- 29 4月, 2020 25 次提交
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由 Andrii Nakryiko 提交于
getline() allocates string, which has to be freed. Fixes: 81f77fd0 ("bpf: add selftest for stackmap with BPF_F_STACK_BUILD_ID") Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200429012111.277390-7-andriin@fb.com
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由 Andrii Nakryiko 提交于
Free test selector substrings, which were strdup()'ed. Fixes: b65053cd ("selftests/bpf: Add whitelist/blacklist of test names to test_progs") Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429012111.277390-6-andriin@fb.com
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由 Andrii Nakryiko 提交于
Fix memory leak in hashmap_clear() not freeing hashmap_entry structs for each of the remaining entries. Also NULL-out bucket list to prevent possible double-free between hashmap__clear() and hashmap__free(). Running test_progs-asan flavor clearly showed this problem. Reported-by: NAlston Tang <alston64@fb.com> Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429012111.277390-5-andriin@fb.com
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由 Andrii Nakryiko 提交于
Fold stand-alone test_hashmap test into test_progs. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429012111.277390-4-andriin@fb.com
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由 Andrii Nakryiko 提交于
Add ability to specify extra compiler flags with SAN_CFLAGS for compilation of all user-space C files. This allows to build all of selftest programs with, e.g., custom sanitizer flags, without requiring support for such sanitizers from anyone compiling selftest/bpf. As an example, to compile everything with AddressSanitizer, one would do: $ make clean && make SAN_CFLAGS="-fsanitize=address" For AddressSanitizer to work, one needs appropriate libasan shared library installed in the system, with version of libasan matching what GCC links against. E.g., GCC8 needs libasan5, while GCC7 uses libasan4. For CentOS 7, to build everything successfully one would need to: $ sudo yum install devtoolset-8-gcc devtoolset-libasan-devel $ scl enable devtoolset-8 bash # set up environment For Arch Linux to run selftests, one would need to install gcc-libs package to get libasan.so.5: $ sudo pacman -S gcc-libs N.B. EXTRA_CFLAGS name wasn't used, because it's also used by libbpf's Makefile and this causes few issues: 1. default "-g -Wall" flags are overriden; 2. compiling shared library with AddressSanitizer generates a bunch of symbols like: "_GLOBAL__sub_D_00099_0_btf_dump.c", "_GLOBAL__sub_D_00099_0_bpf.c", etc, which screws up versioned symbols check. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Cc: Julia Kartseva <hex@fb.com> Link: https://lore.kernel.org/bpf/20200429012111.277390-3-andriin@fb.com
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由 Andrii Nakryiko 提交于
Ensure that test runner flavors include their own skeletons from <flavor>/ directory. Previously, skeletons generated for no-flavor test_progs were used. Apart from fixing correctness, this also makes it possible to compile only flavors individually: $ make clean && make test_progs-no_alu32 ... now succeeds ... Fixes: 74b5a596 ("selftests/bpf: Replace test_progs and test_maps w/ general rule") Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429012111.277390-2-andriin@fb.com
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由 Alexei Starovoitov 提交于
Andrii Nakryiko says: ==================== This patch set teaches libbpf how to declare and initialize ARRAY_OF_MAPS and HASH_OF_MAPS maps. See patch #3 for all the details. Patch #1 refactors parsing BTF definition of map to re-use it cleanly for inner map definition parsing. Patch #2 refactors map creation and destruction logic for reuse. It also fixes existing bug with not closing successfully created maps when bpf_object map creation overall fails. Patch #3 adds support for an extension of BTF-defined map syntax, as well as parsing, recording, and use of relocations to allow declaratively initialize outer maps with references to inner maps. v1->v2: - rename __inner to __array (Alexei). ==================== Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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由 Andrii Nakryiko 提交于
As discussed at LPC 2019 ([0]), this patch brings (a quite belated) support for declarative BTF-defined map-in-map support in libbpf. It allows to define ARRAY_OF_MAPS and HASH_OF_MAPS BPF maps without any user-space initialization code involved. Additionally, it allows to initialize outer map's slots with references to respective inner maps at load time, also completely declaratively. Despite a weak type system of C, the way BTF-defined map-in-map definition works, it's actually quite hard to accidentally initialize outer map with incompatible inner maps. This being C, of course, it's still possible, but even that would be caught at load time and error returned with helpful debug log pointing exactly to the slot that failed to be initialized. As an example, here's a rather advanced HASH_OF_MAPS declaration and initialization example, filling slots #0 and #4 with two inner maps: #include <bpf/bpf_helpers.h> struct inner_map { __uint(type, BPF_MAP_TYPE_ARRAY); __uint(max_entries, 1); __type(key, int); __type(value, int); } inner_map1 SEC(".maps"), inner_map2 SEC(".maps"); struct outer_hash { __uint(type, BPF_MAP_TYPE_HASH_OF_MAPS); __uint(max_entries, 5); __uint(key_size, sizeof(int)); __array(values, struct inner_map); } outer_hash SEC(".maps") = { .values = { [0] = &inner_map2, [4] = &inner_map1, }, }; Here's the relevant part of libbpf debug log showing pretty clearly of what's going on with map-in-map initialization: libbpf: .maps relo #0: for 6 value 0 rel.r_offset 96 name 260 ('inner_map1') libbpf: .maps relo #0: map 'outer_arr' slot [0] points to map 'inner_map1' libbpf: .maps relo #1: for 7 value 32 rel.r_offset 112 name 249 ('inner_map2') libbpf: .maps relo #1: map 'outer_arr' slot [2] points to map 'inner_map2' libbpf: .maps relo #2: for 7 value 32 rel.r_offset 144 name 249 ('inner_map2') libbpf: .maps relo #2: map 'outer_hash' slot [0] points to map 'inner_map2' libbpf: .maps relo #3: for 6 value 0 rel.r_offset 176 name 260 ('inner_map1') libbpf: .maps relo #3: map 'outer_hash' slot [4] points to map 'inner_map1' libbpf: map 'inner_map1': created successfully, fd=4 libbpf: map 'inner_map2': created successfully, fd=5 libbpf: map 'outer_hash': created successfully, fd=7 libbpf: map 'outer_hash': slot [0] set to map 'inner_map2' fd=5 libbpf: map 'outer_hash': slot [4] set to map 'inner_map1' fd=4 Notice from the log above that fd=6 (not logged explicitly) is used for inner "prototype" map, necessary for creation of outer map. It is destroyed immediately after outer map is created. See also included selftest with some extra comments explaining extra details of usage. Additionally, similar initialization syntax and libbpf functionality can be used to do initialization of BPF_PROG_ARRAY with references to BPF sub-programs. This can be done in follow up patches, if there will be a demand for this. [0] https://linuxplumbersconf.org/event/4/contributions/448/Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Acked-by: NToke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200429002739.48006-4-andriin@fb.com
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由 Andrii Nakryiko 提交于
Factor out map creation and destruction logic to simplify code and especially error handling. Also fix map FD leak in case of partially successful map creation during bpf_object load operation. Fixes: 57a00f41 ("libbpf: Add auto-pinning of maps when loading BPF objects") Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Acked-by: NToke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200429002739.48006-3-andriin@fb.com
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由 Andrii Nakryiko 提交于
Factor out BTF map definition logic into stand-alone routine for easier reuse for map-in-map case. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429002739.48006-2-andriin@fb.com
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由 Alexei Starovoitov 提交于
Andrii Nakryiko says: ==================== This patch series adds various observability APIs to bpf_link: - each bpf_link now gets ID, similar to bpf_map and bpf_prog, by which user-space can iterate over all existing bpf_links and create limited FD from ID; - allows to get extra object information with bpf_link general and type-specific information; - implements `bpf link show` command which lists all active bpf_links in the system; - implements `bpf link pin` allowing to pin bpf_link by ID or from other pinned path. v2->v3: - improve spin locking around bpf_link ID (Alexei); - simplify bpf_link_info handling and fix compilation error on sh arch; v1->v2: - simplified `bpftool link show` implementation (Quentin); - fixed formatting of bpftool-link.rst (Quentin); - fixed attach type printing logic (Quentin); rfc->v1: - dropped read-only bpf_links (Alexei); - fixed bug in bpf_link_cleanup() not removing ID; - fixed bpftool link pinning search logic; - added bash-completion and man page. ==================== Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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由 Andrii Nakryiko 提交于
Extend bpftool's bash-completion script to handle new link command and its sub-commands. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Reviewed-by: NQuentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200429001614.1544-11-andriin@fb.com
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由 Andrii Nakryiko 提交于
Add bpftool-link manpage with information and examples of link-related commands. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Reviewed-by: NQuentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200429001614.1544-10-andriin@fb.com
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由 Andrii Nakryiko 提交于
Add `bpftool link show` and `bpftool link pin` commands. Example plain output for `link show` (with showing pinned paths): [vmuser@archvm bpf]$ sudo ~/local/linux/tools/bpf/bpftool/bpftool -f link 1: tracing prog 12 prog_type tracing attach_type fentry pinned /sys/fs/bpf/my_test_link pinned /sys/fs/bpf/my_test_link2 2: tracing prog 13 prog_type tracing attach_type fentry 3: tracing prog 14 prog_type tracing attach_type fentry 4: tracing prog 15 prog_type tracing attach_type fentry 5: tracing prog 16 prog_type tracing attach_type fentry 6: tracing prog 17 prog_type tracing attach_type fentry 7: raw_tracepoint prog 21 tp 'sys_enter' 8: cgroup prog 25 cgroup_id 584 attach_type egress 9: cgroup prog 25 cgroup_id 599 attach_type egress 10: cgroup prog 25 cgroup_id 614 attach_type egress 11: cgroup prog 25 cgroup_id 629 attach_type egress Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Reviewed-by: NQuentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200429001614.1544-9-andriin@fb.com
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由 Andrii Nakryiko 提交于
Move attach_type_strings into main.h for access in non-cgroup code. bpf_attach_type is used for non-cgroup attach types quite widely now. So also complete missing string translations for non-cgroup attach types. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Reviewed-by: NQuentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200429001614.1544-8-andriin@fb.com
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由 Andrii Nakryiko 提交于
Extend bpf_obj_id selftest to verify bpf_link's observability APIs. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429001614.1544-7-andriin@fb.com
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由 Andrii Nakryiko 提交于
Add low-level API calls for bpf_link_get_next_id() and bpf_link_get_fd_by_id(). Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429001614.1544-6-andriin@fb.com
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由 Andrii Nakryiko 提交于
Add ability to fetch bpf_link details through BPF_OBJ_GET_INFO_BY_FD command. Also enhance show_fdinfo to potentially include bpf_link type-specific information (similarly to obj_info). Also introduce enum bpf_link_type stored in bpf_link itself and expose it in UAPI. bpf_link_tracing also now will store and return bpf_attach_type. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429001614.1544-5-andriin@fb.com
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由 Andrii Nakryiko 提交于
Add support to look up bpf_link by ID and iterate over all existing bpf_links in the system. GET_FD_BY_ID code handles not-yet-ready bpf_link by checking that its ID hasn't been set to non-zero value yet. Setting bpf_link's ID is done as the very last step in finalizing bpf_link, together with installing FD. This approach allows users of bpf_link in kernel code to not worry about races between user-space and kernel code that hasn't finished attaching and initializing bpf_link. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429001614.1544-4-andriin@fb.com
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由 Andrii Nakryiko 提交于
Generate ID for each bpf_link using IDR, similarly to bpf_map and bpf_prog. bpf_link creation, initialization, attachment, and exposing to user-space through FD and ID is a complicated multi-step process, abstract it away through bpf_link_primer and bpf_link_prime(), bpf_link_settle(), and bpf_link_cleanup() internal API. They guarantee that until bpf_link is properly attached, user-space won't be able to access partially-initialized bpf_link either from FD or ID. All this allows to simplify bpf_link attachment and error handling code. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429001614.1544-3-andriin@fb.com
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由 Andrii Nakryiko 提交于
Make bpf_link update support more generic by making it into another bpf_link_ops methods. This allows generic syscall handling code to be agnostic to various conditionally compiled features (e.g., the case of CONFIG_CGROUP_BPF). This also allows to keep link type-specific code to remain static within respective code base. Refactor existing bpf_cgroup_link code and take advantage of this. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429001614.1544-2-andriin@fb.com
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由 Alexei Starovoitov 提交于
Similar to commit b7a0d65d ("bpf, testing: Workaround a verifier failure for test_progs") fix test_sysctl_prog.c as well. Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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由 Zou Wei 提交于
Fixes the following coccicheck warning: tools/lib/bpf/btf_dump.c:661:4-5: Unneeded semicolon Reported-by: NHulk Robot <hulkci@huawei.com> Signed-off-by: NZou Wei <zou_wei@huawei.com> Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/1588064829-70613-1-git-send-email-zou_wei@huawei.com
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由 Veronika Kabatova 提交于
$(OUTPUT)/runqslower makefile target doesn't actually create runqslower binary in the $(OUTPUT) directory. As lib.mk expects all TEST_GEN_PROGS_EXTENDED (which runqslower is a part of) to be present in the OUTPUT directory, this results in an error when running e.g. `make install`: rsync: link_stat "tools/testing/selftests/bpf/runqslower" failed: No such file or directory (2) Copy the binary into the OUTPUT directory after building it to fix the error. Fixes: 3a0d3092 ("selftests/bpf: Build runqslower from selftests") Signed-off-by: NVeronika Kabatova <vkabatov@redhat.com> Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Acked-by: NAndrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200428173742.2988395-1-vkabatov@redhat.com
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ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/viro/vfs由 Daniel Borkmann 提交于
Pull in Christoph Hellwig's series that changes the sysctl's ->proc_handler methods to take kernel pointers instead. It gets rid of the set_fs address space overrides used by BPF. As per discussion, pull in the feature branch into bpf-next as it relates to BPF sysctl progs. Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200427071508.GV23230@ZenIV.linux.org.uk/T/
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- 28 4月, 2020 1 次提交
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由 Christoph Hellwig 提交于
Except for a few of the networking hooks called from modular ipv4 or ipv6 code, all of hooks are just called from guaranteed to be built-in code. Signed-off-by: NChristoph Hellwig <hch@lst.de> Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Acked-by: NAndrey Ignatov <rdna@fb.com> Link: https://lore.kernel.org/bpf/20200424064338.538313-2-hch@lst.de
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- 27 4月, 2020 12 次提交
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由 Mao Wenan 提交于
bpf_object__load() has various return code, when it failed to load object, it must return err instead of -EINVAL. Signed-off-by: NMao Wenan <maowenan@huawei.com> Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Acked-by: NAndrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200426063635.130680-3-maowenan@huawei.com
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由 Christoph Hellwig 提交于
Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NAndrey Ignatov <rdna@fb.com> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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由 Christoph Hellwig 提交于
Move the sysctl tables to the end of the file to avoid lots of pointless forward declarations. Signed-off-by: NChristoph Hellwig <hch@lst.de> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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由 Christoph Hellwig 提交于
Extern declarations in .c files are a bad style and can lead to mismatches. Use existing definitions in headers where they exist, and otherwise move the external declarations to suitable header files. Signed-off-by: NChristoph Hellwig <hch@lst.de> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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由 Christoph Hellwig 提交于
watermark_boost_factor_sysctl_handler is just a pointless wrapper for proc_dointvec_minmax, so remove it and use proc_dointvec_minmax directly. Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NDavid Rientjes <rientjes@google.com> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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由 Alexei Starovoitov 提交于
Lorenz Bauer says: ==================== We've been developing an in-house L4 load balancer based on XDP and TC for a while. Following Alexei's call for more up-to-date examples of production BPF in the kernel tree [1], Cloudflare is making this available under dual GPL-2.0 or BSD 3-clause terms. The code requires at least v5.3 to function correctly. 1: https://lore.kernel.org/bpf/20200326210719.den5isqxntnoqhmv@ast-mbp/ ==================== Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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由 Lorenz Bauer 提交于
cls_redirect is a TC clsact based replacement for the glb-redirect iptables module available at [1]. It enables what GitHub calls "second chance" flows [2], similarly proposed by the Beamer paper [3]. In contrast to glb-redirect, it also supports migrating UDP flows as long as connected sockets are used. cls_redirect is in production at Cloudflare, as part of our own L4 load balancer. We have modified the encapsulation format slightly from glb-redirect: glbgue_chained_routing.private_data_type has been repurposed to form a version field and several flags. Both have been arranged in a way that a private_data_type value of zero matches the current glb-redirect behaviour. This means that cls_redirect will understand packets in glb-redirect format, but not vice versa. The test suite only covers basic features. For example, cls_redirect will correctly forward path MTU discovery packets, but this is not exercised. It is also possible to switch the encapsulation format to GRE on the last hop, which is also not tested. There are two major distinctions from glb-redirect: first, cls_redirect relies on receiving encapsulated packets directly from a router. This is because we don't have access to the neighbour tables from BPF, yet. See forward_to_next_hop for details. Second, cls_redirect performs decapsulation instead of using separate ipip and sit tunnel devices. This avoids issues with the sit tunnel [4] and makes deploying the classifier easier: decapsulated packets appear on the same interface, so existing firewall rules continue to work as expected. The code base started it's life on v4.19, so there are most likely still hold overs from old workarounds. In no particular order: - The function buf_off is required to defeat a clang optimization that leads to the verifier rejecting the program due to pointer arithmetic in the wrong order. - The function pkt_parse_ipv6 is force inlined, because it would otherwise be rejected due to returning a pointer to stack memory. - The functions fill_tuple and classify_tcp contain kludges, because we've run out of function arguments. - The logic in general is rather nested, due to verifier restrictions. I think this is either because the verifier loses track of constants on the stack, or because it can't track enum like variables. 1: https://github.com/github/glb-director/tree/master/src/glb-redirect 2: https://github.com/github/glb-director/blob/master/docs/development/second-chance-design.md 3: https://www.usenix.org/conference/nsdi18/presentation/olteanu 4: https://github.com/github/glb-director/issues/64Signed-off-by: NLorenz Bauer <lmb@cloudflare.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200424185556.7358-2-lmb@cloudflare.com
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由 Andrii Nakryiko 提交于
To make BPF verifier verbose log more releavant and easier to use to debug verification failures, "pop" parts of log that were successfully verified. This has effect of leaving only verifier logs that correspond to code branches that lead to verification failure, which in practice should result in much shorter and more relevant verifier log dumps. This behavior is made the default behavior and can be overriden to do exhaustive logging by specifying BPF_LOG_LEVEL2 log level. Using BPF_LOG_LEVEL2 to disable this behavior is not ideal, because in some cases it's good to have BPF_LOG_LEVEL2 per-instruction register dump verbosity, but still have only relevant verifier branches logged. But for this patch, I didn't want to add any new flags. It might be worth-while to just rethink how BPF verifier logging is performed and requested and streamline it a bit. But this trimming of successfully verified branches seems to be useful and a good default behavior. To test this, I modified runqslower slightly to introduce read of uninitialized stack variable. Log (**truncated in the middle** to save many lines out of this commit message) BEFORE this change: ; int handle__sched_switch(u64 *ctx) 0: (bf) r6 = r1 ; struct task_struct *prev = (struct task_struct *)ctx[1]; 1: (79) r1 = *(u64 *)(r6 +8) func 'sched_switch' arg1 has btf_id 151 type STRUCT 'task_struct' 2: (b7) r2 = 0 ; struct event event = {}; 3: (7b) *(u64 *)(r10 -24) = r2 last_idx 3 first_idx 0 regs=4 stack=0 before 2: (b7) r2 = 0 4: (7b) *(u64 *)(r10 -32) = r2 5: (7b) *(u64 *)(r10 -40) = r2 6: (7b) *(u64 *)(r10 -48) = r2 ; if (prev->state == TASK_RUNNING) [ ... instruction dump from insn #7 through #50 are cut out ... ] 51: (b7) r2 = 16 52: (85) call bpf_get_current_comm#16 last_idx 52 first_idx 42 regs=4 stack=0 before 51: (b7) r2 = 16 ; bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, 53: (bf) r1 = r6 54: (18) r2 = 0xffff8881f3868800 56: (18) r3 = 0xffffffff 58: (bf) r4 = r7 59: (b7) r5 = 32 60: (85) call bpf_perf_event_output#25 last_idx 60 first_idx 53 regs=20 stack=0 before 59: (b7) r5 = 32 61: (bf) r2 = r10 ; event.pid = pid; 62: (07) r2 += -16 ; bpf_map_delete_elem(&start, &pid); 63: (18) r1 = 0xffff8881f3868000 65: (85) call bpf_map_delete_elem#3 ; } 66: (b7) r0 = 0 67: (95) exit from 44 to 66: safe from 34 to 66: safe from 11 to 28: R1_w=inv0 R2_w=inv0 R6_w=ctx(id=0,off=0,imm=0) R10=fp0 fp-8=mmmm???? fp-24_w=00000000 fp-32_w=00000000 fp-40_w=00000000 fp-48_w=00000000 ; bpf_map_update_elem(&start, &pid, &ts, 0); 28: (bf) r2 = r10 ; 29: (07) r2 += -16 ; tsp = bpf_map_lookup_elem(&start, &pid); 30: (18) r1 = 0xffff8881f3868000 32: (85) call bpf_map_lookup_elem#1 invalid indirect read from stack off -16+0 size 4 processed 65 insns (limit 1000000) max_states_per_insn 1 total_states 5 peak_states 5 mark_read 4 Notice how there is a successful code path from instruction 0 through 67, few successfully verified jumps (44->66, 34->66), and only after that 11->28 jump plus error on instruction #32. AFTER this change (full verifier log, **no truncation**): ; int handle__sched_switch(u64 *ctx) 0: (bf) r6 = r1 ; struct task_struct *prev = (struct task_struct *)ctx[1]; 1: (79) r1 = *(u64 *)(r6 +8) func 'sched_switch' arg1 has btf_id 151 type STRUCT 'task_struct' 2: (b7) r2 = 0 ; struct event event = {}; 3: (7b) *(u64 *)(r10 -24) = r2 last_idx 3 first_idx 0 regs=4 stack=0 before 2: (b7) r2 = 0 4: (7b) *(u64 *)(r10 -32) = r2 5: (7b) *(u64 *)(r10 -40) = r2 6: (7b) *(u64 *)(r10 -48) = r2 ; if (prev->state == TASK_RUNNING) 7: (79) r2 = *(u64 *)(r1 +16) ; if (prev->state == TASK_RUNNING) 8: (55) if r2 != 0x0 goto pc+19 R1_w=ptr_task_struct(id=0,off=0,imm=0) R2_w=inv0 R6_w=ctx(id=0,off=0,imm=0) R10=fp0 fp-24_w=00000000 fp-32_w=00000000 fp-40_w=00000000 fp-48_w=00000000 ; trace_enqueue(prev->tgid, prev->pid); 9: (61) r1 = *(u32 *)(r1 +1184) 10: (63) *(u32 *)(r10 -4) = r1 ; if (!pid || (targ_pid && targ_pid != pid)) 11: (15) if r1 == 0x0 goto pc+16 from 11 to 28: R1_w=inv0 R2_w=inv0 R6_w=ctx(id=0,off=0,imm=0) R10=fp0 fp-8=mmmm???? fp-24_w=00000000 fp-32_w=00000000 fp-40_w=00000000 fp-48_w=00000000 ; bpf_map_update_elem(&start, &pid, &ts, 0); 28: (bf) r2 = r10 ; 29: (07) r2 += -16 ; tsp = bpf_map_lookup_elem(&start, &pid); 30: (18) r1 = 0xffff8881db3ce800 32: (85) call bpf_map_lookup_elem#1 invalid indirect read from stack off -16+0 size 4 processed 65 insns (limit 1000000) max_states_per_insn 1 total_states 5 peak_states 5 mark_read 4 Notice how in this case, there are 0-11 instructions + jump from 11 to 28 is recorded + 28-32 instructions with error on insn #32. test_verifier test runner was updated to specify BPF_LOG_LEVEL2 for VERBOSE_ACCEPT expected result due to potentially "incomplete" success verbose log at BPF_LOG_LEVEL1. On success, verbose log will only have a summary of number of processed instructions, etc, but no branch tracing log. Having just a last succesful branch tracing seemed weird and confusing. Having small and clean summary log in success case seems quite logical and nice, though. Signed-off-by: NAndrii Nakryiko <andriin@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200423195850.1259827-1-andriin@fb.com
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由 Maciej Żenczykowski 提交于
On a device like a cellphone which is constantly suspending and resuming CLOCK_MONOTONIC is not particularly useful for keeping track of or reacting to external network events. Instead you want to use CLOCK_BOOTTIME. Hence add bpf_ktime_get_boot_ns() as a mirror of bpf_ktime_get_ns() based around CLOCK_BOOTTIME instead of CLOCK_MONOTONIC. Signed-off-by: NMaciej Żenczykowski <maze@google.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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由 Tobias Klauser 提交于
s/backpreassure/backpressure/ Signed-off-by: NTobias Klauser <tklauser@distanz.ch> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Acked-by: NMagnus Karlsson <magnus.karlsson@intel.com> Link: https://lore.kernel.org/bpf/20200421232927.21082-1-tklauser@distanz.ch
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由 Maciej Żenczykowski 提交于
The entire implementation is in kernel/bpf/helpers.c: BPF_CALL_0(bpf_ktime_get_ns) { /* NMI safe access to clock monotonic */ return ktime_get_mono_fast_ns(); } const struct bpf_func_proto bpf_ktime_get_ns_proto = { .func = bpf_ktime_get_ns, .gpl_only = false, .ret_type = RET_INTEGER, }; and this was presumably marked GPL due to kernel/time/timekeeping.c: EXPORT_SYMBOL_GPL(ktime_get_mono_fast_ns); and while that may make sense for kernel modules (although even that is doubtful), there is currently AFAICT no other source of time available to ebpf. Furthermore this is really just equivalent to clock_gettime(CLOCK_MONOTONIC) which is exposed to userspace (via vdso even to make it performant)... As such, I see no reason to keep the GPL restriction. (In the future I'd like to have access to time from Apache licensed ebpf code) Signed-off-by: NMaciej Żenczykowski <maze@google.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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由 Lorenzo Colitti 提交于
This allows TC eBPF programs to modify and forward (redirect) packets from interfaces without ethernet headers (for example cellular) to interfaces with (for example ethernet/wifi). The lack of this appears to simply be an oversight. Tested: in active use in Android R on 4.14+ devices for ipv6 cellular to wifi tethering offload. Signed-off-by: NLorenzo Colitti <lorenzo@google.com> Signed-off-by: NMaciej Żenczykowski <maze@google.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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- 26 4月, 2020 2 次提交
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由 Stanislav Fomichev 提交于
linux-next build bot reported compile issue [1] with one of its configs. It looks like when we have CONFIG_NET=n and CONFIG_BPF{,_SYSCALL}=y, we are missing the bpf_base_func_proto definition (from net/core/filter.c) in cgroup_base_func_proto. I'm reshuffling the code a bit to make it work. The common helpers are moved into kernel/bpf/helpers.c and the bpf_base_func_proto is exported from there. Also, bpf_get_raw_cpu_id goes into kernel/bpf/core.c akin to existing bpf_user_rnd_u32. [1] https://lore.kernel.org/linux-next/CAKH8qBsBvKHswiX1nx40LgO+BGeTmb1NX8tiTttt_0uu6T3dCA@mail.gmail.com/T/#mff8b0c083314c68c2e2ef0211cb11bc20dc13c72 Fixes: 0456ea17 ("bpf: Enable more helpers for BPF_PROG_TYPE_CGROUP_{DEVICE,SYSCTL,SOCKOPT}") Signed-off-by: NStanislav Fomichev <sdf@google.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200424235941.58382-1-sdf@google.com
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由 Luke Nelson 提交于
This patch fixes an off by one error in the RV32 JIT handling for BPF tail call. Currently, the code decrements TCC before checking if it is less than zero. This limits the maximum number of tail calls to 32 instead of 33 as in other JITs. The fix is to instead check the old value of TCC before decrementing. Fixes: 5f316b65 ("riscv, bpf: Add RV32G eBPF JIT") Signed-off-by: NLuke Nelson <luke.r.nels@gmail.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Acked-by: NXi Wang <xi.wang@gmail.com> Link: https://lore.kernel.org/bpf/20200421002804.5118-1-luke.r.nels@gmail.com
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