From: Namjae Jeon linkinjeon@kernel.org
mainline inclusion from mainline-v6.4-rc1 commit 30210947a343b6b3ca13adc9bfc88e1543e16dd5 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I74FJA CVE: CVE-2023-32254
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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There is UAF issue under cocurrent smb2 tree disconnect. This patch introduce TREE_CONN_EXPIRE flags for tcon to avoid cocurrent access.
Cc: stable@vger.kernel.org Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-20592 Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: ZhaoLong Wang wangzhaolong1@huawei.com --- fs/ksmbd/mgmt/tree_connect.c | 10 +++++++++- fs/ksmbd/mgmt/tree_connect.h | 3 +++ fs/ksmbd/smb2pdu.c | 3 ++- 3 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/fs/ksmbd/mgmt/tree_connect.c b/fs/ksmbd/mgmt/tree_connect.c index dd262daa2c4a..e3f62df65d3a 100644 --- a/fs/ksmbd/mgmt/tree_connect.c +++ b/fs/ksmbd/mgmt/tree_connect.c @@ -95,7 +95,15 @@ int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess, struct ksmbd_tree_connect *ksmbd_tree_conn_lookup(struct ksmbd_session *sess, unsigned int id) { - return xa_load(&sess->tree_conns, id); + struct ksmbd_tree_connect *tcon; + + tcon = xa_load(&sess->tree_conns, id); + if (tcon) { + if (test_bit(TREE_CONN_EXPIRE, &tcon->status)) + tcon = NULL; + } + + return tcon; }
struct ksmbd_share_config *ksmbd_tree_conn_share(struct ksmbd_session *sess, diff --git a/fs/ksmbd/mgmt/tree_connect.h b/fs/ksmbd/mgmt/tree_connect.h index 71e50271dccf..5ef006c7d1cc 100644 --- a/fs/ksmbd/mgmt/tree_connect.h +++ b/fs/ksmbd/mgmt/tree_connect.h @@ -14,6 +14,8 @@ struct ksmbd_share_config; struct ksmbd_user; struct ksmbd_conn;
+#define TREE_CONN_EXPIRE 1 + struct ksmbd_tree_connect { int id;
@@ -25,6 +27,7 @@ struct ksmbd_tree_connect {
int maximal_access; bool posix_extensions; + unsigned long status; };
struct ksmbd_tree_conn_status { diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index 546fed3daa25..d044a0faf9b6 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -2101,11 +2101,12 @@ int smb2_tree_disconnect(struct ksmbd_work *work)
ksmbd_debug(SMB, "request\n");
- if (!tcon) { + if (!tcon || test_and_set_bit(TREE_CONN_EXPIRE, &tcon->status)) { struct smb2_tree_disconnect_req *req = smb2_get_msg(work->request_buf);
ksmbd_debug(SMB, "Invalid tid %d\n", req->hdr.Id.SyncId.TreeId); + rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED; smb2_set_err_rsp(work); return 0;