Commit d4ecfeb1 authored by Stanislav Fomichev's avatar Stanislav Fomichev Committed by Daniel Borkmann
Browse files

bpf: allow wide aligned loads for bpf_sock_addr user_ip6 and msg_src_ip6 



Add explicit check for u64 loads of user_ip6 and msg_src_ip6 and
update the comment.

Cc: Yonghong Song <yhs@fb.com>
Signed-off-by: default avatarStanislav Fomichev <sdf@google.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
parent b4399546

include/uapi/linux/bpf.h

+2 −2
Original line number Diff line number Diff line
@@ -3248,7 +3248,7 @@ struct bpf_sock_addr { 
	__u32 user_ip4;		/* Allows 1,2,4-byte read and 4-byte write.

				 * Stored in network byte order.

				 */

	__u32 user_ip6[4];	/* Allows 1,2,4-byte read and 4,8-byte write.

	__u32 user_ip6[4];	/* Allows 1,2,4,8-byte read and 4,8-byte write.

				 * Stored in network byte order.

				 */

	__u32 user_port;	/* Allows 4-byte read and write.
@@ -3260,7 +3260,7 @@ struct bpf_sock_addr { 
	__u32 msg_src_ip4;	/* Allows 1,2,4-byte read and 4-byte write.

				 * Stored in network byte order.

				 */

	__u32 msg_src_ip6[4];	/* Allows 1,2,4-byte read and 4,8-byte write.

	__u32 msg_src_ip6[4];	/* Allows 1,2,4,8-byte read and 4,8-byte write.

				 * Stored in network byte order.

				 */

	__bpf_md_ptr(struct bpf_sock *, sk);

net/core/filter.c

+11 −1
Original line number Diff line number Diff line
@@ -6884,9 +6884,19 @@ static bool sock_addr_is_valid_access(int off, int size, 
	case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):

	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],

				msg_src_ip6[3]):

		/* Only narrow read access allowed for now. */

		if (type == BPF_READ) {

			bpf_ctx_record_field_size(info, size_default);



			if (bpf_ctx_wide_access_ok(off, size,

						   struct bpf_sock_addr,

						   user_ip6))

				return true;



			if (bpf_ctx_wide_access_ok(off, size,

						   struct bpf_sock_addr,

						   msg_src_ip6))

				return true;



			if (!bpf_ctx_narrow_access_ok(off, size, size_default))

				return false;

		} else {