summaryrefslogtreecommitdiffstats
path: root/kernel/bpf
AgeCommit message (Collapse)Author
2020-09-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
We got slightly different patches removing a double word in a comment in net/ipv4/raw.c - picked the version from net. Simple conflict in drivers/net/ethernet/ibm/ibmvnic.c. Use cached values instead of VNIC login response buffer (following what commit 507ebe6444a4 ("ibmvnic: Fix use-after-free of VNIC login response buffer") did). Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: 1) Use netif_rx_ni() when necessary in batman-adv stack, from Jussi Kivilinna. 2) Fix loss of RTT samples in rxrpc, from David Howells. 3) Memory leak in hns_nic_dev_probe(), from Dignhao Liu. 4) ravb module cannot be unloaded, fix from Yuusuke Ashizuka. 5) We disable BH for too lokng in sctp_get_port_local(), add a cond_resched() here as well, from Xin Long. 6) Fix memory leak in st95hf_in_send_cmd, from Dinghao Liu. 7) Out of bound access in bpf_raw_tp_link_fill_link_info(), from Yonghong Song. 8) Missing of_node_put() in mt7530 DSA driver, from Sumera Priyadarsini. 9) Fix crash in bnxt_fw_reset_task(), from Michael Chan. 10) Fix geneve tunnel checksumming bug in hns3, from Yi Li. 11) Memory leak in rxkad_verify_response, from Dinghao Liu. 12) In tipc, don't use smp_processor_id() in preemptible context. From Tuong Lien. 13) Fix signedness issue in mlx4 memory allocation, from Shung-Hsi Yu. 14) Missing clk_disable_prepare() in gemini driver, from Dan Carpenter. 15) Fix ABI mismatch between driver and firmware in nfp, from Louis Peens. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (110 commits) net/smc: fix sock refcounting in case of termination net/smc: reset sndbuf_desc if freed net/smc: set rx_off for SMCR explicitly net/smc: fix toleration of fake add_link messages tg3: Fix soft lockup when tg3_reset_task() fails. doc: net: dsa: Fix typo in config code sample net: dp83867: Fix WoL SecureOn password nfp: flower: fix ABI mismatch between driver and firmware tipc: fix shutdown() of connectionless socket ipv6: Fix sysctl max for fib_multipath_hash_policy drivers/net/wan/hdlc: Change the default of hard_header_len to 0 net: gemini: Fix another missing clk_disable_unprepare() in probe net: bcmgenet: fix mask check in bcmgenet_validate_flow() amd-xgbe: Add support for new port mode net: usb: dm9601: Add USB ID of Keenetic Plus DSL vhost: fix typo in error message net: ethernet: mlx4: Fix memory allocation in mlx4_buddy_init() pktgen: fix error message with wrong function name net: ethernet: ti: am65-cpsw: fix rmii 100Mbit link mode cxgb4: fix thermal zone device registration ...
2020-09-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2020-09-01 The following pull-request contains BPF updates for your *net-next* tree. There are two small conflicts when pulling, resolve as follows: 1) Merge conflict in tools/lib/bpf/libbpf.c between 88a82120282b ("libbpf: Factor out common ELF operations and improve logging") in bpf-next and 1e891e513e16 ("libbpf: Fix map index used in error message") in net-next. Resolve by taking the hunk in bpf-next: [...] scn = elf_sec_by_idx(obj, obj->efile.btf_maps_shndx); data = elf_sec_data(obj, scn); if (!scn || !data) { pr_warn("elf: failed to get %s map definitions for %s\n", MAPS_ELF_SEC, obj->path); return -EINVAL; } [...] 2) Merge conflict in drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c between 9647c57b11e5 ("xsk: i40e: ice: ixgbe: mlx5: Test for dma_need_sync earlier for better performance") in bpf-next and e20f0dbf204f ("net/mlx5e: RX, Add a prefetch command for small L1_CACHE_BYTES") in net-next. Resolve the two locations by retaining net_prefetch() and taking xsk_buff_dma_sync_for_cpu() from bpf-next. Should look like: [...] xdp_set_data_meta_invalid(xdp); xsk_buff_dma_sync_for_cpu(xdp, rq->xsk_pool); net_prefetch(xdp->data); [...] We've added 133 non-merge commits during the last 14 day(s) which contain a total of 246 files changed, 13832 insertions(+), 3105 deletions(-). The main changes are: 1) Initial support for sleepable BPF programs along with bpf_copy_from_user() helper for tracing to reliably access user memory, from Alexei Starovoitov. 2) Add BPF infra for writing and parsing TCP header options, from Martin KaFai Lau. 3) bpf_d_path() helper for returning full path for given 'struct path', from Jiri Olsa. 4) AF_XDP support for shared umems between devices and queues, from Magnus Karlsson. 5) Initial prep work for full BPF-to-BPF call support in libbpf, from Andrii Nakryiko. 6) Generalize bpf_sk_storage map & add local storage for inodes, from KP Singh. 7) Implement sockmap/hash updates from BPF context, from Lorenz Bauer. 8) BPF xor verification for scalar types & add BPF link iterator, from Yonghong Song. 9) Use target's prog type for BPF_PROG_TYPE_EXT prog verification, from Udip Pant. 10) Rework BPF tracing samples to use libbpf loader, from Daniel T. Lee. 11) Fix xdpsock sample to really cycle through all buffers, from Weqaar Janjua. 12) Improve type safety for tun/veth XDP frame handling, from Maciej Żenczykowski. 13) Various smaller cleanups and improvements all over the place. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-01bpf: {cpu,dev}map: Change various functions return type from int to voidBjörn Töpel
The functions bq_enqueue(), bq_flush_to_queue(), and bq_xmit_all() in {cpu,dev}map.c always return zero. Changing the return type from int to void makes the code easier to follow. Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200901083928.6199-1-bjorn.topel@gmail.com
2020-08-31bpf: Remove bpf_lsm_file_mprotect from sleepable list.Alexei Starovoitov
Technically the bpf programs can sleep while attached to bpf_lsm_file_mprotect, but such programs need to access user memory. So they're in might_fault() category. Which means they cannot be called from file_mprotect lsm hook that takes write lock on mm->mmap_lock. Adjust the test accordingly. Also add might_fault() to __bpf_prog_enter_sleepable() to catch such deadlocks early. Fixes: 1e6c62a88215 ("bpf: Introduce sleepable BPF programs") Fixes: e68a144547fc ("selftests/bpf: Add sleepable tests") Reported-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200831201651.82447-1-alexei.starovoitov@gmail.com
2020-08-31bpf: Fix build without BPF_LSM.Alexei Starovoitov
resolve_btfids doesn't like empty set. Add unused ID when BPF_LSM is off. Fixes: 1e6c62a88215 ("bpf: Introduce sleepable BPF programs") Reported-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Song Liu <songliubraving@fb.com> Acked-by: KP Singh <kpsingh@google.com> Link: https://lore.kernel.org/bpf/20200831163132.66521-1-alexei.starovoitov@gmail.com
2020-08-28bpf: Add bpf_copy_from_user() helper.Alexei Starovoitov
Sleepable BPF programs can now use copy_from_user() to access user memory. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: KP Singh <kpsingh@google.com> Link: https://lore.kernel.org/bpf/20200827220114.69225-4-alexei.starovoitov@gmail.com
2020-08-28bpf: Introduce sleepable BPF programsAlexei Starovoitov
Introduce sleepable BPF programs that can request such property for themselves via BPF_F_SLEEPABLE flag at program load time. In such case they will be able to use helpers like bpf_copy_from_user() that might sleep. At present only fentry/fexit/fmod_ret and lsm programs can request to be sleepable and only when they are attached to kernel functions that are known to allow sleeping. The non-sleepable programs are relying on implicit rcu_read_lock() and migrate_disable() to protect life time of programs, maps that they use and per-cpu kernel structures used to pass info between bpf programs and the kernel. The sleepable programs cannot be enclosed into rcu_read_lock(). migrate_disable() maps to preempt_disable() in non-RT kernels, so the progs should not be enclosed in migrate_disable() as well. Therefore rcu_read_lock_trace is used to protect the life time of sleepable progs. There are many networking and tracing program types. In many cases the 'struct bpf_prog *' pointer itself is rcu protected within some other kernel data structure and the kernel code is using rcu_dereference() to load that program pointer and call BPF_PROG_RUN() on it. All these cases are not touched. Instead sleepable bpf programs are allowed with bpf trampoline only. The program pointers are hard-coded into generated assembly of bpf trampoline and synchronize_rcu_tasks_trace() is used to protect the life time of the program. The same trampoline can hold both sleepable and non-sleepable progs. When rcu_read_lock_trace is held it means that some sleepable bpf program is running from bpf trampoline. Those programs can use bpf arrays and preallocated hash/lru maps. These map types are waiting on programs to complete via synchronize_rcu_tasks_trace(); Updates to trampoline now has to do synchronize_rcu_tasks_trace() and synchronize_rcu_tasks() to wait for sleepable progs to finish and for trampoline assembly to finish. This is the first step of introducing sleepable progs. Eventually dynamically allocated hash maps can be allowed and networking program types can become sleepable too. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: KP Singh <kpsingh@google.com> Link: https://lore.kernel.org/bpf/20200827220114.69225-3-alexei.starovoitov@gmail.com
2020-08-28bpf: Relax max_entries check for most of the inner map typesMartin KaFai Lau
Most of the maps do not use max_entries during verification time. Thus, those map_meta_equal() do not need to enforce max_entries when it is inserted as an inner map during runtime. The max_entries check is removed from the default implementation bpf_map_meta_equal(). The prog_array_map and xsk_map are exception. Its map_gen_lookup uses max_entries to generate inline lookup code. Thus, they will implement its own map_meta_equal() to enforce max_entries. Since there are only two cases now, the max_entries check is not refactored and stays in its own .c file. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200828011813.1970516-1-kafai@fb.com
2020-08-28bpf: Add map_meta_equal map opsMartin KaFai Lau
Some properties of the inner map is used in the verification time. When an inner map is inserted to an outer map at runtime, bpf_map_meta_equal() is currently used to ensure those properties of the inserting inner map stays the same as the verification time. In particular, the current bpf_map_meta_equal() checks max_entries which turns out to be too restrictive for most of the maps which do not use max_entries during the verification time. It limits the use case that wants to replace a smaller inner map with a larger inner map. There are some maps do use max_entries during verification though. For example, the map_gen_lookup in array_map_ops uses the max_entries to generate the inline lookup code. To accommodate differences between maps, the map_meta_equal is added to bpf_map_ops. Each map-type can decide what to check when its map is used as an inner map during runtime. Also, some map types cannot be used as an inner map and they are currently black listed in bpf_map_meta_alloc() in map_in_map.c. It is not unusual that the new map types may not aware that such blacklist exists. This patch enforces an explicit opt-in and only allows a map to be used as an inner map if it has implemented the map_meta_equal ops. It is based on the discussion in [1]. All maps that support inner map has its map_meta_equal points to bpf_map_meta_equal in this patch. A later patch will relax the max_entries check for most maps. bpf_types.h counts 28 map types. This patch adds 23 ".map_meta_equal" by using coccinelle. -5 for BPF_MAP_TYPE_PROG_ARRAY BPF_MAP_TYPE_(PERCPU)_CGROUP_STORAGE BPF_MAP_TYPE_STRUCT_OPS BPF_MAP_TYPE_ARRAY_OF_MAPS BPF_MAP_TYPE_HASH_OF_MAPS The "if (inner_map->inner_map_meta)" check in bpf_map_meta_alloc() is moved such that the same error is returned. [1]: https://lore.kernel.org/bpf/20200522022342.899756-1-kafai@fb.com/ Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200828011806.1970400-1-kafai@fb.com
2020-08-26bpf: Fix a verifier failure with xorYonghong Song
bpf selftest test_progs/test_sk_assign failed with llvm 11 and llvm 12. Compared to llvm 10, llvm 11 and 12 generates xor instruction which is not handled properly in verifier. The following illustrates the problem: 16: (b4) w5 = 0 17: ... R5_w=inv0 ... ... 132: (a4) w5 ^= 1 133: ... R5_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) ... ... 37: (bc) w8 = w5 38: ... R5=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R8_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) ... ... 41: (bc) w3 = w8 42: ... R3_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) ... 45: (56) if w3 != 0x0 goto pc+1 ... R3_w=inv0 ... 46: (b7) r1 = 34 47: R1_w=inv34 R7=pkt(id=0,off=26,r=38,imm=0) 47: (0f) r7 += r1 48: R1_w=invP34 R3_w=inv0 R7_w=pkt(id=0,off=60,r=38,imm=0) 48: (b4) w9 = 0 49: R1_w=invP34 R3_w=inv0 R7_w=pkt(id=0,off=60,r=38,imm=0) 49: (69) r1 = *(u16 *)(r7 +0) invalid access to packet, off=60 size=2, R7(id=0,off=60,r=38) R7 offset is outside of the packet At above insn 132, w5 = 0, but after w5 ^= 1, we give a really conservative value of w5. At insn 45, in reality the condition should be always false. But due to conservative value for w3, the verifier evaluates it could be true and this later leads to verifier failure complaining potential packet out-of-bound access. This patch implemented proper XOR support in verifier. In the above example, we have: 132: R5=invP0 132: (a4) w5 ^= 1 133: R5_w=invP1 ... 37: (bc) w8 = w5 ... 41: (bc) w3 = w8 42: R3_w=invP1 ... 45: (56) if w3 != 0x0 goto pc+1 47: R3_w=invP1 ... processed 353 insns ... and the verifier can verify the program successfully. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200825064608.2017937-1-yhs@fb.com
2020-08-26bpf: verifier: Use target program's type for access verificationsUdip Pant
This patch adds changes in verifier to make decisions such as granting of read / write access or enforcement of return code status based on the program type of the target program while using dynamic program extension (of type BPF_PROG_TYPE_EXT). The BPF_PROG_TYPE_EXT type can be used to extend types such as XDP, SKB and others. Since the BPF_PROG_TYPE_EXT program type on itself is just a placeholder for those, we need this extended check for those extended programs to actually work with proper access, while using this option. Specifically, it introduces following changes: - may_access_direct_pkt_data: allow access to packet data based on the target prog - check_return_code: enforce return code based on the target prog (currently, this check is skipped for EXT program) - check_ld_abs: check for 'may_access_skb' based on the target prog - check_map_prog_compatibility: enforce the map compatibility check based on the target prog - may_update_sockmap: allow sockmap update based on the target prog Some other occurrences of prog->type is left as it without replacing with the 'resolved' type: - do_check_common() and check_attach_btf_id(): already have specific logic to handle the EXT prog type - jit_subprogs() and bpf_check(): Not changed for jit compilation or while inferring env->ops Next few patches in this series include selftests for some of these cases. Signed-off-by: Udip Pant <udippant@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200825232003.2877030-2-udippant@fb.com
2020-08-25bpf: Add BTF_SET_START/END macrosJiri Olsa
Adding support to define sorted set of BTF ID values. Following defines sorted set of BTF ID values: BTF_SET_START(btf_allowlist_d_path) BTF_ID(func, vfs_truncate) BTF_ID(func, vfs_fallocate) BTF_ID(func, dentry_open) BTF_ID(func, vfs_getattr) BTF_ID(func, filp_close) BTF_SET_END(btf_allowlist_d_path) It defines following 'struct btf_id_set' variable to access values and count: struct btf_id_set btf_allowlist_d_path; Adding 'allowed' callback to struct bpf_func_proto, to allow verifier the check on allowed callers. Adding btf_id_set_contains function, which will be used by allowed callbacks to verify the caller's BTF ID value is within allowed set. Also removing extra '\' in __BTF_ID_LIST macro. Added BTF_SET_START_GLOBAL macro for global sets. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200825192124.710397-10-jolsa@kernel.org
2020-08-25bpf: Add btf_struct_ids_match functionJiri Olsa
Adding btf_struct_ids_match function to check if given address provided by BTF object + offset is also address of another nested BTF object. This allows to pass an argument to helper, which is defined via parent BTF object + offset, like for bpf_d_path (added in following changes): SEC("fentry/filp_close") int BPF_PROG(prog_close, struct file *file, void *id) { ... ret = bpf_d_path(&file->f_path, ... The first bpf_d_path argument is hold by verifier as BTF file object plus offset of f_path member. The btf_struct_ids_match function will walk the struct file object and check if there's nested struct path object on the given offset. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200825192124.710397-9-jolsa@kernel.org
2020-08-25bpf: Factor btf_struct_access functionJiri Olsa
Adding btf_struct_walk function that walks through the struct type + given offset and returns following values: enum bpf_struct_walk_result { /* < 0 error */ WALK_SCALAR = 0, WALK_PTR, WALK_STRUCT, }; WALK_SCALAR - when SCALAR_VALUE is found WALK_PTR - when pointer value is found, its ID is stored in 'next_btf_id' output param WALK_STRUCT - when nested struct object is found, its ID is stored in 'next_btf_id' output param It will be used in following patches to get all nested struct objects for given type and offset. The btf_struct_access now calls btf_struct_walk function, as long as it gets nested structs as return value. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200825192124.710397-8-jolsa@kernel.org
2020-08-25bpf: Remove recursion call in btf_struct_accessJiri Olsa
Andrii suggested we can simply jump to again label instead of making recursion call. Suggested-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200825192124.710397-7-jolsa@kernel.org
2020-08-25bpf: Add type_id pointer as argument to __btf_resolve_sizeJiri Olsa
Adding type_id pointer as argument to __btf_resolve_size to return also BTF ID of the resolved type. It will be used in following changes. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200825192124.710397-6-jolsa@kernel.org
2020-08-25bpf: Add elem_id pointer as argument to __btf_resolve_sizeJiri Olsa
If the resolved type is array, make btf_resolve_size return also ID of the elem type. It will be needed in following changes. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200825192124.710397-5-jolsa@kernel.org
2020-08-25bpf: Move btf_resolve_size into __btf_resolve_sizeJiri Olsa
Moving btf_resolve_size into __btf_resolve_size and keeping btf_resolve_size public with just first 3 arguments, because the rest of the arguments are not used by outside callers. Following changes are adding more arguments, which are not useful to outside callers. They will be added to the __btf_resolve_size function. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200825192124.710397-4-jolsa@kernel.org
2020-08-25bpf: Disallow BPF_PRELOAD in allmodconfig buildsAlexei Starovoitov
The CC_CAN_LINK checks that the host compiler can link, but bpf_preload relies on libbpf which in turn needs libelf to be present during linking. allmodconfig runs in odd setups with cross compilers and missing host libraries like libelf. Instead of extending kconfig with every possible library that bpf_preload might need disallow building BPF_PRELOAD in such build-only configurations. Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-08-25bpf: Allow local storage to be used from LSM programsKP Singh
Adds support for both bpf_{sk, inode}_storage_{get, delete} to be used in LSM programs. These helpers are not used for tracing programs (currently) as their usage is tied to the life-cycle of the object and should only be used where the owning object won't be freed (when the owning object is passed as an argument to the LSM hook). Thus, they are safer to use in LSM hooks than tracing. Usage of local storage in tracing programs will probably follow a per function based whitelist approach. Since the UAPI helper signature for bpf_sk_storage expect a bpf_sock, it, leads to a compilation warning for LSM programs, it's also updated to accept a void * pointer instead. Signed-off-by: KP Singh <kpsingh@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20200825182919.1118197-7-kpsingh@chromium.org
2020-08-25bpf: Implement bpf_local_storage for inodesKP Singh
Similar to bpf_local_storage for sockets, add local storage for inodes. The life-cycle of storage is managed with the life-cycle of the inode. i.e. the storage is destroyed along with the owning inode. The BPF LSM allocates an __rcu pointer to the bpf_local_storage in the security blob which are now stackable and can co-exist with other LSMs. Signed-off-by: KP Singh <kpsingh@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200825182919.1118197-6-kpsingh@chromium.org
2020-08-25bpf: Split bpf_local_storage to bpf_sk_storageKP Singh
A purely mechanical change: bpf_sk_storage.c = bpf_sk_storage.c + bpf_local_storage.c bpf_sk_storage.h = bpf_sk_storage.h + bpf_local_storage.h Signed-off-by: KP Singh <kpsingh@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20200825182919.1118197-5-kpsingh@chromium.org
2020-08-24bpf: Fix a buffer out-of-bound access when filling raw_tp link_infoYonghong Song
Commit f2e10bff16a0 ("bpf: Add support for BPF_OBJ_GET_INFO_BY_FD for bpf_link") added link query for raw_tp. One of fields in link_info is to fill a user buffer with tp_name. The Scurrent checking only declares "ulen && !ubuf" as invalid. So "!ulen && ubuf" will be valid. Later on, we do "copy_to_user(ubuf, tp_name, ulen - 1)" which may overwrite user memory incorrectly. This patch fixed the problem by disallowing "!ulen && ubuf" case as well. Fixes: f2e10bff16a0 ("bpf: Add support for BPF_OBJ_GET_INFO_BY_FD for bpf_link") Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200821191054.714731-1-yhs@fb.com
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-21bpf: sockmap: Allow update from BPFLorenz Bauer
Allow calling bpf_map_update_elem on sockmap and sockhash from a BPF context. The synchronization required for this is a bit fiddly: we need to prevent the socket from changing its state while we add it to the sockmap, since we rely on getting a callback via sk_prot->unhash. However, we can't just lock_sock like in sock_map_sk_acquire because that might sleep. So instead we disable softirq processing and use bh_lock_sock to prevent further modification. Yet, this is still not enough. BPF can be called in contexts where the current CPU might have locked a socket. If the BPF can get a hold of such a socket, inserting it into a sockmap would lead to a deadlock. One straight forward example are sock_ops programs that have ctx->sk, but the same problem exists for kprobes, etc. We deal with this by allowing sockmap updates only from known safe contexts. Improper usage is rejected by the verifier. I've audited the enabled contexts to make sure they can't run in a locked context. It's possible that CGROUP_SKB and others are safe as well, but the auditing here is much more difficult. In any case, we can extend the safe contexts when the need arises. Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200821102948.21918-6-lmb@cloudflare.com
2020-08-21bpf: Override the meaning of ARG_PTR_TO_MAP_VALUE for sockmap and sockhashLorenz Bauer
The verifier assumes that map values are simple blobs of memory, and therefore treats ARG_PTR_TO_MAP_VALUE, etc. as such. However, there are map types where this isn't true. For example, sockmap and sockhash store sockets. In general this isn't a big problem: we can just write helpers that explicitly requests PTR_TO_SOCKET instead of ARG_PTR_TO_MAP_VALUE. The one exception are the standard map helpers like map_update_elem, map_lookup_elem, etc. Here it would be nice we could overload the function prototype for different kinds of maps. Unfortunately, this isn't entirely straight forward: We only know the type of the map once we have resolved meta->map_ptr in check_func_arg. This means we can't swap out the prototype in check_helper_call until we're half way through the function. Instead, modify check_func_arg to treat ARG_PTR_TO_MAP_VALUE to mean "the native type for the map" instead of "pointer to memory" for sockmap and sockhash. This means we don't have to modify the function prototype at all Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200821102948.21918-5-lmb@cloudflare.com
2020-08-21bpf: sockmap: Call sock_map_update_elem directlyLorenz Bauer
Don't go via map->ops to call sock_map_update_elem, since we know what function to call in bpf_map_update_value. Since we currently don't allow calling map_update_elem from BPF context, we can remove ops->map_update_elem and rename the function to sock_map_update_elem_sys. Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200821102948.21918-4-lmb@cloudflare.com
2020-08-21bpf: Implement link_query callbacks in map element iteratorsYonghong Song
For bpf_map_elem and bpf_sk_local_storage bpf iterators, additional map_id should be shown for fdinfo and userspace query. For example, the following is for a bpf_map_elem iterator. $ cat /proc/1753/fdinfo/9 pos: 0 flags: 02000000 mnt_id: 14 link_type: iter link_id: 34 prog_tag: 104be6d3fe45e6aa prog_id: 173 target_name: bpf_map_elem map_id: 127 Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200821184419.574240-1-yhs@fb.com
2020-08-21bpf: Implement link_query for bpf iteratorsYonghong Song
This patch implemented bpf_link callback functions show_fdinfo and fill_link_info to support link_query interface. The general interface for show_fdinfo and fill_link_info will print/fill the target_name. Each targets can register show_fdinfo and fill_link_info callbacks to print/fill more target specific information. For example, the below is a fdinfo result for a bpf task iterator. $ cat /proc/1749/fdinfo/7 pos: 0 flags: 02000000 mnt_id: 14 link_type: iter link_id: 11 prog_tag: 990e1f8152f7e54f prog_id: 59 target_name: task Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200821184418.574122-1-yhs@fb.com
2020-08-20bpf: Add kernel module with user mode driver that populates bpffs.Alexei Starovoitov
Add kernel module with user mode driver that populates bpffs with BPF iterators. $ mount bpffs /my/bpffs/ -t bpf $ ls -la /my/bpffs/ total 4 drwxrwxrwt 2 root root 0 Jul 2 00:27 . drwxr-xr-x 19 root root 4096 Jul 2 00:09 .. -rw------- 1 root root 0 Jul 2 00:27 maps.debug -rw------- 1 root root 0 Jul 2 00:27 progs.debug The user mode driver will load BPF Type Formats, create BPF maps, populate BPF maps, load two BPF programs, attach them to BPF iterators, and finally send two bpf_link IDs back to the kernel. The kernel will pin two bpf_links into newly mounted bpffs instance under names "progs.debug" and "maps.debug". These two files become human readable. $ cat /my/bpffs/progs.debug id name attached 11 dump_bpf_map bpf_iter_bpf_map 12 dump_bpf_prog bpf_iter_bpf_prog 27 test_pkt_access 32 test_main test_pkt_access test_pkt_access 33 test_subprog1 test_pkt_access_subprog1 test_pkt_access 34 test_subprog2 test_pkt_access_subprog2 test_pkt_access 35 test_subprog3 test_pkt_access_subprog3 test_pkt_access 36 new_get_skb_len get_skb_len test_pkt_access 37 new_get_skb_ifindex get_skb_ifindex test_pkt_access 38 new_get_constant get_constant test_pkt_access The BPF program dump_bpf_prog() in iterators.bpf.c is printing this data about all BPF programs currently loaded in the system. This information is unstable and will change from kernel to kernel as ".debug" suffix conveys. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200819042759.51280-4-alexei.starovoitov@gmail.com
2020-08-20bpf: Add BPF program and map iterators as built-in BPF programs.Alexei Starovoitov
The program and map iterators work similar to seq_file-s. Once the program is pinned in bpffs it can be read with "cat" tool to print human readable output. In this case about BPF programs and maps. For example: $ cat /sys/fs/bpf/progs.debug id name attached 5 dump_bpf_map bpf_iter_bpf_map 6 dump_bpf_prog bpf_iter_bpf_prog $ cat /sys/fs/bpf/maps.debug id name max_entries 3 iterator.rodata 1 To avoid kernel build dependency on clang 10 separate bpf skeleton generation into manual "make" step and instead check-in generated .skel.h into git. Unlike 'bpftool prog show' in-kernel BTF name is used (when available) to print full name of BPF program instead of 16-byte truncated name. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200819042759.51280-3-alexei.starovoitov@gmail.com
2020-08-20bpf: Factor out bpf_link_by_id() helper.Alexei Starovoitov
Refactor the code a bit to extract bpf_link_by_id() helper. It's similar to existing bpf_prog_by_id(). Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200819042759.51280-2-alexei.starovoitov@gmail.com
2020-08-18bpf: Avoid visit same object multiple timesYonghong Song
Currently when traversing all tasks, the next tid is always increased by one. This may result in visiting the same task multiple times in a pid namespace. This patch fixed the issue by seting the next tid as pid_nr_ns(pid, ns) + 1, similar to funciton next_tgid(). Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Rik van Riel <riel@surriel.com> Link: https://lore.kernel.org/bpf/20200818222310.2181500-1-yhs@fb.com
2020-08-18bpf: Fix a rcu_sched stall issue with bpf task/task_file iteratorYonghong Song
In our production system, we observed rcu stalls when 'bpftool prog` is running. rcu: INFO: rcu_sched self-detected stall on CPU rcu: \x097-....: (20999 ticks this GP) idle=302/1/0x4000000000000000 softirq=1508852/1508852 fqs=4913 \x09(t=21031 jiffies g=2534773 q=179750) NMI backtrace for cpu 7 CPU: 7 PID: 184195 Comm: bpftool Kdump: loaded Tainted: G W 5.8.0-00004-g68bfc7f8c1b4 #6 Hardware name: Quanta Twin Lakes MP/Twin Lakes Passive MP, BIOS F09_3A17 05/03/2019 Call Trace: <IRQ> dump_stack+0x57/0x70 nmi_cpu_backtrace.cold+0x14/0x53 ? lapic_can_unplug_cpu.cold+0x39/0x39 nmi_trigger_cpumask_backtrace+0xb7/0xc7 rcu_dump_cpu_stacks+0xa2/0xd0 rcu_sched_clock_irq.cold+0x1ff/0x3d9 ? tick_nohz_handler+0x100/0x100 update_process_times+0x5b/0x90 tick_sched_timer+0x5e/0xf0 __hrtimer_run_queues+0x12a/0x2a0 hrtimer_interrupt+0x10e/0x280 __sysvec_apic_timer_interrupt+0x51/0xe0 asm_call_on_stack+0xf/0x20 </IRQ> sysvec_apic_timer_interrupt+0x6f/0x80 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:task_file_seq_get_next+0x71/0x220 Code: 00 00 8b 53 1c 49 8b 7d 00 89 d6 48 8b 47 20 44 8b 18 41 39 d3 76 75 48 8b 4f 20 8b 01 39 d0 76 61 41 89 d1 49 39 c1 48 19 c0 <48> 8b 49 08 21 d0 48 8d 04 c1 4c 8b 08 4d 85 c9 74 46 49 8b 41 38 RSP: 0018:ffffc90006223e10 EFLAGS: 00000297 RAX: ffffffffffffffff RBX: ffff888f0d172388 RCX: ffff888c8c07c1c0 RDX: 00000000000f017b RSI: 00000000000f017b RDI: ffff888c254702c0 RBP: ffffc90006223e68 R08: ffff888be2a1c140 R09: 00000000000f017b R10: 0000000000000002 R11: 0000000000100000 R12: ffff888f23c24118 R13: ffffc90006223e60 R14: ffffffff828509a0 R15: 00000000ffffffff task_file_seq_next+0x52/0xa0 bpf_seq_read+0xb9/0x320 vfs_read+0x9d/0x180 ksys_read+0x5f/0xe0 do_syscall_64+0x38/0x60 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f8815f4f76e Code: c0 e9 f6 fe ff ff 55 48 8d 3d 76 70 0a 00 48 89 e5 e8 36 06 02 00 66 0f 1f 44 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 52 c3 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 RSP: 002b:00007fff8f9df578 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000000000170b9c0 RCX: 00007f8815f4f76e RDX: 0000000000001000 RSI: 00007fff8f9df5b0 RDI: 0000000000000007 RBP: 00007fff8f9e05f0 R08: 0000000000000049 R09: 0000000000000010 R10: 00007f881601fa40 R11: 0000000000000246 R12: 00007fff8f9e05a8 R13: 00007fff8f9e05a8 R14: 0000000001917f90 R15: 000000000000e22e Note that `bpftool prog` actually calls a task_file bpf iterator program to establish an association between prog/map/link/btf anon files and processes. In the case where the above rcu stall occured, we had a process having 1587 tasks and each task having roughly 81305 files. This implied 129 million bpf prog invocations. Unfortunwtely none of these files are prog/map/link/btf files so bpf iterator/prog needs to traverse all these files and not able to return to user space since there are no seq_file buffer overflow. This patch fixed the issue in bpf_seq_read() to limit the number of visited objects. If the maximum number of visited objects is reached, no more objects will be visited in the current syscall. If there is nothing written in the seq_file buffer, -EAGAIN will return to the user so user can try again. The maximum number of visited objects is set at 1 million. In our Intel Xeon D-2191 2.3GHZ 18-core server, bpf_seq_read() visiting 1 million files takes around 0.18 seconds. We did not use cond_resched() since for some iterators, e.g., netlink iterator, where rcu read_lock critical section spans between consecutive seq_ops->next(), which makes impossible to do cond_resched() in the key while loop of function bpf_seq_read(). Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/bpf/20200818222309.2181348-1-yhs@fb.com
2020-08-17bpf: Use get_file_rcu() instead of get_file() for task_file iteratorYonghong Song
With latest `bpftool prog` command, we observed the following kernel panic. BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD dfe894067 P4D dfe894067 PUD deb663067 PMD 0 Oops: 0010 [#1] SMP CPU: 9 PID: 6023 ... RIP: 0010:0x0 Code: Bad RIP value. RSP: 0000:ffffc900002b8f18 EFLAGS: 00010286 RAX: ffff8883a405f400 RBX: ffff888e46a6bf00 RCX: 000000008020000c RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8883a405f400 RBP: ffff888e46a6bf50 R08: 0000000000000000 R09: ffffffff81129600 R10: ffff8883a405f300 R11: 0000160000000000 R12: 0000000000002710 R13: 000000e9494b690c R14: 0000000000000202 R15: 0000000000000009 FS: 00007fd9187fe700(0000) GS:ffff888e46a40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000de5d33002 CR4: 0000000000360ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> rcu_core+0x1a4/0x440 __do_softirq+0xd3/0x2c8 irq_exit+0x9d/0xa0 smp_apic_timer_interrupt+0x68/0x120 apic_timer_interrupt+0xf/0x20 </IRQ> RIP: 0033:0x47ce80 Code: Bad RIP value. RSP: 002b:00007fd9187fba40 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000002 RBX: 00007fd931789160 RCX: 000000000000010c RDX: 00007fd9308cdfb4 RSI: 00007fd9308cdfb4 RDI: 00007ffedd1ea0a8 RBP: 00007fd9187fbab0 R08: 000000000000000e R09: 000000000000002a R10: 0000000000480210 R11: 00007fd9187fc570 R12: 00007fd9316cc400 R13: 0000000000000118 R14: 00007fd9308cdfb4 R15: 00007fd9317a9380 After further analysis, the bug is triggered by Commit eaaacd23910f ("bpf: Add task and task/file iterator targets") which introduced task_file bpf iterator, which traverses all open file descriptors for all tasks in the current namespace. The latest `bpftool prog` calls a task_file bpf program to traverse all files in the system in order to associate processes with progs/maps, etc. When traversing files for a given task, rcu read_lock is taken to access all files in a file_struct. But it used get_file() to grab a file, which is not right. It is possible file->f_count is 0 and get_file() will unconditionally increase it. Later put_file() may cause all kind of issues with the above as one of sympotoms. The failure can be reproduced with the following steps in a few seconds: $ cat t.c #include <stdio.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> #define N 10000 int fd[N]; int main() { int i; for (i = 0; i < N; i++) { fd[i] = open("./note.txt", 'r'); if (fd[i] < 0) { fprintf(stderr, "failed\n"); return -1; } } for (i = 0; i < N; i++) close(fd[i]); return 0; } $ gcc -O2 t.c $ cat run.sh #/bin/bash for i in {1..100} do while true; do ./a.out; done & done $ ./run.sh $ while true; do bpftool prog >& /dev/null; done This patch used get_file_rcu() which only grabs a file if the file->f_count is not zero. This is to ensure the file pointer is always valid. The above reproducer did not fail for more than 30 minutes. Fixes: eaaacd23910f ("bpf: Add task and task/file iterator targets") Suggested-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Link: https://lore.kernel.org/bpf/20200817174214.252601-1-yhs@fb.com
2020-08-12bpf: Iterate through all PT_NOTE sections when looking for build idJiri Olsa
Currently when we look for build id within bpf_get_stackid helper call, we check the first NOTE section and we fail if build id is not there. However on some system (Fedora) there can be multiple NOTE sections in binaries and build id data is not always the first one, like: $ readelf -a /usr/bin/ls ... [ 2] .note.gnu.propert NOTE 0000000000000338 00000338 0000000000000020 0000000000000000 A 0 0 8358 [ 3] .note.gnu.build-i NOTE 0000000000000358 00000358 0000000000000024 0000000000000000 A 0 0 437c [ 4] .note.ABI-tag NOTE 000000000000037c 0000037c ... So the stack_map_get_build_id function will fail on build id retrieval and fallback to BPF_STACK_BUILD_ID_IP. This patch is changing the stack_map_get_build_id code to iterate through all the NOTE sections and try to get build id data from each of them. When tracing on sched_switch tracepoint that does bpf_get_stackid helper call kernel build, I can see about 60% increase of successful build id retrieval. The rest seems fails on -EFAULT. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200812123102.20032-1-jolsa@kernel.org
2020-08-07bpf: Delete repeated words in commentsRandy Dunlap
Drop repeated words in kernel/bpf/: {has, the} Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200807033141.10437-1-rdunlap@infradead.org
2020-08-06bpf: Change uapi for bpf iterator map elementsYonghong Song
Commit a5cbe05a6673 ("bpf: Implement bpf iterator for map elements") added bpf iterator support for map elements. The map element bpf iterator requires info to identify a particular map. In the above commit, the attr->link_create.target_fd is used to carry map_fd and an enum bpf_iter_link_info is added to uapi to specify the target_fd actually representing a map_fd: enum bpf_iter_link_info { BPF_ITER_LINK_UNSPEC = 0, BPF_ITER_LINK_MAP_FD = 1, MAX_BPF_ITER_LINK_INFO, }; This is an extensible approach as we can grow enumerator for pid, cgroup_id, etc. and we can unionize target_fd for pid, cgroup_id, etc. But in the future, there are chances that more complex customization may happen, e.g., for tasks, it could be filtered based on both cgroup_id and user_id. This patch changed the uapi to have fields __aligned_u64 iter_info; __u32 iter_info_len; for additional iter_info for link_create. The iter_info is defined as union bpf_iter_link_info { struct { __u32 map_fd; } map; }; So future extension for additional customization will be easier. The bpf_iter_link_info will be passed to target callback to validate and generic bpf_iter framework does not need to deal it any more. Note that map_fd = 0 will be considered invalid and -EBADF will be returned to user space. Fixes: a5cbe05a6673 ("bpf: Implement bpf iterator for map elements") Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200805055056.1457463-1-yhs@fb.com
2020-08-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2020-08-04 The following pull-request contains BPF updates for your *net-next* tree. We've added 73 non-merge commits during the last 9 day(s) which contain a total of 135 files changed, 4603 insertions(+), 1013 deletions(-). The main changes are: 1) Implement bpf_link support for XDP. Also add LINK_DETACH operation for the BPF syscall allowing processes with BPF link FD to force-detach, from Andrii Nakryiko. 2) Add BPF iterator for map elements and to iterate all BPF programs for efficient in-kernel inspection, from Yonghong Song and Alexei Starovoitov. 3) Separate bpf_get_{stack,stackid}() helpers for perf events in BPF to avoid unwinder errors, from Song Liu. 4) Allow cgroup local storage map to be shared between programs on the same cgroup. Also extend BPF selftests with coverage, from YiFei Zhu. 5) Add BPF exception tables to ARM64 JIT in order to be able to JIT BPF_PROBE_MEM load instructions, from Jean-Philippe Brucker. 6) Follow-up fixes on BPF socket lookup in combination with reuseport group handling. Also add related BPF selftests, from Jakub Sitnicki. 7) Allow to use socket storage in BPF_PROG_TYPE_CGROUP_SOCK-typed programs for socket create/release as well as bind functions, from Stanislav Fomichev. 8) Fix an info leak in xsk_getsockopt() when retrieving XDP stats via old struct xdp_statistics, from Peilin Ye. 9) Fix PT_REGS_RC{,_CORE}() macros in libbpf for MIPS arch, from Jerry Crunchtime. 10) Extend BPF kernel test infra with skb->family and skb->{local,remote}_ip{4,6} fields and allow user space to specify skb->dev via ifindex, from Dmitry Yakunin. 11) Fix a bpftool segfault due to missing program type name and make it more robust to prevent them in future gaps, from Quentin Monnet. 12) Consolidate cgroup helper functions across selftests and fix a v6 localhost resolver issue, from John Fastabend. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Resolved kernel/bpf/btf.c using instructions from merge commit 69138b34a7248d2396ab85c8652e20c0c39beaba Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-01bpf: Add support for forced LINK_DETACH commandAndrii Nakryiko
Add LINK_DETACH command to force-detach bpf_link without destroying it. It has the same behavior as auto-detaching of bpf_link due to cgroup dying for bpf_cgroup_link or net_device being destroyed for bpf_xdp_link. In such case, bpf_link is still a valid kernel object, but is defuncts and doesn't hold BPF program attached to corresponding BPF hook. This functionality allows users with enough access rights to manually force-detach attached bpf_link without killing respective owner process. This patch implements LINK_DETACH for cgroup, xdp, and netns links, mostly re-using existing link release handling code. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200731182830.286260-2-andriin@fb.com
2020-07-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2020-07-31 The following pull-request contains BPF updates for your *net* tre