From 807c86e2ceba8febe79b289d50cd0d5e0b0af917 Mon Sep 17 00:00:00 2001 From: Sage Weil Date: Mon, 15 Mar 2010 15:52:17 -0700 Subject: [PATCH] ceph: fix authenticator buffer size calculation The buffer size was incorrectly calculated for the ceph_x_encrypt() encapsulated ticket blob. Use a helper (with correct arithmetic) and BUG out if we were wrong. Signed-off-by: Sage Weil --- fs/ceph/auth_x.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/fs/ceph/auth_x.c b/fs/ceph/auth_x.c index f0318427b6da..96e7aaa77678 100644 --- a/fs/ceph/auth_x.c +++ b/fs/ceph/auth_x.c @@ -28,6 +28,12 @@ static int ceph_x_is_authenticated(struct ceph_auth_client *ac) return (ac->want_keys & xi->have_keys) == ac->want_keys; } +static int ceph_x_encrypt_buflen(int ilen) +{ + return sizeof(struct ceph_x_encrypt_header) + ilen + 16 + + sizeof(u32); +} + static int ceph_x_encrypt(struct ceph_crypto_key *secret, void *ibuf, int ilen, void *obuf, size_t olen) { @@ -242,7 +248,7 @@ static int ceph_x_build_authorizer(struct ceph_auth_client *ac, struct ceph_x_ticket_handler *th, struct ceph_x_authorizer *au) { - int len; + int maxlen; struct ceph_x_authorize_a *msg_a; struct ceph_x_authorize_b msg_b; void *p, *end; @@ -253,15 +259,15 @@ static int ceph_x_build_authorizer(struct ceph_auth_client *ac, dout("build_authorizer for %s %p\n", ceph_entity_type_name(th->service), au); - len = sizeof(*msg_a) + sizeof(msg_b) + sizeof(u32) + - ticket_blob_len + 16; - dout(" need len %d\n", len); - if (au->buf && au->buf->alloc_len < len) { + maxlen = sizeof(*msg_a) + sizeof(msg_b) + + ceph_x_encrypt_buflen(ticket_blob_len); + dout(" need len %d\n", maxlen); + if (au->buf && au->buf->alloc_len < maxlen) { ceph_buffer_put(au->buf); au->buf = NULL; } if (!au->buf) { - au->buf = ceph_buffer_new(len, GFP_NOFS); + au->buf = ceph_buffer_new(maxlen, GFP_NOFS); if (!au->buf) return -ENOMEM; } @@ -296,6 +302,7 @@ static int ceph_x_build_authorizer(struct ceph_auth_client *ac, au->buf->vec.iov_len = p - au->buf->vec.iov_base; dout(" built authorizer nonce %llx len %d\n", au->nonce, (int)au->buf->vec.iov_len); + BUG_ON(au->buf->vec.iov_len > maxlen); return 0; out_buf: -- 2.30.2