summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--include/uapi/linux/bpf.h3
-rw-r--r--kernel/bpf/cgroup.c15
2 files changed, 15 insertions, 3 deletions
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index d01f1cb3cfc0..69eabfcb9bdb 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1012,7 +1012,8 @@ struct bpf_perf_event_value {
#define BPF_DEVCG_DEV_CHAR (1ULL << 1)
struct bpf_cgroup_dev_ctx {
- __u32 access_type; /* (access << 16) | type */
+ /* access_type encoded as (BPF_DEVCG_ACC_* << 16) | BPF_DEVCG_DEV_* */
+ __u32 access_type;
__u32 major;
__u32 minor;
};
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index b789ab78d28f..c1c0b60d3f2f 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -568,6 +568,8 @@ static bool cgroup_dev_is_valid_access(int off, int size,
enum bpf_access_type type,
struct bpf_insn_access_aux *info)
{
+ const int size_default = sizeof(__u32);
+
if (type == BPF_WRITE)
return false;
@@ -576,8 +578,17 @@ static bool cgroup_dev_is_valid_access(int off, int size,
/* The verifier guarantees that size > 0. */
if (off % size != 0)
return false;
- if (size != sizeof(__u32))
- return false;
+
+ switch (off) {
+ case bpf_ctx_range(struct bpf_cgroup_dev_ctx, access_type):
+ bpf_ctx_record_field_size(info, size_default);
+ if (!bpf_ctx_narrow_access_ok(off, size, size_default))
+ return false;
+ break;
+ default:
+ if (size != size_default)
+ return false;
+ }
return true;
}