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| author | Andrii Nakryiko <andrii@kernel.org> | 2023-06-13 15:35:33 -0700 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2023-06-19 14:04:04 +0200 |
| commit | 7f6719f7a8662a40afed367a685516f9f34e7bc2 (patch) | |
| tree | caa644c43993c20faef1d7446b79625e9ed2c941 /kernel/bpf | |
| parent | 6c3eba1c5e283fd2bb1c076dbfcb47f569c3bfde (diff) | |
| download | linux-7f6719f7a8662a40afed367a685516f9f34e7bc2.tar.gz linux-7f6719f7a8662a40afed367a685516f9f34e7bc2.tar.bz2 linux-7f6719f7a8662a40afed367a685516f9f34e7bc2.zip | |
bpf: Keep BPF_PROG_LOAD permission checks clear of validations
Move out flags validation and license checks out of the permission
checks. They were intermingled, which makes subsequent changes harder.
Clean this up: perform straightforward flag validation upfront, and
fetch and check license later, right where we use it. Also consolidate
capabilities check in one block, right after basic attribute sanity
checks.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20230613223533.3689589-5-andrii@kernel.org
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/syscall.c | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 658d1154f221..a75c54b6f8a3 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2550,7 +2550,6 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) struct btf *attach_btf = NULL; int err; char license[128]; - bool is_gpl; if (CHECK_ATTR(BPF_PROG_LOAD)) return -EINVAL; @@ -2569,16 +2568,6 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) !bpf_capable()) return -EPERM; - /* copy eBPF program license from user space */ - if (strncpy_from_bpfptr(license, - make_bpfptr(attr->license, uattr.is_kernel), - sizeof(license) - 1) < 0) - return -EFAULT; - license[sizeof(license) - 1] = 0; - - /* eBPF programs must be GPL compatible to use GPL-ed functions */ - is_gpl = license_is_gpl_compatible(license); - /* Intent here is for unprivileged_bpf_disabled to block BPF program * creation for unprivileged users; other actions depend * on fd availability and access to bpffs, so are dependent on @@ -2671,12 +2660,20 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) make_bpfptr(attr->insns, uattr.is_kernel), bpf_prog_insn_size(prog)) != 0) goto free_prog_sec; + /* copy eBPF program license from user space */ + if (strncpy_from_bpfptr(license, + make_bpfptr(attr->license, uattr.is_kernel), + sizeof(license) - 1) < 0) + goto free_prog_sec; + license[sizeof(license) - 1] = 0; + + /* eBPF programs must be GPL compatible to use GPL-ed functions */ + prog->gpl_compatible = license_is_gpl_compatible(license) ? 1 : 0; prog->orig_prog = NULL; prog->jited = 0; atomic64_set(&prog->aux->refcnt, 1); - prog->gpl_compatible = is_gpl ? 1 : 0; if (bpf_prog_is_dev_bound(prog->aux)) { err = bpf_prog_dev_bound_init(prog, attr); |