From de7342228b7343774d6a9981c2ddbfb5e201044b Mon Sep 17 00:00:00 2001 From: Rong Tao Date: Sat, 4 Oct 2025 22:23:29 +0800 Subject: bpf: Finish constification of 1st parameter of bpf_d_path() The commit 1b8abbb12128 ("bpf...d_path(): constify path argument") constified the first parameter of the bpf_d_path(), but failed to update it in all places. Finish constification. Otherwise the selftest fail to build: .../selftests/bpf/bpf_experimental.h:222:12: error: conflicting types for 'bpf_path_d_path' 222 | extern int bpf_path_d_path(const struct path *path, char *buf, size_t buf__sz) __ksym; | ^ .../selftests/bpf/tools/include/vmlinux.h:153922:12: note: previous declaration is here 153922 | extern int bpf_path_d_path(struct path *path, char *buf, size_t buf__sz) __weak __ksym; Fixes: 1b8abbb12128 ("bpf...d_path(): constify path argument") Signed-off-by: Rong Tao Signed-off-by: Alexei Starovoitov --- tools/include/uapi/linux/bpf.h | 2 +- tools/testing/selftests/bpf/progs/verifier_vfs_accept.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'tools') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index ae83d8649ef1..6829936d33f5 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -4891,7 +4891,7 @@ union bpf_attr { * * **-ENOENT** if the bpf_local_storage cannot be found. * - * long bpf_d_path(struct path *path, char *buf, u32 sz) + * long bpf_d_path(const struct path *path, char *buf, u32 sz) * Description * Return full path for given **struct path** object, which * needs to be the kernel BTF *path* object. The path is diff --git a/tools/testing/selftests/bpf/progs/verifier_vfs_accept.c b/tools/testing/selftests/bpf/progs/verifier_vfs_accept.c index 3e2d76ee8050..55398c04290a 100644 --- a/tools/testing/selftests/bpf/progs/verifier_vfs_accept.c +++ b/tools/testing/selftests/bpf/progs/verifier_vfs_accept.c @@ -70,7 +70,7 @@ __success int BPF_PROG(path_d_path_from_file_argument, struct file *file) { int ret; - struct path *path; + const struct path *path; /* The f_path member is a path which is embedded directly within a * file. Therefore, a pointer to such embedded members are still -- cgit v1.2.3 From 4d920ed684392ae064af62957d6f5a90312dfaf6 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 5 Oct 2025 18:20:37 -0700 Subject: libbpf: Fix undefined behavior in {get,put}_unaligned_be32() These violate aliasing rules and may be miscompiled unless -fno-strict-aliasing is used. Replace them with the standard memcpy() solution. Note that compilers know how to optimize this properly. Fixes: 4a1c9e544b8d ("libbpf: remove linux/unaligned.h dependency for libbpf_sha256()") Signed-off-by: Eric Biggers Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20251006012037.159295-1-ebiggers@kernel.org --- tools/lib/bpf/libbpf_utils.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) (limited to 'tools') diff --git a/tools/lib/bpf/libbpf_utils.c b/tools/lib/bpf/libbpf_utils.c index 5d66bc6ff098..ac3beae54cf6 100644 --- a/tools/lib/bpf/libbpf_utils.c +++ b/tools/lib/bpf/libbpf_utils.c @@ -148,16 +148,20 @@ const char *libbpf_errstr(int err) } } -#pragma GCC diagnostic push -#pragma GCC diagnostic ignored "-Wpacked" -#pragma GCC diagnostic ignored "-Wattributes" -struct __packed_u32 { __u32 __val; } __attribute__((packed)); -#pragma GCC diagnostic pop - -#define get_unaligned_be32(p) be32_to_cpu((((struct __packed_u32 *)(p))->__val)) -#define put_unaligned_be32(v, p) do { \ - ((struct __packed_u32 *)(p))->__val = cpu_to_be32(v); \ -} while (0) +static inline __u32 get_unaligned_be32(const void *p) +{ + __be32 val; + + memcpy(&val, p, sizeof(val)); + return be32_to_cpu(val); +} + +static inline void put_unaligned_be32(__u32 val, void *p) +{ + __be32 be_val = cpu_to_be32(val); + + memcpy(p, &be_val, sizeof(be_val)); +} #define SHA256_BLOCK_LENGTH 64 #define Ch(x, y, z) (((x) & (y)) ^ (~(x) & (z))) -- cgit v1.2.3 From accb9a7e87f096a12eb21256107b9c8e343f8019 Mon Sep 17 00:00:00 2001 From: KaFai Wan Date: Wed, 8 Oct 2025 18:26:27 +0800 Subject: selftests/bpf: Add test for unpinning htab with internal timer struct Add test to verify that unpinning hash tables containing internal timer structures does not trigger context warnings. Each subtest (timer_prealloc and timer_no_prealloc) can trigger the context warning when unpinning, but the warning cannot be triggered twice within a short time interval (a HZ), which is expected behavior. Signed-off-by: KaFai Wan Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20251008102628.808045-3-kafai.wan@linux.dev Signed-off-by: Alexei Starovoitov --- .../selftests/bpf/prog_tests/pinning_htab.c | 36 ++++++++++++++++++++++ .../selftests/bpf/progs/test_pinning_htab.c | 25 +++++++++++++++ 2 files changed, 61 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/pinning_htab.c create mode 100644 tools/testing/selftests/bpf/progs/test_pinning_htab.c (limited to 'tools') diff --git a/tools/testing/selftests/bpf/prog_tests/pinning_htab.c b/tools/testing/selftests/bpf/prog_tests/pinning_htab.c new file mode 100644 index 000000000000..16bd74be3dbe --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/pinning_htab.c @@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include "test_pinning_htab.skel.h" + +static void unpin_map(const char *map_name, const char *pin_path) +{ + struct test_pinning_htab *skel; + struct bpf_map *map; + int err; + + skel = test_pinning_htab__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel open_and_load")) + return; + + map = bpf_object__find_map_by_name(skel->obj, map_name); + if (!ASSERT_OK_PTR(map, "bpf_object__find_map_by_name")) + goto out; + + err = bpf_map__pin(map, pin_path); + if (!ASSERT_OK(err, "bpf_map__pin")) + goto out; + + err = bpf_map__unpin(map, pin_path); + ASSERT_OK(err, "bpf_map__unpin"); +out: + test_pinning_htab__destroy(skel); +} + +void test_pinning_htab(void) +{ + if (test__start_subtest("timer_prealloc")) + unpin_map("timer_prealloc", "/sys/fs/bpf/timer_prealloc"); + if (test__start_subtest("timer_no_prealloc")) + unpin_map("timer_no_prealloc", "/sys/fs/bpf/timer_no_prealloc"); +} diff --git a/tools/testing/selftests/bpf/progs/test_pinning_htab.c b/tools/testing/selftests/bpf/progs/test_pinning_htab.c new file mode 100644 index 000000000000..ae227930c73c --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_pinning_htab.c @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "vmlinux.h" +#include + +char _license[] SEC("license") = "GPL"; + +struct timer_val { + struct bpf_timer timer; +}; + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __type(key, __u32); + __type(value, struct timer_val); + __uint(max_entries, 1); +} timer_prealloc SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __type(key, __u32); + __type(value, struct timer_val); + __uint(max_entries, 1); + __uint(map_flags, BPF_F_NO_PREALLOC); +} timer_no_prealloc SEC(".maps"); -- cgit v1.2.3