kernel/linux.git/tools/bpf/bpftool/map.c, branch linux-5.11.y

bpftool: Fix maybe-uninitialized warnings

2021-05-14T08:50:00+00:00

[ Upstream commit 4bbb3583687051ef99966ddaeb1730441b777d40 ] Somehow when bpftool is compiled in -Og mode, compiler produces new warnings about possibly uninitialized variables. Fix all the reported problems. Fixes: 2119f2189df1 ("bpftool: add C output format option to btf dump subcommand") Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20210313210920.1959628-3-andrii@kernel.org Signed-off-by: Sasha Levin

bpftool: Add support for task local storage

2020-11-06T16:08:37+00:00

Updates the binary to handle the BPF_MAP_TYPE_TASK_STORAGE as "task_storage" for printing and parsing. Also updates the documentation and bash completion Signed-off-by: KP Singh Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20201106103747.2780972-5-kpsingh@chromium.org

tools: bpftool: Add "inner_map" to "bpftool map create" outer maps

2020-09-11T00:29:21+00:00

There is no support for creating maps of types array-of-map or hash-of-map in bpftool. This is because the kernel needs an inner_map_fd to collect metadata on the inner maps to be supported by the new map, but bpftool does not provide a way to pass this file descriptor. Add a new optional "inner_map" keyword that can be used to pass a reference to a map, retrieve a fd to that map, and pass it as the inner_map_fd. Add related documentation and bash completion. Note that we can reference the inner map by its name, meaning we can have several times the keyword "name" with different meanings (mandatory outer map name, and possibly a name to use to find the inner_map_fd). The bash completion will offer it just once, and will not suggest "name" on the following command: # bpftool map create /sys/fs/bpf/my_outer_map type hash_of_maps \ inner_map name my_inner_map [TAB] Fixing that specific case seems too convoluted. Completion will work as expected, however, if the outer map name comes first and the "inner_map name ..." is passed second. Signed-off-by: Quentin Monnet Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200910102652.10509-4-quentin@isovalent.com

tools: bpftool: Keep errors for map-of-map dumps if distinct from ENOENT

2020-09-11T00:29:20+00:00

When dumping outer maps or prog_array maps, and on lookup failure, bpftool simply skips the entry with no error message. This is because the kernel returns non-zero when no value is found for the provided key, which frequently happen for those maps if they have not been filled. When such a case occurs, errno is set to ENOENT. It seems unlikely we could receive other error codes at this stage (we successfully retrieved map info just before), but to be on the safe side, let's skip the entry only if errno was ENOENT, and not for the other errors. v3: New patch Signed-off-by: Quentin Monnet Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200910102652.10509-3-quentin@isovalent.com

tools: bpftool: Clean up function to dump map entry

2020-09-11T00:29:20+00:00

The function used to dump a map entry in bpftool is a bit difficult to follow, as a consequence to earlier refactorings. There is a variable ("num_elems") which does not appear to be necessary, and the error handling would look cleaner if moved to its own function. Let's clean it up. No functional change. v2: - v1 was erroneously removing the check on fd maps in an attempt to get support for outer map dumps. This is already working. Instead, v2 focuses on cleaning up the dump_map_elem() function, to avoid similar confusion in the future. Signed-off-by: Quentin Monnet Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200910102652.10509-2-quentin@isovalent.com

bpf: Implement bpf_local_storage for inodes

2020-08-25T22:00:04+00:00

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 Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200825182919.1118197-6-kpsingh@chromium.org

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

2020-07-05T00:48:34+00:00

Daniel Borkmann says: ==================== pull-request: bpf-next 2020-07-04 The following pull-request contains BPF updates for your *net-next* tree. We've added 73 non-merge commits during the last 17 day(s) which contain a total of 106 files changed, 5233 insertions(+), 1283 deletions(-). The main changes are: 1) bpftool ability to show PIDs of processes having open file descriptors for BPF map/program/link/BTF objects, relying on BPF iterator progs to extract this info efficiently, from Andrii Nakryiko. 2) Addition of BPF iterator progs for dumping TCP and UDP sockets to seq_files, from Yonghong Song. 3) Support access to BPF map fields in struct bpf_map from programs through BTF struct access, from Andrey Ignatov. 4) Add a bpf_get_task_stack() helper to be able to dump /proc/*/stack via seq_file from BPF iterator progs, from Song Liu. 5) Make SO_KEEPALIVE and related options available to bpf_setsockopt() helper, from Dmitry Yakunin. 6) Optimize BPF sk_storage selection of its caching index, from Martin KaFai Lau. 7) Removal of redundant synchronize_rcu()s from BPF map destruction which has been a historic leftover, from Alexei Starovoitov. 8) Several improvements to test_progs to make it easier to create a shell loop that invokes each test individually which is useful for some CIs, from Jesper Dangaard Brouer. 9) Fix bpftool prog dump segfault when compiled without skeleton code on older clang versions, from John Fastabend. 10) Bunch of cleanups and minor improvements, from various others. ==================== Signed-off-by: David S. Miller

tools, bpftool: Define prog_type_name array only once

2020-06-25T14:06:01+00:00

Define prog_type_name in prog.c instead of main.h so it is only defined once. This leads to a slight decrease in the binary size of bpftool. Before: text data bss dec hex filename 401032 11936 1573160 1986128 1e4e50 bpftool After: text data bss dec hex filename 399024 11168 1573160 1983352 1e4378 bpftool Signed-off-by: Tobias Klauser Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200624143124.12914-1-tklauser@distanz.ch

Merge up to bpf_probe_read_kernel_str() fix into bpf-next

2020-06-23T22:33:41+00:00

tools/bpftool: Show info for processes holding BPF map/prog/link/btf FDs

2020-06-23T00:01:49+00:00

Add bpf_iter-based way to find all the processes that hold open FDs against BPF object (map, prog, link, btf). bpftool always attempts to discover this, but will silently give up if kernel doesn't yet support bpf_iter BPF programs. Process name and PID are emitted for each process (task group). Sample output for each of 4 BPF objects: $ sudo ./bpftool prog show 2694: cgroup_device tag 8c42dee26e8cd4c2 gpl loaded_at 2020-06-16T15:34:32-0700 uid 0 xlated 648B jited 409B memlock 4096B pids systemd(1) 2907: cgroup_skb name egress tag 9ad187367cf2b9e8 gpl loaded_at 2020-06-16T18:06:54-0700 uid 0 xlated 48B jited 59B memlock 4096B map_ids 2436 btf_id 1202 pids test_progs(2238417), test_progs(2238445) $ sudo ./bpftool map show 2436: array name test_cgr.bss flags 0x400 key 4B value 8B max_entries 1 memlock 8192B btf_id 1202 pids test_progs(2238417), test_progs(2238445) 2445: array name pid_iter.rodata flags 0x480 key 4B value 4B max_entries 1 memlock 8192B btf_id 1214 frozen pids bpftool(2239612) $ sudo ./bpftool link show 61: cgroup prog 2908 cgroup_id 375301 attach_type egress pids test_progs(2238417), test_progs(2238445) 62: cgroup prog 2908 cgroup_id 375344 attach_type egress pids test_progs(2238417), test_progs(2238445) $ sudo ./bpftool btf show 1202: size 1527B prog_ids 2908,2907 map_ids 2436 pids test_progs(2238417), test_progs(2238445) 1242: size 34684B pids bpftool(2258892) Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200619231703.738941-9-andriin@fb.com