diff options
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/bpf/bpf.c | 35 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf_internal.h | 24 |
2 files changed, 46 insertions, 13 deletions
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index fe4b6ebc9b8f..c09cbb868c9f 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -65,13 +65,22 @@ static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr, return syscall(__NR_bpf, cmd, attr, size); } +static inline int sys_bpf_fd(enum bpf_cmd cmd, union bpf_attr *attr, + unsigned int size) +{ + int fd; + + fd = sys_bpf(cmd, attr, size); + return ensure_good_fd(fd); +} + static inline int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size) { int retries = 5; int fd; do { - fd = sys_bpf(BPF_PROG_LOAD, attr, size); + fd = sys_bpf_fd(BPF_PROG_LOAD, attr, size); } while (fd < 0 && errno == EAGAIN && retries-- > 0); return fd; @@ -104,7 +113,7 @@ int libbpf__bpf_create_map_xattr(const struct bpf_create_map_params *create_attr attr.inner_map_fd = create_attr->inner_map_fd; attr.map_extra = create_attr->map_extra; - fd = sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_MAP_CREATE, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -206,7 +215,7 @@ int bpf_create_map_in_map_node(enum bpf_map_type map_type, const char *name, attr.numa_node = node; } - fd = sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_MAP_CREATE, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -634,7 +643,7 @@ int bpf_obj_get(const char *pathname) memset(&attr, 0, sizeof(attr)); attr.pathname = ptr_to_u64((void *)pathname); - fd = sys_bpf(BPF_OBJ_GET, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_OBJ_GET, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -745,7 +754,7 @@ int bpf_link_create(int prog_fd, int target_fd, break; } proceed: - fd = sys_bpf(BPF_LINK_CREATE, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_LINK_CREATE, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -788,7 +797,7 @@ int bpf_iter_create(int link_fd) memset(&attr, 0, sizeof(attr)); attr.iter_create.link_fd = link_fd; - fd = sys_bpf(BPF_ITER_CREATE, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_ITER_CREATE, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -946,7 +955,7 @@ int bpf_prog_get_fd_by_id(__u32 id) memset(&attr, 0, sizeof(attr)); attr.prog_id = id; - fd = sys_bpf(BPF_PROG_GET_FD_BY_ID, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_PROG_GET_FD_BY_ID, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -958,7 +967,7 @@ int bpf_map_get_fd_by_id(__u32 id) memset(&attr, 0, sizeof(attr)); attr.map_id = id; - fd = sys_bpf(BPF_MAP_GET_FD_BY_ID, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_MAP_GET_FD_BY_ID, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -970,7 +979,7 @@ int bpf_btf_get_fd_by_id(__u32 id) memset(&attr, 0, sizeof(attr)); attr.btf_id = id; - fd = sys_bpf(BPF_BTF_GET_FD_BY_ID, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_BTF_GET_FD_BY_ID, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -982,7 +991,7 @@ int bpf_link_get_fd_by_id(__u32 id) memset(&attr, 0, sizeof(attr)); attr.link_id = id; - fd = sys_bpf(BPF_LINK_GET_FD_BY_ID, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_LINK_GET_FD_BY_ID, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -1013,7 +1022,7 @@ int bpf_raw_tracepoint_open(const char *name, int prog_fd) attr.raw_tracepoint.name = ptr_to_u64(name); attr.raw_tracepoint.prog_fd = prog_fd; - fd = sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr)); return libbpf_err_errno(fd); } @@ -1033,7 +1042,7 @@ retry: attr.btf_log_buf = ptr_to_u64(log_buf); } - fd = sys_bpf(BPF_BTF_LOAD, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_BTF_LOAD, &attr, sizeof(attr)); if (fd < 0 && !do_log && log_buf && log_buf_size) { do_log = true; @@ -1075,7 +1084,7 @@ int bpf_enable_stats(enum bpf_stats_type type) memset(&attr, 0, sizeof(attr)); attr.enable_stats.type = type; - fd = sys_bpf(BPF_ENABLE_STATS, &attr, sizeof(attr)); + fd = sys_bpf_fd(BPF_ENABLE_STATS, &attr, sizeof(attr)); return libbpf_err_errno(fd); } diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index a6dd7e25747f..aeb79e3a8ff9 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -13,6 +13,8 @@ #include <limits.h> #include <errno.h> #include <linux/err.h> +#include <fcntl.h> +#include <unistd.h> #include "libbpf_legacy.h" #include "relo_core.h" @@ -491,4 +493,26 @@ static inline bool is_ldimm64_insn(struct bpf_insn *insn) return insn->code == (BPF_LD | BPF_IMM | BPF_DW); } +/* if fd is stdin, stdout, or stderr, dup to a fd greater than 2 + * Takes ownership of the fd passed in, and closes it if calling + * fcntl(fd, F_DUPFD_CLOEXEC, 3). + */ +static inline int ensure_good_fd(int fd) +{ + int old_fd = fd, saved_errno; + + if (fd < 0) + return fd; + if (fd < 3) { + fd = fcntl(fd, F_DUPFD_CLOEXEC, 3); + saved_errno = errno; + close(old_fd); + if (fd < 0) { + pr_warn("failed to dup FD %d to FD > 2: %d\n", old_fd, -saved_errno); + errno = saved_errno; + } + } + return fd; +} + #endif /* __LIBBPF_LIBBPF_INTERNAL_H */ |