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2023-04-27Merge tag 'mm-nonmm-stable-2023-04-27-16-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: "Mainly singleton patches all over the place. Series of note are: - updates to scripts/gdb from Glenn Washburn - kexec cleanups from Bjorn Helgaas" * tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (50 commits) mailmap: add entries for Paul Mackerras libgcc: add forward declarations for generic library routines mailmap: add entry for Oleksandr ocfs2: reduce ioctl stack usage fs/proc: add Kthread flag to /proc/$pid/status ia64: fix an addr to taddr in huge_pte_offset() checkpatch: introduce proper bindings license check epoll: rename global epmutex scripts/gdb: add GDB convenience functions $lx_dentry_name() and $lx_i_dentry() scripts/gdb: create linux/vfs.py for VFS related GDB helpers uapi/linux/const.h: prefer ISO-friendly __typeof__ delayacct: track delays from IRQ/SOFTIRQ scripts/gdb: timerlist: convert int chunks to str scripts/gdb: print interrupts scripts/gdb: raise error with reduced debugging information scripts/gdb: add a Radix Tree Parser lib/rbtree: use '+' instead of '|' for setting color. proc/stat: remove arch_idle_time() checkpatch: check for misuse of the link tags checkpatch: allow Closes tags with links ...
2023-04-21tools: bpftool: print netfilter link infoFlorian Westphal
Dump protocol family, hook and priority value: $ bpftool link 2: netfilter prog 14 ip input prio -128 pids install(3264) 5: netfilter prog 14 ip6 forward prio 21 pids a.out(3387) 9: netfilter prog 14 ip prerouting prio 123 pids a.out(5700) 10: netfilter prog 14 ip input prio 21 pids test2(5701) v2: Quentin Monnet suggested to also add 'bpftool net' support: $ bpftool net xdp: tc: flow_dissector: netfilter: ip prerouting prio 21 prog_id 14 ip input prio -128 prog_id 14 ip input prio 21 prog_id 14 ip forward prio 21 prog_id 14 ip output prio 21 prog_id 14 ip postrouting prio 21 prog_id 14 'bpftool net' only dumps netfilter link type, links are sorted by protocol family, hook and priority. v5: fix bpf ci failure: libbpf needs small update to prog_type_name[] and probe_prog_load helper. v4: don't fail with -EOPNOTSUPP in libbpf probe_prog_load, update prog_type_name[] with "netfilter" entry (bpf ci) v3: fix bpf.h copy, 'reserved' member was removed (Alexei) use p_err, not fprintf (Quentin) Suggested-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/eeeaac99-9053-90c2-aa33-cc1ecb1ae9ca@isovalent.com/ Reviewed-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Florian Westphal <fw@strlen.de> Link: https://lore.kernel.org/r/20230421170300.24115-6-fw@strlen.de Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-18libbpf: mark bpf_iter_num_{new,next,destroy} as __weakAndrii Nakryiko
Mark bpf_iter_num_{new,next,destroy}() kfuncs declared for bpf_for()/bpf_repeat() macros as __weak to allow users to feature-detect their presence and guard bpf_for()/bpf_repeat() loops accordingly for backwards compatibility with old kernels. Now that libbpf supports kfunc calls poisoning and better reporting of unresolved (but called) kfuncs, declaring number iterator kfuncs in bpf_helpers.h won't degrade user experience and won't cause unnecessary kernel feature dependencies. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230418002148.3255690-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-18libbpf: move bpf_for(), bpf_for_each(), and bpf_repeat() into bpf_helpers.hAndrii Nakryiko
To make it easier for bleeding-edge BPF applications, such as sched_ext, to utilize open-coded iterators, move bpf_for(), bpf_for_each(), and bpf_repeat() macros from selftests/bpf-internal bpf_misc.h helper, to libbpf-provided bpf_helpers.h header. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230418002148.3255690-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-18libbpf: improve handling of unresolved kfuncsAndrii Nakryiko
Currently, libbpf leaves `call #0` instruction for __weak unresolved kfuncs, which might lead to a confusing verifier log situations, where invalid `call #0` will be treated as successfully validated. We can do better. Libbpf already has an established mechanism of poisoning instructions that failed some form of resolution (e.g., CO-RE relocation and BPF map set to not be auto-created). Libbpf doesn't fail them outright to allow users to guard them through other means, and as long as BPF verifier can prove that such poisoned instructions cannot be ever reached, this doesn't consistute an invalid BPF program. If user didn't guard such code, libbpf will extract few pieces of information to tie such poisoned instructions back to additional information about what entitity wasn't resolved (e.g., BPF map name, or CO-RE relocation information). __weak unresolved kfuncs fit this model well, so this patch extends libbpf with poisioning and log fixup logic for kfunc calls. Note, this poisoning is done only for kfunc *calls*, not kfunc address resolution (ldimm64 instructions). The former cannot be ever valid, if reached, so it's safe to poison them. The latter is a valid mechanism to check if __weak kfunc ksym was resolved, and do necessary guarding and work arounds based on this result, supported in most recent kernels. As such, libbpf keeps such ldimm64 instructions as loading zero, never poisoning them. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230418002148.3255690-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-18libbpf: report vmlinux vs module name when dealing with ksymsAndrii Nakryiko
Currently libbpf always reports "kernel" as a source of ksym BTF type, which is ambiguous given ksym's BTF can come from either vmlinux or kernel module BTFs. Make this explicit and log module name, if used BTF is from kernel module. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230418002148.3255690-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-18libbpf: misc internal libbpf clean ups around log fixupAndrii Nakryiko
Normalize internal constants, field names, and comments related to log fixup. Also add explicit `ext_idx` alias for relocation where relocation is pointing to extern description for additional information. No functional changes, just a clean up before subsequent additions. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230418002148.3255690-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-13Daniel Borkmann says:Jakub Kicinski
==================== pull-request: bpf-next 2023-04-13 We've added 260 non-merge commits during the last 36 day(s) which contain a total of 356 files changed, 21786 insertions(+), 11275 deletions(-). The main changes are: 1) Rework BPF verifier log behavior and implement it as a rotating log by default with the option to retain old-style fixed log behavior, from Andrii Nakryiko. 2) Adds support for using {FOU,GUE} encap with an ipip device operating in collect_md mode and add a set of BPF kfuncs for controlling encap params, from Christian Ehrig. 3) Allow BPF programs to detect at load time whether a particular kfunc exists or not, and also add support for this in light skeleton, from Alexei Starovoitov. 4) Optimize hashmap lookups when key size is multiple of 4, from Anton Protopopov. 5) Enable RCU semantics for task BPF kptrs and allow referenced kptr tasks to be stored in BPF maps, from David Vernet. 6) Add support for stashing local BPF kptr into a map value via bpf_kptr_xchg(). This is useful e.g. for rbtree node creation for new cgroups, from Dave Marchevsky. 7) Fix BTF handling of is_int_ptr to skip modifiers to work around tracing issues where a program cannot be attached, from Feng Zhou. 8) Migrate a big portion of test_verifier unit tests over to test_progs -a verifier_* via inline asm to ease {read,debug}ability, from Eduard Zingerman. 9) Several updates to the instruction-set.rst documentation which is subject to future IETF standardization (https://lwn.net/Articles/926882/), from Dave Thaler. 10) Fix BPF verifier in the __reg_bound_offset's 64->32 tnum sub-register known bits information propagation, from Daniel Borkmann. 11) Add skb bitfield compaction work related to BPF with the overall goal to make more of the sk_buff bits optional, from Jakub Kicinski. 12) BPF selftest cleanups for build id extraction which stand on its own from the upcoming integration work of build id into struct file object, from Jiri Olsa. 13) Add fixes and optimizations for xsk descriptor validation and several selftest improvements for xsk sockets, from Kal Conley. 14) Add BPF links for struct_ops and enable switching implementations of BPF TCP cong-ctls under a given name by replacing backing struct_ops map, from Kui-Feng Lee. 15) Remove a misleading BPF verifier env->bypass_spec_v1 check on variable offset stack read as earlier Spectre checks cover this, from Luis Gerhorst. 16) Fix issues in copy_from_user_nofault() for BPF and other tracers to resemble copy_from_user_nmi() from safety PoV, from Florian Lehner and Alexei Starovoitov. 17) Add --json-summary option to test_progs in order for CI tooling to ease parsing of test results, from Manu Bretelle. 18) Batch of improvements and refactoring to prep for upcoming bpf_local_storage conversion to bpf_mem_cache_{alloc,free} allocator, from Martin KaFai Lau. 19) Improve bpftool's visual program dump which produces the control flow graph in a DOT format by adding C source inline annotations, from Quentin Monnet. 20) Fix attaching fentry/fexit/fmod_ret/lsm to modules by extracting the module name from BTF of the target and searching kallsyms of the correct module, from Viktor Malik. 21) Improve BPF verifier handling of '<const> <cond> <non_const>' to better detect whether in particular jmp32 branches are taken, from Yonghong Song. 22) Allow BPF TCP cong-ctls to write app_limited of struct tcp_sock. A built-in cc or one from a kernel module is already able to write to app_limited, from Yixin Shen. Conflicts: Documentation/bpf/bpf_devel_QA.rst b7abcd9c656b ("bpf, doc: Link to submitting-patches.rst for general patch submission info") 0f10f647f455 ("bpf, docs: Use internal linking for link to netdev subsystem doc") https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/ include/net/ip_tunnels.h bc9d003dc48c3 ("ip_tunnel: Preserve pointer const in ip_tunnel_info_opts") ac931d4cdec3d ("ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices") https://lore.kernel.org/all/20230413161235.4093777-1-broonie@kernel.org/ net/bpf/test_run.c e5995bc7e2ba ("bpf, test_run: fix crashes due to XDP frame overwriting/corruption") 294635a8165a ("bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES") https://lore.kernel.org/all/20230320102619.05b80a98@canb.auug.org.au/ ==================== Link: https://lore.kernel.org/r/20230413191525.7295-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-11libbpf: Wire through log_true_size for bpf_btf_load() APIAndrii Nakryiko
Similar to what we did for bpf_prog_load() in previous patch, wire returning of log_true_size value from kernel back to the user through OPTS out field. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20230406234205.323208-17-andrii@kernel.org
2023-04-11libbpf: Wire through log_true_size returned from kernel for BPF_PROG_LOADAndrii Nakryiko
Add output-only log_true_size field to bpf_prog_load_opts to return bpf_attr->log_true_size value back from bpf() syscall. Note, that we have to drop const modifier from opts in bpf_prog_load(). This could potentially cause compilation error for some users. But the usual practice is to define bpf_prog_load_ops as a local variable next to bpf_prog_load() call and pass pointer to it, so const vs non-const makes no difference and won't even come up in most (if not all) cases. There are no runtime and ABI backwards/forward compatibility issues at all. If user provides old struct bpf_prog_load_opts, libbpf won't set new fields. If old libbpf is provided new bpf_prog_load_opts, nothing will happen either as old libbpf doesn't yet know about this new field. Adding a new variant of bpf_prog_load() just for this seems like a big and unnecessary overkill. As a corroborating evidence is the fact that entire selftests/bpf code base required not adjustment whatsoever. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20230406234205.323208-16-andrii@kernel.org
2023-04-11libbpf: Don't enforce unnecessary verifier log restrictions on libbpf sideAndrii Nakryiko
This basically prevents any forward compatibility. And we either way just return -EINVAL, which would otherwise be returned from bpf() syscall anyways. Similarly, drop enforcement of non-NULL log_buf when log_level > 0. This won't be true anymore soon. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Lorenz Bauer <lmb@isovalent.com> Link: https://lore.kernel.org/bpf/20230406234205.323208-5-andrii@kernel.org
2023-04-08ELF: fix all "Elf" typosAlexey Dobriyan
ELF is acronym and therefore should be spelled in all caps. I left one exception at Documentation/arm/nwfpe/nwfpe.rst which looks like being written in the first person. Link: https://lkml.kernel.org/r/Y/3wGWQviIOkyLJW@p183 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-29libbpf: disassociate section handler on explicit bpf_program__set_type() callAndrii Nakryiko
If user explicitly overrides programs's type with bpf_program__set_type() API call, we need to disassociate whatever SEC_DEF handler libbpf determined initially based on program's SEC() definition, as it's not goind to be valid anymore and could lead to crashes and/or confusing failures. Also, fix up bpf_prog_test_load() helper in selftests/bpf, which is force-setting program type (even if that's completely unnecessary; this is quite a legacy piece of code), and thus should expect auto-attach to not work, yet one of the tests explicitly relies on auto-attach for testing. Instead, force-set program type only if it differs from the desired one. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230327185202.1929145-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-27libbpf: Fix double-free when linker processes empty sectionsEduard Zingerman
Double-free error in bpf_linker__free() was reported by James Hilliard. The error is caused by miss-use of realloc() in extend_sec(). The error occurs when two files with empty sections of the same name are linked: - when first file is processed: - extend_sec() calls realloc(dst->raw_data, dst_align_sz) with dst->raw_data == NULL and dst_align_sz == 0; - dst->raw_data is set to a special pointer to a memory block of size zero; - when second file is processed: - extend_sec() calls realloc(dst->raw_data, dst_align_sz) with dst->raw_data == <special pointer> and dst_align_sz == 0; - realloc() "frees" dst->raw_data special pointer and returns NULL; - extend_sec() exits with -ENOMEM, and the old dst->raw_data value is preserved (it is now invalid); - eventually, bpf_linker__free() attempts to free dst->raw_data again. This patch fixes the bug by avoiding -ENOMEM exit for dst_align_sz == 0. The fix was suggested by Andrii Nakryiko <andrii.nakryiko@gmail.com>. Reported-by: James Hilliard <james.hilliard1@gmail.com> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: James Hilliard <james.hilliard1@gmail.com> Link: https://lore.kernel.org/bpf/CADvTj4o7ZWUikKwNTwFq0O_AaX+46t_+Ca9gvWMYdWdRtTGeHQ@mail.gmail.com/ Link: https://lore.kernel.org/bpf/20230328004738.381898-3-eddyz87@gmail.com
2023-03-27libbpf: Ensure print callback usage is thread-safeJP Kobryn
This patch prevents races on the print function pointer, allowing the libbpf_set_print() function to become thread-safe. Signed-off-by: JP Kobryn <inwardvessel@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230325010845.46000-1-inwardvessel@gmail.com
2023-03-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Conflicts: drivers/net/ethernet/mellanox/mlx5/core/en_tc.c 6e9d51b1a5cb ("net/mlx5e: Initialize link speed to zero") 1bffcea42926 ("net/mlx5e: Add devlink hairpin queues parameters") https://lore.kernel.org/all/20230324120623.4ebbc66f@canb.auug.org.au/ https://lore.kernel.org/all/20230321211135.47711-1-saeed@kernel.org/ Adjacent changes: drivers/net/phy/phy.c 323fe43cf9ae ("net: phy: Improved PHY error reporting in state machine") 4203d84032e2 ("net: phy: Ensure state transitions are processed from phy_stop()") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-22libbpf: Use .struct_ops.link section to indicate a struct_ops with a link.Kui-Feng Lee
Flags a struct_ops is to back a bpf_link by putting it to the ".struct_ops.link" section. Once it is flagged, the created struct_ops can be used to create a bpf_link or update a bpf_link that has been backed by another struct_ops. Signed-off-by: Kui-Feng Lee <kuifeng@meta.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230323032405.3735486-8-kuifeng@meta.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-03-22libbpf: Update a bpf_link with another struct_ops.Kui-Feng Lee
Introduce bpf_link__update_map(), which allows to atomically update underlying struct_ops implementation for given struct_ops BPF link. Also add old_map_fd to struct bpf_link_update_opts to handle BPF_F_REPLACE feature. Signed-off-by: Kui-Feng Lee <kuifeng@meta.com> Link: https://lore.kernel.org/r/20230323032405.3735486-7-kuifeng@meta.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-03-22libbpf: Create a bpf_link in bpf_map__attach_struct_ops().Kui-Feng Lee
bpf_map__attach_struct_ops() was creating a dummy bpf_link as a placeholder, but now it is constructing an authentic one by calling bpf_link_create() if the map has the BPF_F_LINK flag. You can flag a struct_ops map with BPF_F_LINK by calling bpf_map__set_map_flags(). Signed-off-by: Kui-Feng Lee <kuifeng@meta.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230323032405.3735486-5-kuifeng@meta.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-03-22libbpf: Support kfunc detection in light skeleton.Alexei Starovoitov
Teach gen_loader to find {btf_id, btf_obj_fd} of kernel variables and kfuncs and populate corresponding ld_imm64 and bpf_call insns. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230321203854.3035-4-alexei.starovoitov@gmail.com
2023-03-22libbpf: Rename RELO_EXTERN_VAR/FUNC.Alexei Starovoitov
RELO_EXTERN_VAR/FUNC names are not correct anymore. RELO_EXTERN_VAR represent ksym symbol in ld_imm64 insn. It can point to kernel variable or kfunc. Rename RELO_EXTERN_VAR->RELO_EXTERN_LD64 and RELO_EXTERN_FUNC->RELO_EXTERN_CALL to match what they actually represent. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/bpf/20230321203854.3035-2-alexei.starovoitov@gmail.com
2023-03-20libbpf: Explicitly call write to append content to fileLiu Pan
Write data to fd by calling "vdprintf", in most implementations of the standard library, the data is finally written by the writev syscall. But "uprobe_events/kprobe_events" does not allow segmented writes, so switch the "append_to_file" function to explicit write() call. Signed-off-by: Liu Pan <patteliu@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230320030720.650-1-patteliu@gmail.com
2023-03-20libbpf: Fix ld_imm64 copy logic for ksym in light skeleton.Alexei Starovoitov
Unlike normal libbpf the light skeleton 'loader' program is doing btf_find_by_name_kind() call at run-time to find ksym in the kernel and populate its {btf_id, btf_obj_fd} pair in ld_imm64 insn. To avoid doing the search multiple times for the same ksym it remembers the first patched ld_imm64 insn and copies {btf_id, btf_obj_fd} from it into subsequent ld_imm64 insn. Fix a bug in copying logic, since it may incorrectly clear BPF_PSEUDO_BTF_ID flag. Also replace always true if (btf_obj_fd >= 0) check with unconditional JMP_JA to clarify the code. Fixes: d995816b77eb ("libbpf: Avoid reload of imm for weak, unresolved, repeating ksym") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230319203014.55866-1-alexei.starovoitov@gmail.com
2023-03-17libbpf: Introduce bpf_ksym_exists() macro.Alexei Starovoitov
Introduce bpf_ksym_exists() macro that can be used by BPF programs to detect at load time whether particular ksym (either variable or kfunc) is present in the kernel. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230317201920.62030-4-alexei.starovoitov@gmail.com
2023-03-17libbpf: Fix relocation of kfunc ksym in ld_imm64 insn.Alexei Starovoitov
void *p = kfunc; -> generates ld_imm64 insn. kfunc() -> generates bpf_call insn. libbpf patches bpf_call insn correctly while only btf_id part of ld_imm64 is set in the former case. Which means that pointers to kfuncs in modules are not patched correctly and the verifier rejects load of such programs due to btf_id being out of range. Fix libbpf to patch ld_imm64 for kfunc. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230317201920.62030-3-alexei.starovoitov@gmail.com
2023-03-16libbpf: Ignore warnings about "inefficient alignment"Daniel Müller
Some consumers of libbpf compile the code base with different warnings enabled. In a report for perf, for example, -Wpacked was set which caused warnings about "inefficient alignment" to be emitted on a subset of supported architectures. With this change we silence specifically those warnings, as we intentionally worked with packed structs. This is a similar resolution as in b2f10cd4e805 ("perf cpumap: Fix alignment for masks in event encoding"). Fixes: 1eebcb60633f ("libbpf: Implement basic zip archive parsing support") Reported-by: Linux Kernel Functional Testing <lkft@linaro.org> Signed-off-by: Daniel Müller <deso@posteo.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/bpf/CA+G9fYtBnwxAWXi2+GyNByApxnf_DtP1-6+_zOKAdJKnJBexjg@mail.gmail.com/ Link: https://lore.kernel.org/bpf/20230315171550.1551603-1-deso@posteo.net
2023-03-10libbpf: Revert poisoning of strlcpyJesus Sanchez-Palencia
This reverts commit 6d0c4b11e743("libbpf: Poison strlcpy()"). It added the pragma poison directive to libbpf_internal.h to protect against accidental usage of strlcpy but ended up breaking the build for toolchains based on libcs which provide the strlcpy() declaration from string.h (e.g. uClibc-ng). The include order which causes the issue is: string.h, from Iibbpf_common.h:12, from libbpf.h:20, from libbpf_internal.h:26, from strset.c:9: Fixes: 6d0c4b11e743 ("libbpf: Poison strlcpy()") Signed-off-by: Jesus Sanchez-Palencia <jesussanp@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20230309004836.2808610-1-jesussanp@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-07libbpf: USDT arm arg parsing supportPuranjay Mohan
Parsing of USDT arguments is architecture-specific; on arm it is relatively easy since registers used are r[0-10], fp, ip, sp, lr, pc. Format is slightly different compared to aarch64; forms are - "size @ [ reg, #offset ]" for dereferences, for example "-8 @ [ sp, #76 ]" ; " -4 @ [ sp ]" - "size @ reg" for register values; for example "-4@r0" - "size @ #value" for raw values; for example "-8@#1" Add support for parsing USDT arguments for ARM architecture. To test the above changes QEMU's virt[1] board with cortex-a15 CPU was used. libbpf-bootstrap's usdt example[2] was modified to attach to a test program with DTRACE_PROBE1/2/3/4... probes to test different combinations. [1] https://www.qemu.org/docs/master/system/arm/virt.html [2] https://github.com/libbpf/libbpf-bootstrap/blob/master/examples/c/usdt.bpf.c Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230307120440.25941-3-puranjay12@gmail.com
2023-03-07libbpf: Refactor parse_usdt_arg() to re-use codePuranjay Mohan
The parse_usdt_arg() function is defined differently for each architecture but the last part of the function is repeated verbatim for each architecture. Refactor parse_usdt_arg() to fill the arg_sz and then do the repeated post-processing in parse_usdt_spec(). Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230307120440.25941-2-puranjay12@gmail.com
2023-03-07libbpf: Fix theoretical u32 underflow in find_cd() functionDaniel Müller
Coverity reported a potential underflow of the offset variable used in the find_cd() function. Switch to using a signed 64 bit integer for the representation of offset to make sure we can never underflow. Fixes: 1eebcb60633f ("libbpf: Implement basic zip archive parsing support") Signed-off-by: Daniel Müller <deso@posteo.net> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230307215504.837321-1-deso@posteo.net
2023-03-06libbpf: Add support to set kprobe/uprobe attach modeMenglong Dong
By default, libbpf will attach the kprobe/uprobe BPF program in the latest mode that supported by kernel. In this patch, we add the support to let users manually attach kprobe/uprobe in legacy or perf mode. There are 3 mode that supported by the kernel to attach kprobe/uprobe: LEGACY: create perf event in legacy way and don't use bpf_link PERF: create perf event with perf_event_open() and don't use bpf_link Signed-off-by: Menglong Dong <imagedong@tencent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Biao Jiang <benbjiang@tencent.com> Link: create perf event with perf_event_open() and use bpf_link Link: https://lore.kernel.org/bpf/20230113093427.1666466-1-imagedong@tencent.com/ Link: https://lore.kernel.org/bpf/20230306064833.7932-2-imagedong@tencent.com Users now can manually choose the mode with bpf_program__attach_uprobe_opts()/bpf_program__attach_kprobe_opts().
2023-03-03bpf: Rename __kptr_ref -> __kptr and __kptr -> __kptr_untrusted.Alexei Starovoitov
__kptr meant to store PTR_UNTRUSTED kernel pointers inside bpf maps. The concept felt useful, but didn't get much traction, since bpf_rdonly_cast() was added soon after and bpf programs received a simpler way to access PTR_UNTRUSTED kernel pointers without going through restrictive __kptr usage. Rename __kptr_ref -> __kptr and __kptr -> __kptr_untrusted to indicate its intended usage. The main goal of __kptr_untrusted was to read/write such pointers directly while bpf_kptr_xchg was a mechanism to access refcnted kernel pointers. The next patch will allow RCU protected __kptr access with direct read. At that point __kptr_untrusted will be deprecated. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/bpf/20230303041446.3630-2-alexei.starovoitov@gmail.com
2023-03-01libbpf: Add support for attaching uprobes to shared objects in APKsDaniel Müller
This change adds support for attaching uprobes to shared objects located in APKs, which is relevant for Android systems where various libraries may reside in APKs. To make that happen, we extend the syntax for the "binary path" argument to attach to with that supported by various Android tools: <archive>!/<binary-in-archive> For example: /system/app/test-app/test-app.apk!/lib/arm64-v8a/libc++_shared.so APKs need to be specified via full path, i.e., we do not attempt to resolve mere file names by searching system directories. We cannot currently test this functionality end-to-end in an automated fashion, because it relies on an Android system being present, but there is no support for that in CI. I have tested the functionality manually, by creating a libbpf program containing a uretprobe, attaching it to a function inside a shared object inside an APK, and verifying the sanity of the returned values. Signed-off-by: Daniel Müller <deso@posteo.net> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230301212308.1839139-4-deso@posteo.net
2023-03-01libbpf: Introduce elf_find_func_offset_from_file() functionDaniel Müller
This change splits the elf_find_func_offset() function in two: elf_find_func_offset(), which now accepts an already opened Elf object instead of a path to a file that is to be opened, as well as elf_find_func_offset_from_file(), which opens a binary based on a path and then invokes elf_find_func_offset() on the Elf object. Having this split in responsibilities will allow us to call elf_find_func_offset() from other code paths on Elf objects that did not necessarily come from a file on disk. Signed-off-by: Daniel Müller <deso@posteo.net> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230301212308.1839139-3-deso@posteo.net
2023-03-01libbpf: Implement basic zip archive parsing supportDaniel Müller
This change implements support for reading zip archives, including opening an archive, finding an entry based on its path and name in it, and closing it. The code was copied from https://github.com/iovisor/bcc/pull/4440, which implements similar functionality for bcc. The author confirmed that he is fine with this usage and the corresponding relicensing. I adjusted it to adhere to libbpf coding standards. Signed-off-by: Daniel Müller <deso@posteo.net> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Michał Gregorczyk <michalgr@meta.com> Link: https://lore.kernel.org/bpf/20230301212308.1839139-2-deso@posteo.net
2023-03-01libbpf: Cleanup linker_append_elf_relosViktor Malik
Clang Static Analyser (scan-build) reports some unused symbols and dead assignments in the linker_append_elf_relos function. Clean these up. Signed-off-by: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/c5c8fe9f411b69afada8399d23bb048ef2a70535.1677658777.git.vmalik@redhat.com
2023-03-01libbpf: Remove several dead assignmentsViktor Malik
Clang Static Analyzer (scan-build) reports several dead assignments in libbpf where the assigned value is unconditionally overridden by another value before it is read. Remove these assignments. Signed-off-by: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/5503d18966583e55158471ebbb2f67374b11bf5e.1677658777.git.vmalik@redhat.com
2023-03-01libbpf: Remove unnecessary ternary operatorViktor Malik
Coverity reports that the first check of 'err' in bpf_object__init_maps is always false as 'err' is initialized to 0 at that point. Remove the unnecessary ternary operator. Signed-off-by: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/78a3702f2ea9f32a84faaae9b674c56269d330a7.1677658777.git.vmalik@redhat.com
2023-02-27libbpf: Fix bpf_xdp_query() in old kernelsYonghong Song
Commit 04d58f1b26a4("libbpf: add API to get XDP/XSK supported features") added feature_flags to struct bpf_xdp_query_opts. If a user uses bpf_xdp_query_opts with feature_flags member, the bpf_xdp_query() will check whether 'netdev' family exists or not in the kernel. If it does not exist, the bpf_xdp_query() will return -ENOENT. But 'netdev' family does not exist in old kernels as it is introduced in the same patch set as Commit 04d58f1b26a4. So old kernel with newer libbpf won't work properly with bpf_xdp_query() api call. To fix this issue, if the return value of libbpf_netlink_resolve_genl_family_id() is -ENOENT, bpf_xdp_query() will just return 0, skipping the rest of xdp feature query. This preserves backward compatibility. Fixes: 04d58f1b26a4 ("libbpf: add API to get XDP/XSK supported features") Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230227224943.1153459-1-yhs@fb.com
2023-02-27libbpf: Document bpf_{btf,link,map,prog}_get_info_by_fd()Ilya Leoshkevich
Replace the short informal description with the proper doc comments. Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230220234958.764997-1-iii@linux.ibm.com
2023-02-27libbpf: Fix arm syscall regs spec in bpf_tracing.hPuranjay Mohan
The syscall register definitions for ARM in bpf_tracing.h doesn't define the fifth parameter for the syscalls. Because of this some KPROBES based selftests fail to compile for ARM architecture. Define the fifth parameter that is passed in the R5 register (uregs[4]). Fixes: 3a95c42d65d5 ("libbpf: Define arm syscall regs spec in bpf_tracing.h") Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230223095346.10129-1-puranjay12@gmail.com
2023-02-27libbpf: Use struct user_pt_regs to define __PT_REGS_CAST() for LoongArchTiezhu Yang
LoongArch provides struct user_pt_regs instead of struct pt_regs to userspace, use struct user_pt_regs to define __PT_REGS_CAST() to fix the following build error: CLNG-BPF [test_maps] loop1.bpf.o progs/loop1.c:22:9: error: incomplete definition of type 'struct pt_regs' m = PT_REGS_RC(ctx); ^~~~~~~~~~~~~~~ tools/testing/selftests/bpf/tools/include/bpf/bpf_tracing.h:493:41: note: expanded from macro 'PT_REGS_RC' #define PT_REGS_RC(x) (__PT_REGS_CAST(x)->__PT_RC_REG) ~~~~~~~~~~~~~~~~~^ tools/testing/selftests/bpf/tools/include/bpf/bpf_helper_defs.h:20:8: note: forward declaration of 'struct pt_regs' struct pt_regs; ^ 1 error generated. make: *** [Makefile:572: tools/testing/selftests/bpf/loop1.bpf.o] Error 1 make: Leaving directory 'tools/testing/selftests/bpf' Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/1677235015-21717-2-git-send-email-yangtiezhu@loongson.cn
2023-02-16libbpf: Use bpf_{btf,link,map,prog}_get_info_by_fd()Ilya Leoshkevich
Use the new type-safe wrappers around bpf_obj_get_info_by_fd(). Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230214231221.249277-3-iii@linux.ibm.com
2023-02-16libbpf: Introduce bpf_{btf,link,map,prog}_get_info_by_fd()Ilya Leoshkevich
These are type-safe wrappers around bpf_obj_get_info_by_fd(). They found one problem in selftests, and are also useful for adding Memory Sanitizer annotations. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230214231221.249277-2-iii@linux.ibm.com
2023-02-10libbpf: Fix alen calculation in libbpf_nla_dump_errormsg()Ilya Leoshkevich
The code assumes that everything that comes after nlmsgerr are nlattrs. When calculating their size, it does not account for the initial nlmsghdr. This may lead to accessing uninitialized memory. Fixes: bbf48c18ee0c ("libbpf: add error reporting in XDP") Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230210001210.395194-8-iii@linux.ibm.com
2023-02-08libbpf: Add sample_period to creation optionsJon Doron
Add option to set when the perf buffer should wake up, by default the perf buffer becomes signaled for every event that is being pushed to it. In case of a high throughput of events it will be more efficient to wake up only once you have X events ready to be read. So your application can wakeup once and drain the entire perf buffer. Signed-off-by: Jon Doron <jond@wiz.io> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230207081916.3398417-1-arilou@gmail.com
2023-02-07libbpf: Always use libbpf_err to return an error in bpf_xdp_query()Lorenzo Bianconi
In order to properly set errno, rely on libbpf_err utility routine in bpf_xdp_query() to return an error to the caller. Fixes: 04d58f1b26a4 ("libbpf: add API to get XDP/XSK supported features") Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/827d40181f9f90fb37702f44328e1614df7c0503.1675768112.git.lorenzo@kernel.org
2023-02-06libbpf: Correctly set the kernel code version in Debian kernel.Hao Xiang
In a previous commit, Ubuntu kernel code version is correctly set by retrieving the information from /proc/version_signature. commit<5b3d72987701d51bf31823b39db49d10970f5c2d> (libbpf: Improve LINUX_VERSION_CODE detection) The /proc/version_signature file doesn't present in at least the older versions of Debian distributions (eg, Debian 9, 10). The Debian kernel has a similar issue where the release information from uname() syscall doesn't give the kernel code version that matches what the kernel actually expects. Below is an example content from Debian 10. release: 4.19.0-23-amd64 version: #1 SMP Debian 4.19.269-1 (2022-12-20) x86_64 Debian reports incorrect kernel version in utsname::release returned by uname() syscall, which in older kernels (Debian 9, 10) leads to kprobe BPF programs failing to load due to the version check mismatch. Fortunately, the correct kernel code version presents in the utsname::version returned by uname() syscall in Debian kernels. This change adds another get kernel version function to handle Debian in addition to the previously added get kernel version function to handle Ubuntu. Some minor refactoring work is also done to make the code more readable. Signed-off-by: Hao Xiang <hao.xiang@bytedance.com> Signed-off-by: Ho-Ren (Jack) Chuang <horenchuang@bytedance.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230203234842.2933903-1-hao.xiang@bytedance.com
2023-02-02libbpf: add API to get XDP/XSK supported featuresLorenzo Bianconi
Extend bpf_xdp_query routine in order to get XDP/XSK supported features of netdev over route netlink interface. Extend libbpf netlink implementation in order to support netlink_generic protocol. Co-developed-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Co-developed-by: Marek Majtyka <alardam@gmail.com> Signed-off-by: Marek Majtyka <alardam@gmail.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://lore.kernel.org/r/a72609ef4f0de7fee5376c40dbf54ad7f13bfb8d.1675245258.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-02libbpf: add the capability to specify netlink proto in libbpf_netlink_send_recvLorenzo Bianconi
This is a preliminary patch in order to introduce netlink_generic protocol support to libbpf. Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://lore.kernel.org/r/7878a54667e74afeec3ee519999c044bd514b44c.1675245258.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>