPF helper to access bpf_cookie value") Reported-by: syzbot+3ab78ff125b7979e45f9@syzkaller.appspotmail.com Signed-off-by: Jiri Olsa Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Closes: https://syzkaller.appspot.com/bug?extid=3ab78ff125b7979e45f9 Link: https://lore.kernel.org/bpf/20240604150024.359247-1-jolsa@kernel.org Signed-off-by: Sasha Levin

bpf: Move skb->len == 0 checks into __bpf_redirect

2022-12-31T12:14:11+00:00

[ Upstream commit 114039b342014680911c35bd6b72624180fd669a ] To avoid potentially breaking existing users. Both mac/no-mac cases have to be amended; mac_header >= network_header is not enough (verified with a new test, see next patch). Fixes: fd1894224407 ("bpf: Don't redirect packets with invalid pkt_len") Signed-off-by: Stanislav Fomichev Link: https://lore.kernel.org/r/20221121180340.1983627-1-sdf@google.com Signed-off-by: Martin KaFai Lau Signed-off-by: Sasha Levin

bpf, test_run: Fix alignment problem in bpf_prog_test_run_skb()

2022-11-26T08:24:35+00:00

[ Upstream commit d3fd203f36d46aa29600a72d57a1b61af80e4a25 ] We got a syzkaller problem because of aarch64 alignment fault if KFENCE enabled. When the size from user bpf program is an odd number, like 399, 407, etc, it will cause the struct skb_shared_info's unaligned access. As seen below: BUG: KFENCE: use-after-free read in __skb_clone+0x23c/0x2a0 net/core/skbuff.c:1032 Use-after-free read at 0xffff6254fffac077 (in kfence-#213): __lse_atomic_add arch/arm64/include/asm/atomic_lse.h:26 [inline] arch_atomic_add arch/arm64/include/asm/atomic.h:28 [inline] arch_atomic_inc include/linux/atomic-arch-fallback.h:270 [inline] atomic_inc include/asm-generic/atomic-instrumented.h:241 [inline] __skb_clone+0x23c/0x2a0 net/core/skbuff.c:1032 skb_clone+0xf4/0x214 net/core/skbuff.c:1481 ____bpf_clone_redirect net/core/filter.c:2433 [inline] bpf_clone_redirect+0x78/0x1c0 net/core/filter.c:2420 bpf_prog_d3839dd9068ceb51+0x80/0x330 bpf_dispatcher_nop_func include/linux/bpf.h:728 [inline] bpf_test_run+0x3c0/0x6c0 net/bpf/test_run.c:53 bpf_prog_test_run_skb+0x638/0xa7c net/bpf/test_run.c:594 bpf_prog_test_run kernel/bpf/syscall.c:3148 [inline] __do_sys_bpf kernel/bpf/syscall.c:4441 [inline] __se_sys_bpf+0xad0/0x1634 kernel/bpf/syscall.c:4381 kfence-#213: 0xffff6254fffac000-0xffff6254fffac196, size=407, cache=kmalloc-512 allocated by task 15074 on cpu 0 at 1342.585390s: kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:675 [inline] bpf_test_init.isra.0+0xac/0x290 net/bpf/test_run.c:191 bpf_prog_test_run_skb+0x11c/0xa7c net/bpf/test_run.c:512 bpf_prog_test_run kernel/bpf/syscall.c:3148 [inline] __do_sys_bpf kernel/bpf/syscall.c:4441 [inline] __se_sys_bpf+0xad0/0x1634 kernel/bpf/syscall.c:4381 __arm64_sys_bpf+0x50/0x60 kernel/bpf/syscall.c:4381 To fix the problem, we adjust @size so that (@size + @hearoom) is a multiple of SMP_CACHE_BYTES. So we make sure the struct skb_shared_info is aligned to a cache line. Fixes: 1cf1cae963c2 ("bpf: introduce BPF_PROG_TEST_RUN command") Signed-off-by: Baisong Zhong Signed-off-by: Daniel Borkmann Cc: Eric Dumazet Link: https://lore.kernel.org/bpf/20221102081620.1465154-1-zhongbaisong@huawei.com Signed-off-by: Sasha Levin

bpf: Don't redirect packets with invalid pkt_len

2022-09-05T08:30:07+00:00

commit fd1894224407c484f652ad456e1ce423e89bb3eb upstream. Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any skbs, that is, the flow->head is null. The root cause, as the [2] says, is because that bpf_prog_test_run_skb() run a bpf prog which redirects empty skbs. So we should determine whether the length of the packet modified by bpf prog or others like bpf_prog_test is valid before forwarding it directly. LINK: [1] https://syzkaller.appspot.com/bug?id=0b84da80c2917757915afa89f7738a9d16ec96c5 LINK: [2] https://www.spinics.net/lists/netdev/msg777503.html Reported-by: syzbot+7a12909485b94426aceb@syzkaller.appspotmail.com Signed-off-by: Zhengchao Shao Reviewed-by: Stanislav Fomichev Link: https://lore.kernel.org/r/20220715115559.139691-1-shaozhengchao@huawei.com Signed-off-by: Alexei Starovoitov Signed-off-by: Greg Kroah-Hartman

bpf: Make remote_port field in struct bpf_sk_lookup 16-bit wide

2022-04-13T18:59:25+00:00

commit 9a69e2b385f443f244a7e8b8bcafe5ccfb0866b4 upstream. remote_port is another case of a BPF context field documented as a 32-bit value in network byte order for which the BPF context access converter generates a load of a zero-padded 16-bit integer in network byte order. First such case was dst_port in bpf_sock which got addressed in commit 4421a582718a ("bpf: Make dst_port field in struct bpf_sock 16-bit wide"). Loading 4-bytes from the remote_port offset and converting the value with bpf_ntohl() leads to surprising results, as the expected value is shifted by 16 bits. Reduce the confusion by splitting the field in two - a 16-bit field holding a big-endian integer, and a 16-bit zero-padding anonymous field that follows it. Suggested-by: Alexei Starovoitov Signed-off-by: Jakub Sitnicki Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20220209184333.654927-2-jakub@cloudflare.com Signed-off-by: Greg Kroah-Hartman

bpf, test, cgroup: Use sk_{alloc,free} for test cases

2021-09-28T07:29:28+00:00

BPF test infra has some hacks in place which kzalloc() a socket and perform minimum init via sock_net_set() and sock_init_data(). As a result, the sk's skcd->cgroup is NULL since it didn't go through proper initialization as it would have been the case from sk_alloc(). Rather than re-adding a NULL test in sock_cgroup_ptr() just for this, use sk_{alloc,free}() pair for the test socket. The latter also allows to get rid of the bpf_sk_storage_free() special case. Fixes: 8520e224f547 ("bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed mode") Fixes: b7a1848e8398 ("bpf: add BPF_PROG_TEST_RUN support for flow dissector") Fixes: 2cb494a36c98 ("bpf: add tests for direct packet access from CGROUP_SKB") Reported-by: syzbot+664b58e9a40fbb2cec71@syzkaller.appspotmail.com Reported-by: syzbot+33f36d0754d4c5c0e102@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Tested-by: syzbot+664b58e9a40fbb2cec71@syzkaller.appspotmail.com Tested-by: syzbot+33f36d0754d4c5c0e102@syzkaller.appspotmail.com Link: https://lore.kernel.org/bpf/20210927123921.21535-2-daniel@iogearbox.net

bpf: Refactor BPF_PROG_RUN into a function

2021-08-16T22:45:07+00:00

Turn BPF_PROG_RUN into a proper always inlined function. No functional and performance changes are intended, but it makes it much easier to understand what's going on with how BPF programs are actually get executed. It's more obvious what types and callbacks are expected. Also extra () around input parameters can be dropped, as well as `__` variable prefixes intended to avoid naming collisions, which makes the code simpler to read and write. This refactoring also highlighted one extra issue. BPF_PROG_RUN is both a macro and an enum value (BPF_PROG_RUN == BPF_PROG_TEST_RUN). Turning BPF_PROG_RUN into a function causes naming conflict compilation error. So rename BPF_PROG_RUN into lower-case bpf_prog_run(), similar to bpf_prog_run_xdp(), bpf_prog_run_pin_on_cpu(), etc. All existing callers of BPF_PROG_RUN, the macro, are switched to bpf_prog_run() explicitly. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20210815070609.987780-2-andrii@kernel.org

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2021-08-13T13:41:22+00:00

Conflicts: drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h 9e26680733d5 ("bnxt_en: Update firmware call to retrieve TX PTP timestamp") 9e518f25802c ("bnxt_en: 1PPS functions to configure TSIO pins") 099fdeda659d ("bnxt_en: Event handler for PPS events") kernel/bpf/helpers.c include/linux/bpf-cgroup.h a2baf4e8bb0f ("bpf: Fix potentially incorrect results with bpf_get_local_storage()") c7603cfa04e7 ("bpf: Add ambient BPF runtime context stored in current") drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c 5957cc557dc5 ("net/mlx5: Set all field of mlx5_irq before inserting it to the xarray") 2d0b41a37679 ("net/mlx5: Refcount mlx5_irq with integer") MAINTAINERS 7b637cd52f02 ("MAINTAINERS: fix Microchip CAN BUS Analyzer Tool entry typo") 7d901a1e878a ("net: phy: add Maxlinear GPY115/21x/24x driver") Signed-off-by: Jakub Kicinski