From 1b275bd49e58752efb83767a5d1aed41356c5e64 Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Fri, 4 Jul 2025 16:30:50 +0200 Subject: [PATCH] libceph: define and enforce CEPH_MAX_KEY_LEN [ Upstream commit ac431d597a9bdfc2ba6b314813f29a6ef2b4a3bf ] When decoding the key, verify that the key material would fit into a fixed-size buffer in process_auth_done() and generally has a sane length. The new CEPH_MAX_KEY_LEN check replaces the existing check for a key with no key material which is a) not universal since CEPH_CRYPTO_NONE has to be excluded and b) doesn't provide much value since a smaller than needed key is just as invalid as no key -- this has to be handled elsewhere anyway. Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin --- net/ceph/crypto.c | 8 +++++--- net/ceph/crypto.h | 2 +- net/ceph/messenger_v2.c | 2 +- 3 files changed, 7 insertions(+), 5 deletions(-) diff --git a/net/ceph/crypto.c b/net/ceph/crypto.c index 051d22c0e4ad..3397d105f74f 100644 --- a/net/ceph/crypto.c +++ b/net/ceph/crypto.c @@ -37,9 +37,6 @@ static int set_secret(struct ceph_crypto_key *key, void *buf) return -ENOTSUPP; } - if (!key->len) - return -EINVAL; - key->key = kmemdup(buf, key->len, GFP_NOIO); if (!key->key) { ret = -ENOMEM; @@ -95,6 +92,11 @@ int ceph_crypto_key_decode(struct ceph_crypto_key *key, void **p, void *end) ceph_decode_copy(p, &key->created, sizeof(key->created)); key->len = ceph_decode_16(p); ceph_decode_need(p, end, key->len, bad); + if (key->len > CEPH_MAX_KEY_LEN) { + pr_err("secret too big %d\n", key->len); + return -EINVAL; + } + ret = set_secret(key, *p); memzero_explicit(*p, key->len); *p += key->len; diff --git a/net/ceph/crypto.h b/net/ceph/crypto.h index 13bd526349fa..0d32f1649f3d 100644 --- a/net/ceph/crypto.h +++ b/net/ceph/crypto.h @@ -5,7 +5,7 @@ #include #include -#define CEPH_KEY_LEN 16 +#define CEPH_MAX_KEY_LEN 16 #define CEPH_MAX_CON_SECRET_LEN 64 /* diff --git a/net/ceph/messenger_v2.c b/net/ceph/messenger_v2.c index f163283abc4e..83c29714226f 100644 --- a/net/ceph/messenger_v2.c +++ b/net/ceph/messenger_v2.c @@ -2389,7 +2389,7 @@ bad: */ static int process_auth_done(struct ceph_connection *con, void *p, void *end) { - u8 session_key_buf[CEPH_KEY_LEN + 16]; + u8 session_key_buf[CEPH_MAX_KEY_LEN + 16]; u8 con_secret_buf[CEPH_MAX_CON_SECRET_LEN + 16]; u8 *session_key = PTR_ALIGN(&session_key_buf[0], 16); u8 *con_secret = PTR_ALIGN(&con_secret_buf[0], 16);