Add BPF_F_TOKEN_FD flag to be used across bpf() syscall commands that accept BPF token FD: BPF_PROG_LOAD, BPF_MAP_CREATE, and BPF_BTF_LOAD. This flag has to be set whenever token FD is provided. BPF_BTF_LOAD command didn't have a flags field, so add it as well. Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx> --- include/uapi/linux/bpf.h | 10 +++++++--- kernel/bpf/syscall.c | 19 +++++++++++++++---- tools/include/uapi/linux/bpf.h | 10 +++++++--- 3 files changed, 29 insertions(+), 10 deletions(-) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index e0545201b55f..539dc19d8d11 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1364,6 +1364,9 @@ enum { /* Get path from provided FD in BPF_OBJ_PIN/BPF_OBJ_GET commands */ BPF_F_PATH_FD = (1U << 14), + +/* BPF token FD is passed in a corresponding command's token_fd field */ + BPF_F_TOKEN_FD = (1U << 15), }; /* Flags for BPF_PROG_QUERY. */ @@ -1437,7 +1440,7 @@ union bpf_attr { * to using 5 hash functions). */ __u64 map_extra; - __u32 map_token_fd; + __s32 map_token_fd; }; struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */ @@ -1507,7 +1510,7 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 log_true_size; - __u32 prog_token_fd; + __s32 prog_token_fd; }; struct { /* anonymous struct used by BPF_OBJ_* commands */ @@ -1620,7 +1623,8 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 btf_log_true_size; - __u32 btf_token_fd; + __u32 btf_flags; + __s32 btf_token_fd; }; struct { diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 8faa1a20edf8..d6337842006d 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1137,6 +1137,7 @@ static int map_create(union bpf_attr *attr) int numa_node = bpf_map_attr_numa_node(attr); u32 map_type = attr->map_type; struct bpf_map *map; + bool token_flag; int f_flags; int err; @@ -1144,6 +1145,12 @@ static int map_create(union bpf_attr *attr) if (err) return -EINVAL; + /* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it + * to avoid per-map type checks tripping on unknown flag + */ + token_flag = attr->map_flags & BPF_F_TOKEN_FD; + attr->map_flags &= ~BPF_F_TOKEN_FD; + if (attr->btf_vmlinux_value_type_id) { if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || attr->btf_key_type_id || attr->btf_value_type_id) @@ -1184,7 +1191,7 @@ static int map_create(union bpf_attr *attr) if (!ops->map_mem_usage) return -EINVAL; - if (attr->map_token_fd) { + if (token_flag) { token = bpf_token_get_from_fd(attr->map_token_fd); if (IS_ERR(token)) return PTR_ERR(token); @@ -2641,12 +2648,13 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) BPF_F_TEST_RND_HI32 | BPF_F_XDP_HAS_FRAGS | BPF_F_XDP_DEV_BOUND_ONLY | - BPF_F_TEST_REG_INVARIANTS)) + BPF_F_TEST_REG_INVARIANTS | + BPF_F_TOKEN_FD)) return -EINVAL; bpf_prog_load_fixup_attach_type(attr); - if (attr->prog_token_fd) { + if (attr->prog_flags & BPF_F_TOKEN_FD) { token = bpf_token_get_from_fd(attr->prog_token_fd); if (IS_ERR(token)) return PTR_ERR(token); @@ -4837,7 +4845,10 @@ static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_ if (CHECK_ATTR(BPF_BTF_LOAD)) return -EINVAL; - if (attr->btf_token_fd) { + if (attr->btf_flags & ~BPF_F_TOKEN_FD) + return -EINVAL; + + if (attr->btf_flags & BPF_F_TOKEN_FD) { token = bpf_token_get_from_fd(attr->btf_token_fd); if (IS_ERR(token)) return PTR_ERR(token); diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index e0545201b55f..539dc19d8d11 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1364,6 +1364,9 @@ enum { /* Get path from provided FD in BPF_OBJ_PIN/BPF_OBJ_GET commands */ BPF_F_PATH_FD = (1U << 14), + +/* BPF token FD is passed in a corresponding command's token_fd field */ + BPF_F_TOKEN_FD = (1U << 15), }; /* Flags for BPF_PROG_QUERY. */ @@ -1437,7 +1440,7 @@ union bpf_attr { * to using 5 hash functions). */ __u64 map_extra; - __u32 map_token_fd; + __s32 map_token_fd; }; struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */ @@ -1507,7 +1510,7 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 log_true_size; - __u32 prog_token_fd; + __s32 prog_token_fd; }; struct { /* anonymous struct used by BPF_OBJ_* commands */ @@ -1620,7 +1623,8 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 btf_log_true_size; - __u32 btf_token_fd; + __u32 btf_flags; + __s32 btf_token_fd; }; struct { -- 2.34.1