kernel.git/tools/bpf/bpftool/net.c, branch linux-6.1.y

bpftool: Fix truncated netlink dumps

2026-03-04T12:20:06Z

[ Upstream commit 3b39d73cc3379360a33eb583b17f21fe55e1288e ] Netlink requires that the recv buffer used during dumps is at least min(PAGE_SIZE, 8k) (see the man page). Otherwise the messages will get truncated. Make sure bpftool follows this requirement, avoid missing information on systems with large pages. Acked-by: Quentin Monnet Fixes: 7084566a236f ("tools/bpftool: Remove libbpf_internal.h usage in bpftool") Signed-off-by: Jakub Kicinski Link: https://lore.kernel.org/r/20260217194150.734701-1-kuba@kernel.org Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin

bpftool: Fix memory leak in dump_xx_nlmsg on realloc failure

2025-08-15T10:04:56Z

[ Upstream commit 99fe8af069a9fa5b09140518b1364e35713a642e ] In function dump_xx_nlmsg(), when realloc() fails to allocate memory, the original pointer to the buffer is overwritten with NULL. This causes a memory leak because the previously allocated buffer becomes unreachable without being freed. Fixes: 7900efc19214 ("tools/bpf: bpftool: improve output format for bpftool net") Signed-off-by: Yuan Chen Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/r/20250620012133.14819-1-chenyuan_fl@163.com Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin

bpftool: use new API for attaching XDP program

2022-01-21T05:22:02Z

Switch to new bpf_xdp_attach() API to avoid deprecation warnings. Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20220120061422.2710637-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov

tools: bpftool: Update and synchronise option list in doc and help msg

2021-07-30T22:40:27Z

All bpftool commands support the options for JSON output and debug from libbpf. In addition, some commands support additional options corresponding to specific use cases. The list of options described in the man pages for the different commands are not always accurate. The messages for interactive help are mostly limited to HELP_SPEC_OPTIONS, and are even less representative of the actual set of options supported for the commands. Let's update the lists: - HELP_SPEC_OPTIONS is modified to contain the "default" options (JSON and debug), and to be extensible (no ending curly bracket). - All commands use HELP_SPEC_OPTIONS in their help message, and then complete the list with their specific options. - The lists of options in the man pages are updated. - The formatting of the list for bpftool.rst is adjusted to match formatting for the other man pages. This is for consistency, and also because it will be helpful in a future patch to automatically check that the files are synchronised. Signed-off-by: Quentin Monnet Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210730215435.7095-5-quentin@isovalent.com

bpftool: Fix a clang compilation warning

2021-04-15T23:50:22Z

With clang compiler: make -j60 LLVM=1 LLVM_IAS=1 <=== compile kernel # build selftests/bpf or bpftool make -j60 -C tools/testing/selftests/bpf LLVM=1 LLVM_IAS=1 make -j60 -C tools/bpf/bpftool LLVM=1 LLVM_IAS=1 the following compilation warning showed up, net.c:160:37: warning: comparison of integers of different signs: '__u32' (aka 'unsigned int') and 'int' [-Wsign-compare] for (nh = (struct nlmsghdr *)buf; NLMSG_OK(nh, len); ^~~~~~~~~~~~~~~~~ .../tools/include/uapi/linux/netlink.h:99:24: note: expanded from macro 'NLMSG_OK' (nlh)->nlmsg_len <= (len)) ~~~~~~~~~~~~~~~~ ^ ~~~ In this particular case, "len" is defined as "int" and (nlh)->nlmsg_len is "unsigned int". The macro NLMSG_OK is defined as below in uapi/linux/netlink.h. #define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \ (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \ (nlh)->nlmsg_len <= (len)) The clang compiler complains the comparision "(nlh)->nlmsg_len <= (len))", but in bpftool/net.c, it is already ensured that "len > 0" must be true. So theoretically the compiler could deduce that comparison of "(nlh)->nlmsg_len" and "len" is okay, but this really depends on compiler internals. Let us add an explicit type conversion (from "int" to "unsigned int") for "len" in NLMSG_OK to silence this warning right now. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210413153435.3029635-1-yhs@fb.com

bpftool: Fix compilation failure for net.o with older glibc

2021-01-06T23:27:38Z

For older glibc ~2.17, #include'ing both linux/if.h and net/if.h fails due to complaints about redefinition of interface flags: CC net.o In file included from net.c:13:0: /usr/include/linux/if.h:71:2: error: redeclaration of enumerator ‘IFF_UP’ IFF_UP = 1<<0, /* sysfs */ ^ /usr/include/net/if.h:44:5: note: previous definition of ‘IFF_UP’ was here IFF_UP = 0x1, /* Interface is up. */ The issue was fixed in kernel headers in [1], but since compilation of net.c picks up system headers the problem can recur. Dropping #include resolves the issue and it is not needed for compilation anyhow. [1] https://lore.kernel.org/netdev/1461512707-23058-1-git-send-email-mikko.rapeli__34748.27880641$1462831734$gmane$org@iki.fi/ Fixes: f6f3bac08ff9 ("tools/bpf: bpftool: add net support") Signed-off-by: Alan Maguire Signed-off-by: Andrii Nakryiko Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/1609948746-15369-1-git-send-email-alan.maguire@oracle.com

tools, bpftool: Add missing close before bpftool net attach exit

2020-11-13T14:59:13Z

progfd is created by prog_parse_fd() in do_attach() and before the latter returns in case of success, the file descriptor should be closed. Fixes: 04949ccc273e ("tools: bpftool: add net attach command to attach XDP on interface") Signed-off-by: Wang Hai Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20201113115152.53178-1-wanghai38@huawei.com

tools/bpftool: Remove libbpf_internal.h usage in bpftool

2020-08-19T01:38:25Z

Most netlink-related functions were unique to bpftool usage, so I moved them into net.c. Few functions are still used by both bpftool and libbpf itself internally, so I've copy-pasted them (libbpf_nl_get_link, libbpf_netlink_open). It's a bit of duplication of code, but better separation of libbpf as a library with public API and bpftool, relying on unexposed functions in libbpf. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200819013607.3607269-3-andriin@fb.com

tools, bpftool: Clean subcommand help messages

2020-06-01T21:38:18Z

This is a clean-up for the formatting of the do_help functions for bpftool's subcommands. The following fixes are included: - Do not use argv[-2] for "iter" help message, as the help is shown by default if no "iter" action is selected, resulting in messages looking like "./bpftool bpftool pin...". - Do not print unused HELP_SPEC_PROGRAM in help message for "bpftool link". - Andrii used argument indexing to avoid having multiple occurrences of bin_name and argv[-2] in the fprintf() for the help message, for "bpftool gen" and "bpftool link". Let's reuse this for all other help functions. We can remove up to thirty arguments for the "bpftool map" help message. - Harmonise all functions, e.g. use ending quotes-comma on a separate line. Signed-off-by: Quentin Monnet Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200523010751.23465-1-quentin@isovalent.com Signed-off-by: Alexei Starovoitov

bpftool: Use consistent include paths for libbpf

2020-01-21T00:37:45Z

Fix bpftool to include libbpf header files with the bpf/ prefix, to be consistent with external users of the library. Also ensure that all includes of exported libbpf header files (those that are exported on 'make install' of the library) use bracketed includes instead of quoted. To make sure no new files are introduced that doesn't include the bpf/ prefix in its include, remove tools/lib/bpf from the include path entirely, and use tools/lib instead. Fixes: 6910d7d3867a ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir") Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/157952560684.1683545.4765181397974997027.stgit@toke.dk