kernel/linux.git/samples/bpf, branch v5.5.10

samples/bpf: Set -fno-stack-protector when building BPF programs

2020-02-24T07:38:15+00:00

[ Upstream commit 450278977acbf494a20367c22fbb38729772d1fc ] It seems Clang can in some cases turn on stack protection by default, which doesn't work with BPF. This was reported once before[0], but it seems the flag to explicitly turn off the stack protector wasn't added to the Makefile, so do that now. The symptom of this is compile errors like the following: error: :0:0: in function bpf_prog1 i32 (%struct.__sk_buff*): A call to built-in function '__stack_chk_fail' is not supported. [0] https://www.spinics.net/lists/netdev/msg556400.html Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191216103819.359535-1-toke@redhat.com Signed-off-by: Sasha Levin

samples/bpf: Reintroduce missed build targets

2020-02-11T12:37:00+00:00

commit 5984dc6cb5aa6cce342a44f01f984fde09ed05b1 upstream. Add xdp_redirect and per_socket_stats_example in build targets. They got removed from build targets in Makefile reorganization. Fixes: 1d97c6c2511f ("samples/bpf: Base target programs rules on Makefile.target") Signed-off-by: Prashant Bhole Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191216071619.25479-1-prashantbhole.linux@gmail.com Signed-off-by: Greg Kroah-Hartman

samples/bpf: Xdp_redirect_cpu fix missing tracepoint attach

2020-02-11T12:36:59+00:00

commit f9e6bfdbaf0cf304d72c70a05d81acac01a04f48 upstream. When sample xdp_redirect_cpu was converted to use libbpf, the tracepoints used by this sample were not getting attached automatically like with bpf_load.c. The BPF-maps was still getting loaded, thus nobody notice that the tracepoints were not updating these maps. This fix doesn't use the new skeleton code, as this bug was introduced in v5.1 and stable might want to backport this. E.g. Red Hat QA uses this sample as part of their testing. Fixes: bbaf6029c49c ("samples/bpf: Convert XDP samples to libbpf usage") Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/157685877642.26195.2798780195186786841.stgit@firesoul Signed-off-by: Greg Kroah-Hartman

samples/bpf: Don't try to remove user's homedir on clean

2020-02-11T12:36:59+00:00

commit b2e5e93ae8af6a34bca536cdc4b453ab1e707b8b upstream. The 'clean' rule in the samples/bpf Makefile tries to remove backup files (ending in ~). However, if no such files exist, it will instead try to remove the user's home directory. While the attempt is mostly harmless, it does lead to a somewhat scary warning like this: rm: cannot remove '~': Is a directory Fix this by using find instead of shell expansion to locate any actual backup files that need to be removed. Fixes: b62a796c109c ("samples/bpf: allow make to be run from samples/bpf/ directory") Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: Jesper Dangaard Brouer Link: https://lore.kernel.org/bpf/157952560126.1683545.7273054725976032511.stgit@toke.dk Signed-off-by: Greg Kroah-Hartman

samples: bpf: fix syscall_tp due to unused syscall

2019-12-11T23:28:06+00:00

Currently, open() is called from the user program and it calls the syscall 'sys_openat', not the 'sys_open'. This leads to an error of the program of user side, due to the fact that the counter maps are zero since no function such 'sys_open' is called. This commit adds the kernel bpf program which are attached to the tracepoint 'sys_enter_openat' and 'sys_enter_openat'. Fixes: 1da236b6be963 ("bpf: add a test case for syscalls/sys_{enter|exit}_* tracepoints") Signed-off-by: Daniel T. Lee Signed-off-by: Alexei Starovoitov

samples: bpf: Replace symbol compare of trace_event

2019-12-11T23:27:28+00:00

Previously, when this sample is added, commit 1c47910ef8013 ("samples/bpf: add perf_event+bpf example"), a symbol 'sys_read' and 'sys_write' has been used without no prefixes. But currently there are no exact symbols with these under kallsyms and this leads to failure. This commit changes exact compare to substring compare to keep compatible with exact symbol or prefixed symbol. Fixes: 1c47910ef8013 ("samples/bpf: add perf_event+bpf example") Signed-off-by: Daniel T. Lee Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191205080114.19766-2-danieltimlee@gmail.com

samples/bpf: Fix broken xdp_rxq_info due to map order assumptions

2019-12-05T01:54:15+00:00

In the days of using bpf_load.c the order in which the 'maps' sections were defines in BPF side (*_kern.c) file, were used by userspace side to identify the map via using the map order as an index. In effect the order-index is created based on the order the maps sections are stored in the ELF-object file, by the LLVM compiler. This have also carried over in libbpf via API bpf_map__next(NULL, obj) to extract maps in the order libbpf parsed the ELF-object file. When BTF based maps were introduced a new section type ".maps" were created. I found that the LLVM compiler doesn't create the ".maps" sections in the order they are defined in the C-file. The order in the ELF file is based on the order the map pointer is referenced in the code. This combination of changes lead to xdp_rxq_info mixing up the map file-descriptors in userspace, resulting in very broken behaviour, but without warning the user. This patch fix issue by instead using bpf_object__find_map_by_name() to find maps via their names. (Note, this is the ELF name, which can be longer than the name the kernel retains). Fixes: be5bca44aa6b ("samples: bpf: convert some XDP samples from bpf_load to libbpf") Fixes: 451d1dc886b5 ("samples: bpf: update map definition to new syntax BTF-defined map") Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Alexei Starovoitov Acked-by: Toke Høiland-Jørgensen Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/157529025128.29832.5953245340679936909.stgit@firesoul

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2019-11-21T02:11:23+00:00

Daniel Borkmann says: ==================== pull-request: bpf-next 2019-11-20 The following pull-request contains BPF updates for your *net-next* tree. We've added 81 non-merge commits during the last 17 day(s) which contain a total of 120 files changed, 4958 insertions(+), 1081 deletions(-). There are 3 trivial conflicts, resolve it by always taking the chunk from 196e8ca74886c433: <<<<<<< HEAD ======= void *bpf_map_area_mmapable_alloc(u64 size, int numa_node); >>>>>>> 196e8ca74886c433dcfc64a809707074b936aaf5 <<<<<<< HEAD void *bpf_map_area_alloc(u64 size, int numa_node) ======= static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) >>>>>>> 196e8ca74886c433dcfc64a809707074b936aaf5 <<<<<<< HEAD if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { ======= /* kmalloc()'ed memory can't be mmap()'ed */ if (!mmapable && size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { >>>>>>> 196e8ca74886c433dcfc64a809707074b936aaf5 The main changes are: 1) Addition of BPF trampoline which works as a bridge between kernel functions, BPF programs and other BPF programs along with two new use cases: i) fentry/fexit BPF programs for tracing with practically zero overhead to call into BPF (as opposed to k[ret]probes) and ii) attachment of the former to networking related programs to see input/output of networking programs (covering xdpdump use case), from Alexei Starovoitov. 2) BPF array map mmap support and use in libbpf for global data maps; also a big batch of libbpf improvements, among others, support for reading bitfields in a relocatable manner (via libbpf's CO-RE helper API), from Andrii Nakryiko. 3) Extend s390x JIT with usage of relative long jumps and loads in order to lift the current 64/512k size limits on JITed BPF programs there, from Ilya Leoshkevich. 4) Add BPF audit support and emit messages upon successful prog load and unload in order to have a timeline of events, from Daniel Borkmann and Jiri Olsa. 5) Extension to libbpf and xdpsock sample programs to demo the shared umem mode (XDP_SHARED_UMEM) as well as RX-only and TX-only sockets, from Magnus Karlsson. 6) Several follow-up bug fixes for libbpf's auto-pinning code and a new API call named bpf_get_link_xdp_info() for retrieving the full set of prog IDs attached to XDP, from Toke Høiland-Jørgensen. 7) Add BTF support for array of int, array of struct and multidimensional arrays and enable it for skb->cb[] access in kfree_skb test, from Martin KaFai Lau. 8) Fix AF_XDP by using the correct number of channels from ethtool, from Luigi Rizzo. 9) Two fixes for BPF selftest to get rid of a hang in test_tc_tunnel and to avoid xdping to be run as standalone, from Jiri Benc. 10) Various BPF selftest fixes when run with latest LLVM trunk, from Yonghong Song. 11) Fix a memory leak in BPF fentry test run data, from Colin Ian King. 12) Various smaller misc cleanups and improvements mostly all over BPF selftests and samples, from Daniel T. Lee, Andre Guedes, Anders Roxell, Mao Wenan, Yue Haibing. ==================== Signed-off-by: David S. Miller

samples/bpf: Add missing option to xdpsock usage

2019-11-15T21:32:10+00:00

Commit 743e568c1586 (samples/bpf: Add a "force" flag to XDP samples) introduced the '-F' option but missed adding it to the usage() and the 'long_option' array. Fixes: 743e568c1586 (samples/bpf: Add a "force" flag to XDP samples) Signed-off-by: Andre Guedes Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20191114162847.221770-2-andre.guedes@intel.com

samples/bpf: Remove duplicate option from xdpsock

2019-11-15T21:29:17+00:00

The '-f' option is shown twice in the usage(). This patch removes the outdated version. Signed-off-by: Andre Guedes Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20191114162847.221770-1-andre.guedes@intel.com