kernel/linux.git/tools/include/uapi, branch v6.1.168

asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch

2025-12-06T21:12:34+00:00

[ Upstream commit 8386f58f8deda81110283798a387fb53ec21957c ] Now we specify the minimal version of GCC as 5.1 and Clang/LLVM as 11.0.0 in Documentation/process/changes.rst, __CHAR_BIT__ and __SIZEOF_LONG__ are usable, it is probably fine to unify the definition of __BITS_PER_LONG as (__CHAR_BIT__ * __SIZEOF_LONG__) in asm-generic uapi bitsperlong.h. In order to keep safe and avoid regression, only unify uapi bitsperlong.h for some archs such as arm64, riscv and loongarch which are using newer toolchains that have the definitions of __CHAR_BIT__ and __SIZEOF_LONG__. Suggested-by: Xi Ruoyao Link: https://lore.kernel.org/all/d3e255e4746de44c9903c4433616d44ffcf18d1b.camel@xry111.site/ Suggested-by: Arnd Bergmann Link: https://lore.kernel.org/linux-arch/a3a4f48a-07d4-4ed9-bc53-5d383428bdd2@app.fastmail.com/ Signed-off-by: Tiezhu Yang Signed-off-by: Arnd Bergmann Signed-off-by: Sasha Levin

bonding: Add independent control state machine

2025-08-28T14:26:18+00:00

[ Upstream commit 240fd405528bbf7fafa0559202ca7aa524c9cd96 ] Add support for the independent control state machine per IEEE 802.1AX-2008 5.4.15 in addition to the existing implementation of the coupled control state machine. Introduces two new states, AD_MUX_COLLECTING and AD_MUX_DISTRIBUTING in the LACP MUX state machine for separated handling of an initial Collecting state before the Collecting and Distributing state. This enables a port to be in a state where it can receive incoming packets while not still distributing. This is useful for reducing packet loss when a port begins distributing before its partner is able to collect. Added new functions such as bond_set_slave_tx_disabled_flags and bond_set_slave_rx_enabled_flags to precisely manage the port's collecting and distributing states. Previously, there was no dedicated method to disable TX while keeping RX enabled, which this patch addresses. Note that the regular flow process in the kernel's bonding driver remains unaffected by this patch. The extension requires explicit opt-in by the user (in order to ensure no disruptions for existing setups) via netlink support using the new bonding parameter coupled_control. The default value for coupled_control is set to 1 so as to preserve existing behaviour. Signed-off-by: Aahil Awatramani Reviewed-by: Hangbin Liu Link: https://lore.kernel.org/r/20240202175858.1573852-1-aahila@google.com Signed-off-by: Paolo Abeni Stable-dep-of: 0599640a21e9 ("bonding: send LACPDUs periodically in passive mode after receiving partner's LACPDU") Signed-off-by: Sasha Levin

bpf: Fix L4 csum update on IPv6 in CHECKSUM_COMPLETE

2025-06-27T10:07:38+00:00

commit ead7f9b8de65632ef8060b84b0c55049a33cfea1 upstream. In Cilium, we use bpf_csum_diff + bpf_l4_csum_replace to, among other things, update the L4 checksum after reverse SNATing IPv6 packets. That use case is however not currently supported and leads to invalid skb->csum values in some cases. This patch adds support for IPv6 address changes in bpf_l4_csum_update via a new flag. When calling bpf_l4_csum_replace in Cilium, it ends up calling inet_proto_csum_replace_by_diff: 1: void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb, 2: __wsum diff, bool pseudohdr) 3: { 4: if (skb->ip_summed != CHECKSUM_PARTIAL) { 5: csum_replace_by_diff(sum, diff); 6: if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr) 7: skb->csum = ~csum_sub(diff, skb->csum); 8: } else if (pseudohdr) { 9: *sum = ~csum_fold(csum_add(diff, csum_unfold(*sum))); 10: } 11: } The bug happens when we're in the CHECKSUM_COMPLETE state. We've just updated one of the IPv6 addresses. The helper now updates the L4 header checksum on line 5. Next, it updates skb->csum on line 7. It shouldn't. For an IPv6 packet, the updates of the IPv6 address and of the L4 checksum will cancel each other. The checksums are set such that computing a checksum over the packet including its checksum will result in a sum of 0. So the same is true here when we update the L4 checksum on line 5. We'll update it as to cancel the previous IPv6 address update. Hence skb->csum should remain untouched in this case. The same bug doesn't affect IPv4 packets because, in that case, three fields are updated: the IPv4 address, the IP checksum, and the L4 checksum. The change to the IPv4 address and one of the checksums still cancel each other in skb->csum, but we're left with one checksum update and should therefore update skb->csum accordingly. That's exactly what inet_proto_csum_replace_by_diff does. This special case for IPv6 L4 checksums is also described atop inet_proto_csum_replace16, the function we should be using in this case. This patch introduces a new bpf_l4_csum_replace flag, BPF_F_IPV6, to indicate that we're updating the L4 checksum of an IPv6 packet. When the flag is set, inet_proto_csum_replace_by_diff will skip the skb->csum update. Fixes: 7d672345ed295 ("bpf: add generic bpf_csum_diff helper") Signed-off-by: Paul Chaignon Acked-by: Daniel Borkmann Link: https://patch.msgid.link/96a6bc3a443e6f0b21ff7b7834000e17fb549e05.1748509484.git.paul.chaignon@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Paul Chaignon Signed-off-by: Greg Kroah-Hartman

stddef: make __struct_group() UAPI C++-friendly

2025-01-02T09:30:51+00:00

[ Upstream commit 724c6ce38bbaeb4b3f109b0e066d6c0ecd15446c ] For the most part of the C++ history, it couldn't have type declarations inside anonymous unions for different reasons. At the same time, __struct_group() relies on the latters, so when the @TAG argument is not empty, C++ code doesn't want to build (even under `extern "C"`): ../linux/include/uapi/linux/pkt_cls.h:25:24: error: 'struct tc_u32_sel::::tc_u32_sel_hdr,' invalid; an anonymous union may only have public non-static data members [-fpermissive] The safest way to fix this without trying to switch standards (which is impossible in UAPI anyway) etc., is to disable tag declaration for that language. This won't break anything since for now it's not buildable at all. Use a separate definition for __struct_group() when __cplusplus is defined to mitigate the error, including the version from tools/. Fixes: 50d7bd38c3aa ("stddef: Introduce struct_group() helper macro") Reported-by: Christopher Ferris Closes: https://lore.kernel.org/linux-hardening/Z1HZpe3WE5As8UAz@google.com Suggested-by: Kees Cook # __struct_group_tag() Signed-off-by: Alexander Lobakin Reviewed-by: Gustavo A. R. Silva Link: https://lore.kernel.org/r/20241219135734.2130002-1-aleksander.lobakin@intel.com Signed-off-by: Kees Cook Signed-off-by: Sasha Levin

bpf: Replace bpf_lpm_trie_key 0-length array with flexible array

2024-08-29T15:30:22+00:00

[ Upstream commit 896880ff30866f386ebed14ab81ce1ad3710cfc4 ] Replace deprecated 0-length array in struct bpf_lpm_trie_key with flexible array. Found with GCC 13: ../kernel/bpf/lpm_trie.c:207:51: warning: array subscript i is outside array bounds of 'const __u8[0]' {aka 'const unsigned char[]'} [-Warray-bounds=] 207 | *(__be16 *)&key->data[i]); | ^~~~~~~~~~~~~ ../include/uapi/linux/swab.h:102:54: note: in definition of macro '__swab16' 102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) | ^ ../include/linux/byteorder/generic.h:97:21: note: in expansion of macro '__be16_to_cpu' 97 | #define be16_to_cpu __be16_to_cpu | ^~~~~~~~~~~~~ ../kernel/bpf/lpm_trie.c:206:28: note: in expansion of macro 'be16_to_cpu' 206 | u16 diff = be16_to_cpu(*(__be16 *)&node->data[i] ^ | ^~~~~~~~~~~ In file included from ../include/linux/bpf.h:7: ../include/uapi/linux/bpf.h:82:17: note: while referencing 'data' 82 | __u8 data[0]; /* Arbitrary size */ | ^~~~ And found at run-time under CONFIG_FORTIFY_SOURCE: UBSAN: array-index-out-of-bounds in kernel/bpf/lpm_trie.c:218:49 index 0 is out of range for type '__u8 [*]' Changing struct bpf_lpm_trie_key is difficult since has been used by userspace. For example, in Cilium: struct egress_gw_policy_key { struct bpf_lpm_trie_key lpm_key; __u32 saddr; __u32 daddr; }; While direct references to the "data" member haven't been found, there are static initializers what include the final member. For example, the "{}" here: struct egress_gw_policy_key in_key = { .lpm_key = { 32 + 24, {} }, .saddr = CLIENT_IP, .daddr = EXTERNAL_SVC_IP & 0Xffffff, }; To avoid the build time and run time warnings seen with a 0-sized trailing array for struct bpf_lpm_trie_key, introduce a new struct that correctly uses a flexible array for the trailing bytes, struct bpf_lpm_trie_key_u8. As part of this, include the "header" portion (which is just the "prefixlen" member), so it can be used by anything building a bpf_lpr_trie_key that has trailing members that aren't a u8 flexible array (like the self-test[1]), which is named struct bpf_lpm_trie_key_hdr. Unfortunately, C++ refuses to parse the __struct_group() helper, so it is not possible to define struct bpf_lpm_trie_key_hdr directly in struct bpf_lpm_trie_key_u8, so we must open-code the union directly. Adjust the kernel code to use struct bpf_lpm_trie_key_u8 through-out, and for the selftest to use struct bpf_lpm_trie_key_hdr. Add a comment to the UAPI header directing folks to the two new options. Reported-by: Mark Rutland Signed-off-by: Kees Cook Signed-off-by: Daniel Borkmann Acked-by: Gustavo A. R. Silva Closes: https://paste.debian.net/hidden/ca500597/ Link: https://lore.kernel.org/all/202206281009.4332AA33@keescook/ [1] Link: https://lore.kernel.org/bpf/20240222155612.it.533-kees@kernel.org Stable-dep-of: 59f2f841179a ("bpf: Avoid kfree_rcu() under lock in bpf_lpm_trie.") Signed-off-by: Sasha Levin

bpf: Pack struct bpf_fib_lookup

2024-06-12T09:03:08+00:00

[ Upstream commit f91717007217d975aa975ddabd91ae1a107b9bff ] The struct bpf_fib_lookup is supposed to be of size 64. A recent commit 59b418c7063d ("bpf: Add a check for struct bpf_fib_lookup size") added a static assertion to check this property so that future changes to the structure will not accidentally break this assumption. As it immediately turned out, on some 32-bit arm systems, when AEABI=n, the total size of the structure was equal to 68, see [1]. This happened because the bpf_fib_lookup structure contains a union of two 16-bit fields: union { __u16 tot_len; __u16 mtu_result; }; which was supposed to compile to a 16-bit-aligned 16-bit field. On the aforementioned setups it was instead both aligned and padded to 32-bits. Declare this inner union as __attribute__((packed, aligned(2))) such that it always is of size 2 and is aligned to 16 bits. [1] https://lore.kernel.org/all/CA+G9fYtsoP51f-oP_Sp5MOq-Ffv8La2RztNpwvE6+R1VtFiLrw@mail.gmail.com/#t Reported-by: Naresh Kamboju Fixes: e1850ea9bd9e ("bpf: bpf_fib_lookup return MTU value as output when looked up") Signed-off-by: Anton Protopopov Signed-off-by: Andrii Nakryiko Reviewed-by: Alexander Lobakin Acked-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20240403123303.1452184-1-aspsk@isovalent.com Signed-off-by: Sasha Levin

bpf: Derive source IP addr via bpf_*_fib_lookup()

2024-03-06T14:45:20+00:00

commit dab4e1f06cabb6834de14264394ccab197007302 upstream. Extend the bpf_fib_lookup() helper by making it to return the source IPv4/IPv6 address if the BPF_FIB_LOOKUP_SRC flag is set. For example, the following snippet can be used to derive the desired source IP address: struct bpf_fib_lookup p = { .ipv4_dst = ip4->daddr }; ret = bpf_skb_fib_lookup(skb, p, sizeof(p), BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_SKIP_NEIGH); if (ret != BPF_FIB_LKUP_RET_SUCCESS) return TC_ACT_SHOT; /* the p.ipv4_src now contains the source address */ The inability to derive the proper source address may cause malfunctions in BPF-based dataplanes for hosts containing netdevs with more than one routable IP address or for multi-homed hosts. For example, Cilium implements packet masquerading in BPF. If an egressing netdev to which the Cilium's BPF prog is attached has multiple IP addresses, then only one [hardcoded] IP address can be used for masquerading. This breaks connectivity if any other IP address should have been selected instead, for example, when a public and private addresses are attached to the same egress interface. The change was tested with Cilium [1]. Nikolay Aleksandrov helped to figure out the IPv6 addr selection. [1]: https://github.com/cilium/cilium/pull/28283 Signed-off-by: Martynas Pumputis Link: https://lore.kernel.org/r/20231007081415.33502-2-m@lambda.lt Signed-off-by: Martin KaFai Lau Signed-off-by: Daniel Borkmann Signed-off-by: Greg Kroah-Hartman

bpf: Add table ID to bpf_fib_lookup BPF helper

2024-03-06T14:45:20+00:00

commit 8ad77e72caae22a1ddcfd0c03f2884929e93b7a4 upstream. Add ability to specify routing table ID to the `bpf_fib_lookup` BPF helper. A new field `tbid` is added to `struct bpf_fib_lookup` used as parameters to the `bpf_fib_lookup` BPF helper. When the helper is called with the `BPF_FIB_LOOKUP_DIRECT` and `BPF_FIB_LOOKUP_TBID` flags the `tbid` field in `struct bpf_fib_lookup` will be used as the table ID for the fib lookup. If the `tbid` does not exist the fib lookup will fail with `BPF_FIB_LKUP_RET_NOT_FWDED`. The `tbid` field becomes a union over the vlan related output fields in `struct bpf_fib_lookup` and will be zeroed immediately after usage. This functionality is useful in containerized environments. For instance, if a CNI wants to dictate the next-hop for traffic leaving a container it can create a container-specific routing table and perform a fib lookup against this table in a "host-net-namespace-side" TC program. This functionality also allows `ip rule` like functionality at the TC layer, allowing an eBPF program to pick a routing table based on some aspect of the sk_buff. As a concrete use case, this feature will be used in Cilium's SRv6 L3VPN datapath. When egress traffic leaves a Pod an eBPF program attached by Cilium will determine which VRF the egress traffic should target, and then perform a FIB lookup in a specific table representing this VRF's FIB. Signed-off-by: Louis DeLosSantos Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20230505-bpf-add-tbid-fib-lookup-v2-1-0a31c22c748c@gmail.com Signed-off-by: Greg Kroah-Hartman

bpf: Add crosstask check to __bpf_get_stack

2024-01-25T23:27:24+00:00

[ Upstream commit b8e3a87a627b575896e448021e5c2f8a3bc19931 ] Currently get_perf_callchain only supports user stack walking for the current task. Passing the correct *crosstask* param will return 0 frames if the task passed to __bpf_get_stack isn't the current one instead of a single incorrect frame/address. This change passes the correct *crosstask* param but also does a preemptive check in __bpf_get_stack if the task is current and returns -EOPNOTSUPP if it is not. This issue was found using bpf_get_task_stack inside a BPF iterator ("iter/task"), which iterates over all tasks. bpf_get_task_stack works fine for fetching kernel stacks but because get_perf_callchain relies on the caller to know if the requested *task* is the current one (via *crosstask*) it was failing in a confusing way. It might be possible to get user stacks for all tasks utilizing something like access_process_vm but that requires the bpf program calling bpf_get_task_stack to be sleepable and would therefore be a breaking change. Fixes: fa28dcb82a38 ("bpf: Introduce helper bpf_get_task_stack()") Signed-off-by: Jordan Rome Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20231108112334.3433136-1-jordalgo@meta.com Signed-off-by: Sasha Levin

bpf: Add BPF_FIB_LOOKUP_SKIP_NEIGH for bpf_fib_lookup

2023-10-10T20:00:42+00:00

[ Upstream commit 31de4105f00d64570139bc5494a201b0bd57349f ] The bpf_fib_lookup() also looks up the neigh table. This was done before bpf_redirect_neigh() was added. In the use case that does not manage the neigh table and requires bpf_fib_lookup() to lookup a fib to decide if it needs to redirect or not, the bpf prog can depend only on using bpf_redirect_neigh() to lookup the neigh. It also keeps the neigh entries fresh and connected. This patch adds a bpf_fib_lookup flag, SKIP_NEIGH, to avoid the double neigh lookup when the bpf prog always call bpf_redirect_neigh() to do the neigh lookup. The params->smac output is skipped together when SKIP_NEIGH is set because bpf_redirect_neigh() will figure out the smac also. Signed-off-by: Martin KaFai Lau Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20230217205515.3583372-1-martin.lau@linux.dev Stable-dep-of: 5baa0433a15e ("neighbour: fix data-races around n->output") Signed-off-by: Sasha Levin