From: David Howells Date: Wed, 8 Apr 2026 12:12:47 +0000 (+0100) Subject: rxrpc: Fix buffer overread in rxgk_do_verify_authenticator() X-Git-Tag: ceph-for-7.1-rc1~39^2~17^2~2 X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=f564af387c8c28238f8ebc13314c589d7ba8475d;p=ceph-client.git rxrpc: Fix buffer overread in rxgk_do_verify_authenticator() Fix rxgk_do_verify_authenticator() to check the buffer size before checking the nonce. Fixes: 9d1d2b59341f ("rxrpc: rxgk: Implement the yfs-rxgk security class (GSSAPI)") Closes: https://sashiko.dev/#/patchset/20260401105614.1696001-10-dhowells@redhat.com Signed-off-by: David Howells cc: Marc Dionne cc: Jeffrey Altman cc: Simon Horman cc: linux-afs@lists.infradead.org cc: stable@kernel.org Link: https://patch.msgid.link/20260408121252.2249051-20-dhowells@redhat.com Signed-off-by: Jakub Kicinski --- diff --git a/net/rxrpc/rxgk.c b/net/rxrpc/rxgk.c index c67e3c2ca871..0d5e654da918 100644 --- a/net/rxrpc/rxgk.c +++ b/net/rxrpc/rxgk.c @@ -1085,6 +1085,9 @@ static int rxgk_do_verify_authenticator(struct rxrpc_connection *conn, _enter(""); + if ((end - p) * sizeof(__be32) < 24) + return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO, + rxgk_abort_resp_short_auth); if (memcmp(p, conn->rxgk.nonce, 20) != 0) return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO, rxgk_abort_resp_bad_nonce); @@ -1098,7 +1101,7 @@ static int rxgk_do_verify_authenticator(struct rxrpc_connection *conn, p += xdr_round_up(app_len) / sizeof(__be32); if (end - p < 4) return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO, - rxgk_abort_resp_short_applen); + rxgk_abort_resp_short_auth); level = ntohl(*p++); epoch = ntohl(*p++);