kernel/linux.git/tools/lib/bpf, branch v6.3.6

libbpf: Fix ld_imm64 copy logic for ksym in light skeleton.

2023-05-11T14:17:13+00:00

[ Upstream commit a506d6ce1dd184051037dc9d26c3eb187c9fe625 ] 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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230319203014.55866-1-alexei.starovoitov@gmail.com Signed-off-by: Sasha Levin

libbpf: Fix bpf_xdp_query() in old kernels

2023-05-11T14:17:11+00:00

[ Upstream commit c8ee37bde4021a275d2e4f33bd48d54912bb00c4 ] 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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230227224943.1153459-1-yhs@fb.com Signed-off-by: Sasha Levin

libbpf: Fix arm syscall regs spec in bpf_tracing.h

2023-05-11T14:17:11+00:00

[ Upstream commit 06943ae675945c762bb8d5edc93d203f2b041d8d ] 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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230223095346.10129-1-puranjay12@gmail.com Signed-off-by: Sasha Levin

libbpf: Revert poisoning of strlcpy

2023-03-10T18:19:25+00:00

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 Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20230309004836.2808610-1-jesussanp@google.com Signed-off-by: Alexei Starovoitov

libbpf: Use bpf_{btf,link,map,prog}_get_info_by_fd()

2023-02-16T23:32:45+00:00

Use the new type-safe wrappers around bpf_obj_get_info_by_fd(). Signed-off-by: Ilya Leoshkevich Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230214231221.249277-3-iii@linux.ibm.com

libbpf: Introduce bpf_{btf,link,map,prog}_get_info_by_fd()

2023-02-16T23:32:36+00:00

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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230214231221.249277-2-iii@linux.ibm.com

libbpf: Fix alen calculation in libbpf_nla_dump_errormsg()

2023-02-10T23:27:22+00:00

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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230210001210.395194-8-iii@linux.ibm.com

libbpf: Add sample_period to creation options

2023-02-08T23:27:39+00:00

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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230207081916.3398417-1-arilou@gmail.com

libbpf: Always use libbpf_err to return an error in bpf_xdp_query()

2023-02-07T21:56:11+00:00

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 Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/827d40181f9f90fb37702f44328e1614df7c0503.1675768112.git.lorenzo@kernel.org

libbpf: Correctly set the kernel code version in Debian kernel.

2023-02-06T22:30:50+00:00

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 Signed-off-by: Ho-Ren (Jack) Chuang Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230203234842.2933903-1-hao.xiang@bytedance.com