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-rw-r--r--kernel/bpf/syscall.c198
1 files changed, 192 insertions, 6 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 43f95d190eea..0244973ee544 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -203,11 +203,13 @@ static int bpf_map_alloc_id(struct bpf_map *map)
{
int id;
+ idr_preload(GFP_KERNEL);
spin_lock_bh(&map_idr_lock);
id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
if (id > 0)
map->id = id;
spin_unlock_bh(&map_idr_lock);
+ idr_preload_end();
if (WARN_ON_ONCE(!id))
return -ENOSPC;
@@ -940,11 +942,13 @@ static int bpf_prog_alloc_id(struct bpf_prog *prog)
{
int id;
+ idr_preload(GFP_KERNEL);
spin_lock_bh(&prog_idr_lock);
id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
if (id > 0)
prog->aux->id = id;
spin_unlock_bh(&prog_idr_lock);
+ idr_preload_end();
/* id is in [1, INT_MAX) */
if (WARN_ON_ONCE(!id))
@@ -1167,8 +1171,75 @@ struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
}
EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
+/* Initially all BPF programs could be loaded w/o specifying
+ * expected_attach_type. Later for some of them specifying expected_attach_type
+ * at load time became required so that program could be validated properly.
+ * Programs of types that are allowed to be loaded both w/ and w/o (for
+ * backward compatibility) expected_attach_type, should have the default attach
+ * type assigned to expected_attach_type for the latter case, so that it can be
+ * validated later at attach time.
+ *
+ * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
+ * prog type requires it but has some attach types that have to be backward
+ * compatible.
+ */
+static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
+{
+ switch (attr->prog_type) {
+ case BPF_PROG_TYPE_CGROUP_SOCK:
+ /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
+ * exist so checking for non-zero is the way to go here.
+ */
+ if (!attr->expected_attach_type)
+ attr->expected_attach_type =
+ BPF_CGROUP_INET_SOCK_CREATE;
+ break;
+ }
+}
+
+static int
+bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
+ enum bpf_attach_type expected_attach_type)
+{
+ switch (prog_type) {
+ case BPF_PROG_TYPE_CGROUP_SOCK:
+ switch (expected_attach_type) {
+ case BPF_CGROUP_INET_SOCK_CREATE:
+ case BPF_CGROUP_INET4_POST_BIND:
+ case BPF_CGROUP_INET6_POST_BIND:
+ return 0;
+ default:
+ return -EINVAL;
+ }
+ case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+ switch (expected_attach_type) {
+ case BPF_CGROUP_INET4_BIND:
+ case BPF_CGROUP_INET6_BIND:
+ case BPF_CGROUP_INET4_CONNECT:
+ case BPF_CGROUP_INET6_CONNECT:
+ return 0;
+ default:
+ return -EINVAL;
+ }
+ default:
+ return 0;
+ }
+}
+
+static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
+ enum bpf_attach_type attach_type)
+{
+ switch (prog->type) {
+ case BPF_PROG_TYPE_CGROUP_SOCK:
+ case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+ return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
+ default:
+ return 0;
+ }
+}
+
/* last field in 'union bpf_attr' used by this command */
-#define BPF_PROG_LOAD_LAST_FIELD prog_ifindex
+#define BPF_PROG_LOAD_LAST_FIELD expected_attach_type
static int bpf_prog_load(union bpf_attr *attr)
{
@@ -1205,11 +1276,17 @@ static int bpf_prog_load(union bpf_attr *attr)
!capable(CAP_SYS_ADMIN))
return -EPERM;
+ bpf_prog_load_fixup_attach_type(attr);
+ if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type))
+ return -EINVAL;
+
/* plain bpf_prog allocation */
prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
if (!prog)
return -ENOMEM;
+ prog->expected_attach_type = attr->expected_attach_type;
+
prog->aux->offload_requested = !!attr->prog_ifindex;
err = security_bpf_prog_alloc(prog->aux);
@@ -1311,11 +1388,87 @@ static int bpf_obj_get(const union bpf_attr *attr)
attr->file_flags);
}
+struct bpf_raw_tracepoint {
+ struct bpf_raw_event_map *btp;
+ struct bpf_prog *prog;
+};
+
+static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
+{
+ struct bpf_raw_tracepoint *raw_tp = filp->private_data;
+
+ if (raw_tp->prog) {
+ bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
+ bpf_prog_put(raw_tp->prog);
+ }
+ kfree(raw_tp);
+ return 0;
+}
+
+static const struct file_operations bpf_raw_tp_fops = {
+ .release = bpf_raw_tracepoint_release,
+ .read = bpf_dummy_read,
+ .write = bpf_dummy_write,
+};
+
+#define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
+
+static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
+{
+ struct bpf_raw_tracepoint *raw_tp;
+ struct bpf_raw_event_map *btp;
+ struct bpf_prog *prog;
+ char tp_name[128];
+ int tp_fd, err;
+
+ if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
+ sizeof(tp_name) - 1) < 0)
+ return -EFAULT;
+ tp_name[sizeof(tp_name) - 1] = 0;
+
+ btp = bpf_find_raw_tracepoint(tp_name);
+ if (!btp)
+ return -ENOENT;
+
+ raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
+ if (!raw_tp)
+ return -ENOMEM;
+ raw_tp->btp = btp;
+
+ prog = bpf_prog_get_type(attr->raw_tracepoint.prog_fd,
+ BPF_PROG_TYPE_RAW_TRACEPOINT);
+ if (IS_ERR(prog)) {
+ err = PTR_ERR(prog);
+ goto out_free_tp;
+ }
+
+ err = bpf_probe_register(raw_tp->btp, prog);
+ if (err)
+ goto out_put_prog;
+
+ raw_tp->prog = prog;
+ tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
+ O_CLOEXEC);
+ if (tp_fd < 0) {
+ bpf_probe_unregister(raw_tp->btp, prog);
+ err = tp_fd;
+ goto out_put_prog;
+ }
+ return tp_fd;
+
+out_put_prog:
+ bpf_prog_put(prog);
+out_free_tp:
+ kfree(raw_tp);
+ return err;
+}
+
#ifdef CONFIG_CGROUP_BPF
#define BPF_PROG_ATTACH_LAST_FIELD attach_flags
-static int sockmap_get_from_fd(const union bpf_attr *attr, bool attach)
+static int sockmap_get_from_fd(const union bpf_attr *attr,
+ int type, bool attach)
{
struct bpf_prog *prog = NULL;
int ufd = attr->target_fd;
@@ -1329,8 +1482,7 @@ static int sockmap_get_from_fd(const union bpf_attr *attr, bool attach)
return PTR_ERR(map);
if (attach) {
- prog = bpf_prog_get_type(attr->attach_bpf_fd,
- BPF_PROG_TYPE_SK_SKB);
+ prog = bpf_prog_get_type(attr->attach_bpf_fd, type);
if (IS_ERR(prog)) {
fdput(f);
return PTR_ERR(prog);
@@ -1374,17 +1526,27 @@ static int bpf_prog_attach(const union bpf_attr *attr)
ptype = BPF_PROG_TYPE_CGROUP_SKB;
break;
case BPF_CGROUP_INET_SOCK_CREATE:
+ case BPF_CGROUP_INET4_POST_BIND:
+ case BPF_CGROUP_INET6_POST_BIND:
ptype = BPF_PROG_TYPE_CGROUP_SOCK;
break;
+ case BPF_CGROUP_INET4_BIND:
+ case BPF_CGROUP_INET6_BIND:
+ case BPF_CGROUP_INET4_CONNECT:
+ case BPF_CGROUP_INET6_CONNECT:
+ ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
+ break;
case BPF_CGROUP_SOCK_OPS:
ptype = BPF_PROG_TYPE_SOCK_OPS;
break;
case BPF_CGROUP_DEVICE:
ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
break;
+ case BPF_SK_MSG_VERDICT:
+ return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, true);
case BPF_SK_SKB_STREAM_PARSER:
case BPF_SK_SKB_STREAM_VERDICT:
- return sockmap_get_from_fd(attr, true);
+ return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_SKB, true);
default:
return -EINVAL;
}
@@ -1393,6 +1555,11 @@ static int bpf_prog_attach(const union bpf_attr *attr)
if (IS_ERR(prog))
return PTR_ERR(prog);
+ if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
+ bpf_prog_put(prog);
+ return -EINVAL;
+ }
+
cgrp = cgroup_get_from_fd(attr->target_fd);
if (IS_ERR(cgrp)) {
bpf_prog_put(prog);
@@ -1429,17 +1596,27 @@ static int bpf_prog_detach(const union bpf_attr *attr)
ptype = BPF_PROG_TYPE_CGROUP_SKB;
break;
case BPF_CGROUP_INET_SOCK_CREATE:
+ case BPF_CGROUP_INET4_POST_BIND:
+ case BPF_CGROUP_INET6_POST_BIND:
ptype = BPF_PROG_TYPE_CGROUP_SOCK;
break;
+ case BPF_CGROUP_INET4_BIND:
+ case BPF_CGROUP_INET6_BIND:
+ case BPF_CGROUP_INET4_CONNECT:
+ case BPF_CGROUP_INET6_CONNECT:
+ ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
+ break;
case BPF_CGROUP_SOCK_OPS:
ptype = BPF_PROG_TYPE_SOCK_OPS;
break;
case BPF_CGROUP_DEVICE:
ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
break;
+ case BPF_SK_MSG_VERDICT:
+ return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, false);
case BPF_SK_SKB_STREAM_PARSER:
case BPF_SK_SKB_STREAM_VERDICT:
- return sockmap_get_from_fd(attr, false);
+ return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_SKB, false);
default:
return -EINVAL;
}
@@ -1478,6 +1655,12 @@ static int bpf_prog_query(const union bpf_attr *attr,
case BPF_CGROUP_INET_INGRESS:
case BPF_CGROUP_INET_EGRESS:
case BPF_CGROUP_INET_SOCK_CREATE:
+ case BPF_CGROUP_INET4_BIND:
+ case BPF_CGROUP_INET6_BIND:
+ case BPF_CGROUP_INET4_POST_BIND:
+ case BPF_CGROUP_INET6_POST_BIND:
+ case BPF_CGROUP_INET4_CONNECT:
+ case BPF_CGROUP_INET6_CONNECT:
case BPF_CGROUP_SOCK_OPS:
case BPF_CGROUP_DEVICE:
break;
@@ -1917,6 +2100,9 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
case BPF_OBJ_GET_INFO_BY_FD:
err = bpf_obj_get_info_by_fd(&attr, uattr);
break;
+ case BPF_RAW_TRACEPOINT_OPEN:
+ err = bpf_raw_tracepoint_open(&attr);
+ break;
default:
err = -EINVAL;
break;
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.