summaryrefslogtreecommitdiffstats
path: root/tools/lib/bpf
Commit message (Collapse)AuthorAgeFilesLines
...
* | libbpf: Fix probe code to return EPERM if encounteredEelco Chaudron2020-05-131-7/+29
| | | | | | | | | | | | | | | | | | | | | | | | When the probe code was failing for any reason ENOTSUP was returned, even if this was due to not having enough lock space. This patch fixes this by returning EPERM to the user application, so it can respond and increase the RLIMIT_MEMLOCK size. Signed-off-by: Eelco Chaudron <echaudro@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/158927424896.2342.10402475603585742943.stgit@ebuild
* | bpf, libbpf: Replace zero-length array with flexible-arrayGustavo A. R. Silva2020-05-112-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200507185057.GA13981@embeddedor
* | tools/libpf: Add offsetof/container_of macro in bpf_helpers.hYonghong Song2020-05-091-0/+14
| | | | | | | | | | | | | | | | | | | | | | These two helpers will be used later in bpf_iter bpf program bpf_iter_netlink.c. Put them in bpf_helpers.h since they could be useful in other cases. 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/20200509175919.2477104-1-yhs@fb.com
* | tools/libbpf: Add bpf_iter supportYonghong Song2020-05-096-0/+91
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Two new libbpf APIs are added to support bpf_iter: - bpf_program__attach_iter Given a bpf program and additional parameters, which is none now, returns a bpf_link. - bpf_iter_create syscall level API to create a bpf iterator. The macro BPF_SEQ_PRINTF are also introduced. The format looks like: BPF_SEQ_PRINTF(seq, "task id %d\n", pid); This macro can help bpf program writers with nicer bpf_seq_printf syntax similar to the kernel one. 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/20200509175917.2476936-1-yhs@fb.com
* | libbpf: Add support for command BPF_ENABLE_STATSSong Liu2020-05-013-0/+12
| | | | | | | | | | | | | | | | bpf_enable_stats() is added to enable given stats. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200430071506.1408910-3-songliubraving@fb.com
* | libbpf: Fix false uninitialized variable warningAndrii Nakryiko2020-04-301-1/+1
| | | | | | | | | | | | | | | | | | Some versions of GCC falsely detect that vi might not be initialized. That's not true, but let's silence it with NULL initialization. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200430021436.1522502-1-andriin@fb.com
* | libbpf: Fix huge memory leak in libbpf_find_vmlinux_btf_id()Andrii Nakryiko2020-04-281-1/+4
| | | | | | | | | | | | | | | | | | | | BTF object wasn't freed. Fixes: a6ed02cac690 ("libbpf: Load btf_vmlinux only once per object.") Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: KP Singh <kpsingh@google.com> Link: https://lore.kernel.org/bpf/20200429012111.277390-9-andriin@fb.com
* | libbpf: Fix memory leak and possible double-free in hashmap__clearAndrii Nakryiko2020-04-281-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | 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: Alston Tang <alston64@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429012111.277390-5-andriin@fb.com
* | libbpf: Add BTF-defined map-in-map supportAndrii Nakryiko2020-04-282-23/+259
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200429002739.48006-4-andriin@fb.com
* | libbpf: Refactor map creation logic and fix cleanup leakAndrii Nakryiko2020-04-281-105/+121
| | | | | | | | | | | | | | | | | | | | | | | | 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: 57a00f41644f ("libbpf: Add auto-pinning of maps when loading BPF objects") Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200429002739.48006-3-andriin@fb.com
* | libbpf: Refactor BTF-defined map definition parsing logicAndrii Nakryiko2020-04-281-92/+103
| | | | | | | | | | | | | | | | | | Factor out BTF map definition logic into stand-alone routine for easier reuse for map-in-map case. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429002739.48006-2-andriin@fb.com
* | libbpf: Add low-level APIs for new bpf_link commandsAndrii Nakryiko2020-04-283-3/+26
| | | | | | | | | | | | | | | | | | Add low-level API calls for bpf_link_get_next_id() and bpf_link_get_fd_by_id(). Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200429001614.1544-6-andriin@fb.com
* | libbpf: Remove unneeded semicolon in btf_dump_emit_typeZou Wei2020-04-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | Fixes the following coccicheck warning: tools/lib/bpf/btf_dump.c:661:4-5: Unneeded semicolon Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zou Wei <zou_wei@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/1588064829-70613-1-git-send-email-zou_wei@huawei.com
* | libbpf: Return err if bpf_object__load failedMao Wenan2020-04-271-1/+1
| | | | | | | | | | | | | | | | | | | | bpf_object__load() has various return code, when it failed to load object, it must return err instead of -EINVAL. Signed-off-by: Mao Wenan <maowenan@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200426063635.130680-3-maowenan@huawei.com
* | bpf_helpers.h: Add note for building with vmlinux.h or linux/types.hYoshiki Komachi2020-04-261-0/+6
|/ | | | | | | | | | | | | | | | | | | | | | | | The following error was shown when a bpf program was compiled without vmlinux.h auto-generated from BTF: # clang -I./linux/tools/lib/ -I/lib/modules/$(uname -r)/build/include/ \ -O2 -Wall -target bpf -emit-llvm -c bpf_prog.c -o bpf_prog.bc ... In file included from linux/tools/lib/bpf/bpf_helpers.h:5: linux/tools/lib/bpf/bpf_helper_defs.h:56:82: error: unknown type name '__u64' ... It seems that bpf programs are intended for being built together with the vmlinux.h (which will have all the __u64 and other typedefs). But users may mistakenly think "include <linux/types.h>" is missing because the vmlinux.h is not common for non-bpf developers. IMO, an explicit comment therefore should be added to bpf_helpers.h as this patch shows. Signed-off-by: Yoshiki Komachi <komachi.yoshiki@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/1587427527-29399-1-git-send-email-komachi.yoshiki@gmail.com
* libbpf: Only check mode flags in get_xdp_idDavid Ahern2020-04-221-0/+2
| | | | | | | | | | | | The commit in the Fixes tag changed get_xdp_id to only return prog_id if flags is 0, but there are other XDP flags than the modes - e.g., XDP_FLAGS_UPDATE_IF_NOEXIST. Since the intention was only to look at MODE flags, clear other ones before checking if flags is 0. Fixes: f07cbad29741 ("libbpf: Fix bpf_get_link_xdp_id flags handling") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrey Ignatov <rdna@fb.com>
* libbpf: Fix type of old_fd in bpf_xdp_set_link_optsToke Høiland-Jørgensen2020-04-151-1/+1
| | | | | | | | | | | | | | | | The 'old_fd' parameter used for atomic replacement of XDP programs is supposed to be an FD, but was left as a u32 from an earlier iteration of the patch that added it. It was converted to an int when read, so things worked correctly even with negative values, but better change the definition to correctly reflect the intention. Fixes: bd5ca3ef93cd ("libbpf: Add function to set link XDP fd while specifying old program") Reported-by: David Ahern <dsahern@gmail.com> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: David Ahern <dsahern@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200414145025.182163-1-toke@redhat.com
* libbpf: Always specify expected_attach_type on program load if supportedAndrii Nakryiko2020-04-151-44/+82
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For some types of BPF programs that utilize expected_attach_type, libbpf won't set load_attr.expected_attach_type, even if expected_attach_type is known from section definition. This was done to preserve backwards compatibility with old kernels that didn't recognize expected_attach_type attribute yet (which was added in 5e43f899b03a ("bpf: Check attach type at prog load time"). But this is problematic for some BPF programs that utilize newer features that require kernel to know specific expected_attach_type (e.g., extended set of return codes for cgroup_skb/egress programs). This patch makes libbpf specify expected_attach_type by default, but also detect support for this field in kernel and not set it during program load. This allows to have a good metadata for bpf_program (e.g., bpf_program__get_extected_attach_type()), but still work with old kernels (for cases where it can work at all). Additionally, due to expected_attach_type being always set for recognized program types, bpf_program__attach_cgroup doesn't have to do extra checks to determine correct attach type, so remove that additional logic. Also adjust section_names selftest to account for this change. More detailed discussion can be found in [0]. [0] https://lore.kernel.org/bpf/20200412003604.GA15986@rdna-mbp.dhcp.thefacebook.com/ Fixes: 5cf1e9145630 ("bpf: cgroup inet skb programs can return 0 to 3") Fixes: 5e43f899b03a ("bpf: Check attach type at prog load time") Reported-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Andrey Ignatov <rdna@fb.com> Link: https://lore.kernel.org/bpf/20200414182645.1368174-1-andriin@fb.com
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller2020-04-091-3/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Daniel Borkmann says: ==================== pull-request: bpf 2020-04-10 The following pull-request contains BPF updates for your *net* tree. We've added 13 non-merge commits during the last 7 day(s) which contain a total of 13 files changed, 137 insertions(+), 43 deletions(-). The main changes are: 1) JIT code emission fixes for riscv and arm32, from Luke Nelson and Xi Wang. 2) Disable vmlinux BTF info if GCC_PLUGIN_RANDSTRUCT is used, from Slava Bacherikov. 3) Fix oob write in AF_XDP when meta data is used, from Li RongQing. 4) Fix bpf_get_link_xdp_id() handling on single prog when flags are specified, from Andrey Ignatov. 5) Fix sk_assign() BPF helper for request sockets that can have sk_reuseport field uninitialized, from Joe Stringer. 6) Fix mprotect() test case for the BPF LSM, from KP Singh. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * libbpf: Fix bpf_get_link_xdp_id flags handlingAndrey Ignatov2020-04-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently if one of XDP_FLAGS_{DRV,HW,SKB}_MODE flags is passed to bpf_get_link_xdp_id() and there is a single XDP program attached to ifindex, that program's id will be returned by bpf_get_link_xdp_id() in prog_id argument no matter what mode the program is attached in, i.e. flags argument is not taken into account. For example, if there is a single program attached with XDP_FLAGS_SKB_MODE but user calls bpf_get_link_xdp_id() with flags = XDP_FLAGS_DRV_MODE, that skb program will be returned. Fix it by returning info->prog_id only if user didn't specify flags. If flags is specified then return corresponding mode-specific-field from struct xdp_link_info. The initial error was introduced in commit 50db9f073188 ("libbpf: Add a support for getting xdp prog id on ifindex") and then refactored in 473f4e133a12 so 473f4e133a12 is used in the Fixes tag. Fixes: 473f4e133a12 ("libbpf: Add bpf_get_link_xdp_info() function to get more XDP information") Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/0e9e30490b44b447bb2bebc69c7135e7fe7e4e40.1586236080.git.rdna@fb.com
| * libbpf: Initialize *nl_pid so gcc 10 is happyJeremy Cline2020-04-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Builds of Fedora's kernel-tools package started to fail with "may be used uninitialized" warnings for nl_pid in bpf_set_link_xdp_fd() and bpf_get_link_xdp_info() on the s390 architecture. Although libbpf_netlink_open() always returns a negative number when it does not set *nl_pid, the compiler does not determine this and thus believes the variable might be used uninitialized. Assuage gcc's fears by explicitly initializing nl_pid. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1807781 Signed-off-by: Jeremy Cline <jcline@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200404051430.698058-1-jcline@redhat.com
* | Merge tag 'spdx-5.7-rc1' of ↵Linus Torvalds2020-04-031-0/+1
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx Pull SPDX updates from Greg KH: "Here are three SPDX patches for 5.7-rc1. One fixes up the SPDX tag for a single driver, while the other two go through the tree and add SPDX tags for all of the .gitignore files as needed. Nothing too complex, but you will get a merge conflict with your current tree, that should be trivial to handle (one file modified by two things, one file deleted.) All three of these have been in linux-next for a while, with no reported issues other than the merge conflict" * tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: ASoC: MT6660: make spdxcheck.py happy .gitignore: add SPDX License Identifier .gitignore: remove too obvious comments
| * .gitignore: add SPDX License IdentifierMasahiro Yamada2020-03-251-0/+1
| | | | | | | | | | | | | | Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | libbpf: Add support for bpf_link-based cgroup attachmentAndrii Nakryiko2020-03-305-1/+110
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add bpf_program__attach_cgroup(), which uses BPF_LINK_CREATE subcommand to create an FD-based kernel bpf_link. Also add low-level bpf_link_create() API. If expected_attach_type is not specified explicitly with bpf_program__set_expected_attach_type(), libbpf will try to determine proper attach type from BPF program's section definition. Also add support for bpf_link's underlying BPF program replacement: - unconditional through high-level bpf_link__update_program() API; - cmpxchg-like with specifying expected current BPF program through low-level bpf_link_update() API. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200330030001.2312810-4-andriin@fb.com
* | tools/libbpf: Add support for BPF_PROG_TYPE_LSMKP Singh2020-03-304-5/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since BPF_PROG_TYPE_LSM uses the same attaching mechanism as BPF_PROG_TYPE_TRACING, the common logic is refactored into a static function bpf_program__attach_btf_id. A new API call bpf_program__attach_lsm is still added to avoid userspace conflicts if this ever changes in the future. Signed-off-by: KP Singh <kpsingh@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Brendan Jackman <jackmanb@google.com> Reviewed-by: Florent Revest <revest@google.com> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200329004356.27286-7-kpsingh@chromium.org
* | bpf: Introduce BPF_PROG_TYPE_LSMKP Singh2020-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce types and configs for bpf programs that can be attached to LSM hooks. The programs can be enabled by the config option CONFIG_BPF_LSM. Signed-off-by: KP Singh <kpsingh@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Brendan Jackman <jackmanb@google.com> Reviewed-by: Florent Revest <revest@google.com> Reviewed-by: Thomas Garnier <thgarnie@google.com> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: James Morris <jamorris@linux.microsoft.com> Link: https://lore.kernel.org/bpf/20200329004356.27286-2-kpsingh@chromium.org
* | libbpf: Add setter for initial value for internal mapsToke Høiland-Jørgensen2020-03-303-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For internal maps (most notably the maps backing global variables), libbpf uses an internal mmaped area to store the data after opening the object. This data is subsequently copied into the kernel map when the object is loaded. This adds a function to set a new value for that data, which can be used to before it is loaded into the kernel. This is especially relevant for RODATA maps, since those are frozen on load. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200329132253.232541-1-toke@redhat.com
* | libbpf: Add function to set link XDP fd while specifying old programToke Høiland-Jørgensen2020-03-283-1/+42
| | | | | | | | | | | | | | | | | | | | | | This adds a new function to set the XDP fd while specifying the FD of the program to replace, using the newly added IFLA_XDP_EXPECTED_FD netlink parameter. The new function uses the opts struct mechanism to be extendable in the future. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/158515700857.92963.7052131201257841700.stgit@toke.dk
* | libbpf, xsk: Init all ring members in xsk_umem__create and xsk_socket__createFletcher Dunn2020-03-281-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a sharp edge in xsk_umem__create and xsk_socket__create. Almost all of the members of the ring buffer structs are initialized, but the "cached_xxx" variables are not all initialized. The caller is required to zero them. This is needlessly dangerous. The results if you don't do it can be very bad. For example, they can cause xsk_prod_nb_free and xsk_cons_nb_avail to return values greater than the size of the queue. xsk_ring_cons__peek can return an index that does not refer to an item that has been queued. I have confirmed that without this change, my program misbehaves unless I memset the ring buffers to zero before calling the function. Afterwards, my program works without (or with) the memset. Signed-off-by: Fletcher Dunn <fletcherd@valvesoftware.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Magnus Karlsson <magnus.karlsson@intel.com> Link: https://lore.kernel.org/bpf/85f12913cde94b19bfcb598344701c38@valvesoftware.com
* | libbpf: Don't allocate 16M for log buffer by defaultStanislav Fomichev2020-03-262-13/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For each prog/btf load we allocate and free 16 megs of verifier buffer. On production systems it doesn't really make sense because the programs/btf have gone through extensive testing and (mostly) guaranteed to successfully load. Let's assume successful case by default and skip buffer allocation on the first try. If there is an error, start with BPF_LOG_BUF_SIZE and double it on each ENOSPC iteration. v3: * Return -ENOMEM when can't allocate log buffer (Andrii Nakryiko) v2: * Don't allocate the buffer at all on the first try (Andrii Nakryiko) Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200325195521.112210-1-sdf@google.com
* | libbpf: Remove unused parameter `def` to get_map_field_intTobias Klauser2020-03-261-10/+6
| | | | | | | | | | | | | | | | | | | | | | Has been unused since commit ef99b02b23ef ("libbpf: capture value in BTF type info for BTF-defined map defs"). Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200325113655.19341-1-tklauser@distanz.ch
* | bpf, libbpf: Fix ___bpf_kretprobe_args1(x) macro definitionWenbo Zhang2020-03-171-1/+1
| | | | | | | | | | | | | | | | | | | | Use PT_REGS_RC instead of PT_REGS_RET to get ret correctly. Fixes: df8ff35311c8 ("libbpf: Merge selftests' bpf_trace_helpers.h into libbpf's bpf_tracing.h") Signed-off-by: Wenbo Zhang <ethercflow@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200315083252.22274-1-ethercflow@gmail.com
* | libbpf: Provide CO-RE variants of PT_REGS macrosAndrii Nakryiko2020-03-131-0/+103
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Syscall raw tracepoints have struct pt_regs pointer as tracepoint's first argument. After that, reading any of pt_regs fields requires bpf_probe_read(), even for tp_btf programs. Due to that, PT_REGS_PARMx macros are not usable as is. This patch adds CO-RE variants of those macros that use BPF_CORE_READ() to read necessary fields. This provides relocatable architecture-agnostic pt_regs field accesses. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20200313172336.1879637-4-andriin@fb.com
* | libbpf: Ignore incompatible types with matching name during CO-RE relocationAndrii Nakryiko2020-03-131-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When finding target type candidates, ignore forward declarations, functions, and other named types of incompatible kind. Not doing this can cause false errors. See [0] for one such case (due to struct pt_regs forward declaration). [0] https://github.com/iovisor/bcc/pull/2806#issuecomment-598543645 Fixes: ddc7c3042614 ("libbpf: implement BPF CO-RE offset relocation algorithm") Reported-by: Wenbo Zhang <ethercflow@gmail.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20200313172336.1879637-3-andriin@fb.com
* | libbpf: Split BTF presence checks into libbpf- and kernel-specific partsAndrii Nakryiko2020-03-131-5/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Needs for application BTF being present differs between user-space libbpf needs and kernel needs. Currently, BTF is mandatory only in kernel only when BPF application is using STRUCT_OPS. While libbpf itself relies more heavily on presense of BTF: - for BTF-defined maps; - for Kconfig externs; - for STRUCT_OPS as well. Thus, checks for presence and validness of bpf_object's BPF needs to be performed separately, which is patch does. Fixes: 5327644614a1 ("libbpf: Relax check whether BTF is mandatory") Reported-by: Michal Rostecki <mrostecki@opensuse.org> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Cc: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200312185033.736911-1-andriin@fb.com
* | tools/libbpf: Add support for BPF_MODIFY_RETURNKP Singh2020-03-041-0/+4
| | | | | | | | | | | | | | | | Signed-off-by: KP Singh <kpsingh@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200304191853.1529-6-kpsingh@chromium.org
* | libbpf: Assume unsigned values for BTF_KIND_ENUMAndrii Nakryiko2020-03-041-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | Currently, BTF_KIND_ENUM type doesn't record whether enum values should be interpreted as signed or unsigned. In Linux, most enums are unsigned, though, so interpreting them as unsigned matches real world better. Change btf_dump test case to test maximum 32-bit value, instead of negative value. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200303003233.3496043-3-andriin@fb.com
* | libbpf: Fix handling of optional field_name in btf_dump__emit_type_declAndrii Nakryiko2020-03-031-1/+1
| | | | | | | | | | | | | | | | | | | | Internal functions, used by btf_dump__emit_type_decl(), assume field_name is never going to be NULL. Ensure it's always the case. Fixes: 9f81654eebe8 ("libbpf: Expose BTF-to-C type declaration emitting API") Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200303180800.3303471-1-andriin@fb.com
* | libbpf: Add bpf_link pinning/unpinningAndrii Nakryiko2020-03-023-27/+114
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With bpf_link abstraction supported by kernel explicitly, add pinning/unpinning API for links. Also allow to create (open) bpf_link from BPF FS file. This API allows to have an "ephemeral" FD-based BPF links (like raw tracepoint or fexit/freplace attachments) surviving user process exit, by pinning them in a BPF FS, which is an important use case for long-running BPF programs. As part of this, expose underlying FD for bpf_link. While legacy bpf_link's might not have a FD associated with them (which will be expressed as a bpf_link with fd=-1), kernel's abstraction is based around FD-based usage, so match it closely. This, subsequently, allows to have a generic pinning/unpinning API for generalized bpf_link. For some types of bpf_links kernel might not support pinning, in which case bpf_link__pin() will return error. With FD being part of generic bpf_link, also get rid of bpf_link_fd in favor of using vanialla bpf_link. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200303043159.323675-3-andriin@fb.com
* | libbpf: Merge selftests' bpf_trace_helpers.h into libbpf's bpf_tracing.hAndrii Nakryiko2020-03-021-0/+118
| | | | | | | | | | | | | | | | | | Move BPF_PROG, BPF_KPROBE, and BPF_KRETPROBE macro into libbpf's bpf_tracing.h header to make it available for non-selftests users. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200229231112.1240137-5-andriin@fb.com
* | libbpf: Fix use of PT_REGS_PARM macros with vmlinux.hAndrii Nakryiko2020-03-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Add detection of vmlinux.h to bpf_tracing.h header for PT_REGS macro. Currently, BPF applications have to define __KERNEL__ symbol to use correct definition of struct pt_regs on x86 arch. This is due to different field names under internal kernel vs UAPI conditions. To make this more transparent for users, detect vmlinux.h by checking __VMLINUX_H__ symbol. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200229231112.1240137-3-andriin@fb.com
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller2020-02-213-7/+40
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Daniel Borkmann says: ==================== pull-request: bpf-next 2020-02-21 The following pull-request contains BPF updates for your *net-next* tree. We've added 25 non-merge commits during the last 4 day(s) which contain a total of 33 files changed, 2433 insertions(+), 161 deletions(-). The main changes are: 1) Allow for adding TCP listen sockets into sock_map/hash so they can be used with reuseport BPF programs, from Jakub Sitnicki. 2) Add a new bpf_program__set_attach_target() helper for adding libbpf support to specify the tracepoint/function dynamically, from Eelco Chaudron. 3) Add bpf_read_branch_records() BPF helper which helps use cases like profile guided optimizations, from Daniel Xu. 4) Enable bpf_perf_event_read_value() in all tracing programs, from Song Liu. 5) Relax BTF mandatory check if only used for libbpf itself e.g. to process BTF defined maps, from Andrii Nakryiko. 6) Move BPF selftests -mcpu compilation attribute from 'probe' to 'v3' as it has been observed that former fails in envs with low memlock, from Yonghong Song. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * libbpf: Add support for dynamic program attach targetEelco Chaudron2020-02-203-4/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when you want to attach a trace program to a bpf program the section name needs to match the tracepoint/function semantics. However the addition of the bpf_program__set_attach_target() API allows you to specify the tracepoint/function dynamically. The call flow would look something like this: xdp_fd = bpf_prog_get_fd_by_id(id); trace_obj = bpf_object__open_file("func.o", NULL); prog = bpf_object__find_program_by_title(trace_obj, "fentry/myfunc"); bpf_program__set_expected_attach_type(prog, BPF_TRACE_FENTRY); bpf_program__set_attach_target(prog, xdp_fd, "xdpfilt_blk_all"); bpf_object__load(trace_obj) Signed-off-by: Eelco Chaudron <echaudro@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/158220519486.127661.7964708960649051384.stgit@xdp-tutorial
| * libbpf: Bump libpf current version to v0.0.8Eelco Chaudron2020-02-201-0/+3
| | | | | | | | | | | | | | | | | | New development cycles starts, bump to v0.0.8. Signed-off-by: Eelco Chaudron <echaudro@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/158220518424.127661.8278643006567775528.stgit@xdp-tutorial
| * libbpf: Relax check whether BTF is mandatoryAndrii Nakryiko2020-02-201-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If BPF program is using BTF-defined maps, BTF is required only for libbpf itself to process map definitions. If after that BTF fails to be loaded into kernel (e.g., if it doesn't support BTF at all), this shouldn't prevent valid BPF program from loading. Existing retry-without-BTF logic for creating maps will succeed to create such maps without any problems. So, presence of .maps section shouldn't make BTF required for kernel. Update the check accordingly. Validated by ensuring simple BPF program with BTF-defined maps is still loaded on old kernel without BTF support and map is correctly parsed and created. Fixes: abd29c931459 ("libbpf: allow specifying map definitions using BTF") Reported-by: Julia Kartseva <hex@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200220062635.1497872-1-andriin@fb.com
* | libbpf: Sanitise internal map names so they are not rejected by the kernelToke Høiland-Jørgensen2020-02-181-1/+7
|/ | | | | | | | | | | | | | | | The kernel only accepts map names with alphanumeric characters, underscores and periods in their name. However, the auto-generated internal map names used by libbpf takes their prefix from the user-supplied BPF object name, which has no such restriction. This can lead to "Invalid argument" errors when trying to load a BPF program using global variables. Fix this by sanitising the map names, replacing any non-allowed characters with underscores. Fixes: d859900c4c56 ("bpf, libbpf: support global data/bss/rodata sections") Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200217171701.215215-1-toke@redhat.com
* libbpf: Fix realloc usage in bpf_core_find_candsAndrii Nakryiko2020-01-241-1/+3
| | | | | | | | | | | | | Fix bug requesting invalid size of reallocated array when constructing CO-RE relocation candidate list. This can cause problems if there are many potential candidates and a very fine-grained memory allocator bucket sizes are used. Fixes: ddc7c3042614 ("libbpf: implement BPF CO-RE offset relocation algorithm") Reported-by: William Smith <williampsmith@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200124201847.212528-1-andriin@fb.com
* libbpf: Improve handling of failed CO-RE relocationsAndrii Nakryiko2020-01-242-40/+61
| | | | | | | | | | | | | | | | | | | | | | | | Previously, if libbpf failed to resolve CO-RE relocation for some instructions, it would either return error immediately, or, if .relaxed_core_relocs option was set, would replace relocatable offset/imm part of an instruction with a bogus value (-1). Neither approach is good, because there are many possible scenarios where relocation is expected to fail (e.g., when some field knowingly can be missing on specific kernel versions). On the other hand, replacing offset with invalid one can hide programmer errors, if this relocation failue wasn't anticipated. This patch deprecates .relaxed_core_relocs option and changes the approach to always replacing instruction, for which relocation failed, with invalid BPF helper call instruction. For cases where this is expected, BPF program should already ensure that that instruction is unreachable, in which case this invalid instruction is going to be silently ignored. But if instruction wasn't guarded, BPF program will be rejected at verification step with verifier log pointing precisely to the place in assembly where the problem is. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20200124053837.2434679-1-andriin@fb.com
* libbpf: Add support for program extensionsAlexei Starovoitov2020-01-225-4/+17
| | | | | | | | | | | | | | | | | Add minimal support for program extensions. bpf_object_open_opts() needs to be called with attach_prog_fd = target_prog_fd and BPF program extension needs to have in .c file section definition like SEC("freplace/func_to_be_replaced"). libbpf will search for "func_to_be_replaced" in the target_prog_fd's BTF and will pass it in attach_btf_id to the kernel. This approach works for tests, but more compex use case may need to request function name (and attach_btf_id that kernel sees) to be more dynamic. Such API will be added in future patches. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200121005348.2769920-3-ast@kernel.org
* libbpf: Load btf_vmlinux only once per object.KP Singh2020-01-171-52/+101
| | | | | | | | | | | | | | | | | | | As more programs (TRACING, STRUCT_OPS, and upcoming LSM) use vmlinux BTF information, loading the BTF vmlinux information for every program in an object is sub-optimal. The fix was originally proposed in: https://lore.kernel.org/bpf/CAEf4BzZodr3LKJuM7QwD38BiEH02Cc1UbtnGpVkCJ00Mf+V_Qg@mail.gmail.com/ The btf_vmlinux is populated in the object if any of the programs in the object requires it just before the programs are loaded and freed after the programs finish loading. Reported-by: Andrii Nakryiko <andrii.nakryiko@gmail.com> Signed-off-by: KP Singh <kpsingh@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Brendan Jackman <jackmanb@chromium.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200117212825.11755-1-kpsingh@chromium.org
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-29 20:13:21 +0000