kernel/git/stable/linux.git/tools/lib/bpf/xsk.c, branch master

libbpf: move xsk.{c,h} into selftests/bpf

2022-06-28T20:13:32+00:00

Remove deprecated xsk APIs from libbpf. But given we have selftests relying on this, move those files (with minimal adjustments to make them compilable) under selftests/bpf. We also remove all the removed APIs from libbpf.map, while overall keeping version inheritance chain, as most APIs are backwards compatible so there is no need to reassign them as LIBBPF_1.0.0 versions. Cc: Magnus Karlsson Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20220627211527.2245459-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov

libbpf: Fix array_size.cocci warning

2022-03-08T06:13:00+00:00

Fix the following coccicheck warning: tools/lib/bpf/bpf.c:114:31-32: WARNING: Use ARRAY_SIZE tools/lib/bpf/xsk.c:484:34-35: WARNING: Use ARRAY_SIZE tools/lib/bpf/xsk.c:485:35-36: WARNING: Use ARRAY_SIZE It has been tested with gcc (Debian 8.3.0-6) 8.3.0 on x86_64. Signed-off-by: Guo Zhengkui Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220306023426.19324-1-guozhengkui@vivo.com

libbpf: Unmap rings when umem deleted

2022-03-08T05:56:54+00:00

xsk_umem__create() does mmap for fill/comp rings, but xsk_umem__delete() doesn't do the unmap. This works fine for regular cases, because xsk_socket__delete() does unmap for the rings. But for the case that xsk_socket__create_shared() fails, umem rings are not unmapped. fill_save/comp_save are checked to determine if rings have already be unmapped by xsk. If fill_save and comp_save are NULL, it means that the rings have already been used by xsk. Then they are supposed to be unmapped by xsk_socket__delete(). Otherwise, xsk_umem__delete() does the unmap. Fixes: 2f6324a3937f ("libbpf: Support shared umems between queues and devices") Signed-off-by: Cheng Li Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220301132623.GA19995@vscode.7~

libbpf: Add sane strncpy alternative and use it internally

2021-12-14T14:47:56+00:00

strncpy() has a notoriously error-prone semantics which makes GCC complain about it a lot (and quite often completely completely falsely at that). Instead of pleasing GCC all the time (-Wno-stringop-truncation is unfortunately only supported by GCC, so it's a bit too messy to just enable it in Makefile), add libbpf-internal libbpf_strlcpy() helper which follows what FreeBSD's strlcpy() does and what most people would expect from strncpy(): copies up to N-1 first bytes from source string into destination string and ensures zero-termination afterwards. Replace all the relevant uses of strncpy/strncat/memcpy in libbpf with libbpf_strlcpy(). This also fixes the issue reported by Emmanuel Deloget in xsk.c where memcpy() could access source string beyond its end. Fixes: 2f6324a3937f8 (libbpf: Support shared umems between queues and devices) Reported-by: Emmanuel Deloget Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20211211004043.2374068-1-andrii@kernel.org

libbpf: Prevent deprecation warnings in xsk.c

2021-11-25T22:35:46+00:00

xsk.c is using own APIs that are marked for deprecation internally. Given xsk.c and xsk.h will be gone in libbpf 1.0, there is no reason to do public vs internal function split just to avoid deprecation warnings. So just add a pragma to silence deprecation warnings (until the code is removed completely). Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20211124193233.3115996-4-andrii@kernel.org

libbpf: Use bpf_map_create() consistently internally

2021-11-25T22:35:46+00:00

Remove all the remaining uses of to-be-deprecated bpf_create_map*() APIs. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20211124193233.3115996-3-andrii@kernel.org

libbpf: Remove internal use of deprecated bpf_prog_load() variants

2021-11-07T16:34:23+00:00

Remove all the internal uses of bpf_load_program_xattr(), which is slated for deprecation in v0.7. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211103220845.2676888-5-andrii@kernel.org

libbpf: Use O_CLOEXEC uniformly when opening fds

2021-10-28T23:30:07+00:00

There are some instances where we don't use O_CLOEXEC when opening an fd, fix these up. Otherwise, it is possible that a parallel fork causes these fds to leak into a child process on execve. Signed-off-by: Kumar Kartikeya Dwivedi Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211028063501.2239335-6-memxor@gmail.com

libbpf: Fix build with latest gcc/binutils with LTO

2021-09-08T02:32:04+00:00

After updating to binutils 2.35, the build began to fail with an assembler error. A bug was opened on the Red Hat Bugzilla a few days later for the same issue. Work around the problem by using the new `symver` attribute (introduced in GCC 10) as needed instead of assembler directives. This addresses Red Hat ([0]) and OpenSUSE ([1]) bug reports, as well as libbpf issue ([2]). [0]: https://bugzilla.redhat.com/show_bug.cgi?id=1863059 [1]: https://bugzilla.opensuse.org/show_bug.cgi?id=1188749 [2]: Closes: https://github.com/libbpf/libbpf/issues/338 Co-developed-by: Patrick McCarty Co-developed-by: Michal Suchanek Signed-off-by: Patrick McCarty Signed-off-by: Michal Suchanek Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20210907221023.2660953-1-andrii@kernel.org

libbpf: Fixes incorrect rx_ring_setup_done

2021-06-08T00:44:03+00:00

When calling xsk_socket__create_shared(), the logic at line 1097 marks a boolean flag true within the xsk_umem structure to track setup progress in order to support multiple calls to the function. However, instead of marking umem->tx_ring_setup_done, the code incorrectly sets umem->rx_ring_setup_done. This leads to improper behaviour when creating and destroying xsk and umem structures. Multiple calls to this function is documented as supported. Fixes: ca7a83e2487a ("libbpf: Only create rx and tx XDP rings when necessary") Signed-off-by: Kev Jackson Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/YL4aU4f3Aaik7CN0@linux-dev