Files
android_kernel_fxtec_sm6115/net/ceph/auth.c
Raphael Zimmer 7e9639e808 libceph: Fix potential out-of-bounds access in ceph_handle_auth_reply()
commit b282c43ed156ae15ea76748fc15cd5c39dc9ab72 upstream.

This patch fixes an out-of-bounds access in ceph_handle_auth_reply()
that can be triggered by a message of type CEPH_MSG_AUTH_REPLY. In
ceph_handle_auth_reply(), the value of the payload_len field of such a
message is stored in a variable of type int. A value greater than
INT_MAX leads to an integer overflow and is interpreted as a negative
value. This leads to decrementing the pointer address by this value and
subsequently accessing it because ceph_decode_need() only checks that
the memory access does not exceed the end address of the allocation.

This patch fixes the issue by changing the data type of payload_len to
u32. Additionally, the data type of result_msg_len is changed to u32,
as it is also a variable holding a non-negative length.

Also, an additional layer of sanity checks is introduced, ensuring that
directly after reading it from the message, payload_len and
result_msg_len are not greater than the overall segment length.

BUG: KASAN: slab-out-of-bounds in ceph_handle_auth_reply+0x642/0x7a0 [libceph]
Read of size 4 at addr ffff88811404df14 by task kworker/20:1/262

CPU: 20 UID: 0 PID: 262 Comm: kworker/20:1 Not tainted 6.19.2 #5 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: ceph-msgr ceph_con_workfn [libceph]
Call Trace:
 <TASK>
 dump_stack_lvl+0x76/0xa0
 print_report+0xd1/0x620
 ? __pfx__raw_spin_lock_irqsave+0x10/0x10
 ? kasan_complete_mode_report_info+0x72/0x210
 kasan_report+0xe7/0x130
 ? ceph_handle_auth_reply+0x642/0x7a0 [libceph]
 ? ceph_handle_auth_reply+0x642/0x7a0 [libceph]
 __asan_report_load_n_noabort+0xf/0x20
 ceph_handle_auth_reply+0x642/0x7a0 [libceph]
 mon_dispatch+0x973/0x23d0 [libceph]
 ? apparmor_socket_recvmsg+0x6b/0xa0
 ? __pfx_mon_dispatch+0x10/0x10 [libceph]
 ? __kasan_check_write+0x14/0x30i
 ? mutex_unlock+0x7f/0xd0
 ? __pfx_mutex_unlock+0x10/0x10
 ? __pfx_do_recvmsg+0x10/0x10 [libceph]
 ceph_con_process_message+0x1f1/0x650 [libceph]
 process_message+0x1e/0x450 [libceph]
 ceph_con_v2_try_read+0x2e48/0x6c80 [libceph]
 ? __pfx_ceph_con_v2_try_read+0x10/0x10 [libceph]
 ? save_fpregs_to_fpstate+0xb0/0x230
 ? raw_spin_rq_unlock+0x17/0xa0
 ? finish_task_switch.isra.0+0x13b/0x760
 ? __switch_to+0x385/0xda0
 ? __kasan_check_write+0x14/0x30
 ? mutex_lock+0x8d/0xe0
 ? __pfx_mutex_lock+0x10/0x10
 ceph_con_workfn+0x248/0x10c0 [libceph]
 process_one_work+0x629/0xf80
 ? __kasan_check_write+0x14/0x30
 worker_thread+0x87f/0x1570
 ? __pfx__raw_spin_lock_irqsave+0x10/0x10
 ? __pfx_try_to_wake_up+0x10/0x10
 ? kasan_print_address_stack_frame+0x1f7/0x280
 ? __pfx_worker_thread+0x10/0x10
 kthread+0x396/0x830
 ? __pfx__raw_spin_lock_irq+0x10/0x10
 ? __pfx_kthread+0x10/0x10
 ? __kasan_check_write+0x14/0x30
 ? recalc_sigpending+0x180/0x210
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x3f7/0x610
 ? __pfx_ret_from_fork+0x10/0x10
 ? __switch_to+0x385/0xda0
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1a/0x30
 </TASK>

[ idryomov: replace if statements with ceph_decode_need() for
  payload_len and result_msg_len ]

Cc: stable@vger.kernel.org
Signed-off-by: Raphael Zimmer <raphael.zimmer@tu-ilmenau.de>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulrich Hecht <uli@kernel.org>
2026-05-07 10:55:16 +02:00

357 lines
8.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/ceph/ceph_debug.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/ceph/types.h>
#include <linux/ceph/decode.h>
#include <linux/ceph/libceph.h>
#include <linux/ceph/messenger.h>
#include "auth_none.h"
#include "auth_x.h"
/*
* get protocol handler
*/
static u32 supported_protocols[] = {
CEPH_AUTH_NONE,
CEPH_AUTH_CEPHX
};
static int ceph_auth_init_protocol(struct ceph_auth_client *ac, int protocol)
{
switch (protocol) {
case CEPH_AUTH_NONE:
return ceph_auth_none_init(ac);
case CEPH_AUTH_CEPHX:
return ceph_x_init(ac);
default:
return -ENOENT;
}
}
/*
* setup, teardown.
*/
struct ceph_auth_client *ceph_auth_init(const char *name, const struct ceph_crypto_key *key)
{
struct ceph_auth_client *ac;
int ret;
dout("auth_init name '%s'\n", name);
ret = -ENOMEM;
ac = kzalloc(sizeof(*ac), GFP_NOFS);
if (!ac)
goto out;
mutex_init(&ac->mutex);
ac->negotiating = true;
if (name)
ac->name = name;
else
ac->name = CEPH_AUTH_NAME_DEFAULT;
dout("auth_init name %s\n", ac->name);
ac->key = key;
return ac;
out:
return ERR_PTR(ret);
}
void ceph_auth_destroy(struct ceph_auth_client *ac)
{
dout("auth_destroy %p\n", ac);
if (ac->ops)
ac->ops->destroy(ac);
kfree(ac);
}
/*
* Reset occurs when reconnecting to the monitor.
*/
void ceph_auth_reset(struct ceph_auth_client *ac)
{
mutex_lock(&ac->mutex);
dout("auth_reset %p\n", ac);
if (ac->ops && !ac->negotiating)
ac->ops->reset(ac);
ac->negotiating = true;
mutex_unlock(&ac->mutex);
}
/*
* EntityName, not to be confused with entity_name_t
*/
int ceph_auth_entity_name_encode(const char *name, void **p, void *end)
{
int len = strlen(name);
if (*p + 2*sizeof(u32) + len > end)
return -ERANGE;
ceph_encode_32(p, CEPH_ENTITY_TYPE_CLIENT);
ceph_encode_32(p, len);
ceph_encode_copy(p, name, len);
return 0;
}
/*
* Initiate protocol negotiation with monitor. Include entity name
* and list supported protocols.
*/
int ceph_auth_build_hello(struct ceph_auth_client *ac, void *buf, size_t len)
{
struct ceph_mon_request_header *monhdr = buf;
void *p = monhdr + 1, *end = buf + len, *lenp;
int i, num;
int ret;
mutex_lock(&ac->mutex);
dout("auth_build_hello\n");
monhdr->have_version = 0;
monhdr->session_mon = cpu_to_le16(-1);
monhdr->session_mon_tid = 0;
ceph_encode_32(&p, CEPH_AUTH_UNKNOWN); /* no protocol, yet */
lenp = p;
p += sizeof(u32);
ceph_decode_need(&p, end, 1 + sizeof(u32), bad);
ceph_encode_8(&p, 1);
num = ARRAY_SIZE(supported_protocols);
ceph_encode_32(&p, num);
ceph_decode_need(&p, end, num * sizeof(u32), bad);
for (i = 0; i < num; i++)
ceph_encode_32(&p, supported_protocols[i]);
ret = ceph_auth_entity_name_encode(ac->name, &p, end);
if (ret < 0)
goto out;
ceph_decode_need(&p, end, sizeof(u64), bad);
ceph_encode_64(&p, ac->global_id);
ceph_encode_32(&lenp, p - lenp - sizeof(u32));
ret = p - buf;
out:
mutex_unlock(&ac->mutex);
return ret;
bad:
ret = -ERANGE;
goto out;
}
static int ceph_build_auth_request(struct ceph_auth_client *ac,
void *msg_buf, size_t msg_len)
{
struct ceph_mon_request_header *monhdr = msg_buf;
void *p = monhdr + 1;
void *end = msg_buf + msg_len;
int ret;
monhdr->have_version = 0;
monhdr->session_mon = cpu_to_le16(-1);
monhdr->session_mon_tid = 0;
ceph_encode_32(&p, ac->protocol);
ret = ac->ops->build_request(ac, p + sizeof(u32), end);
if (ret < 0) {
pr_err("error %d building auth method %s request\n", ret,
ac->ops->name);
goto out;
}
dout(" built request %d bytes\n", ret);
ceph_encode_32(&p, ret);
ret = p + ret - msg_buf;
out:
return ret;
}
/*
* Handle auth message from monitor.
*/
int ceph_handle_auth_reply(struct ceph_auth_client *ac,
void *buf, size_t len,
void *reply_buf, size_t reply_len)
{
void *p = buf;
void *end = buf + len;
int protocol;
s32 result;
u64 global_id;
void *payload, *payload_end;
u32 payload_len;
char *result_msg;
u32 result_msg_len;
int ret = -EINVAL;
mutex_lock(&ac->mutex);
dout("handle_auth_reply %p %p\n", p, end);
ceph_decode_need(&p, end, sizeof(u32) * 3 + sizeof(u64), bad);
protocol = ceph_decode_32(&p);
result = ceph_decode_32(&p);
global_id = ceph_decode_64(&p);
payload_len = ceph_decode_32(&p);
ceph_decode_need(&p, end, payload_len, bad);
payload = p;
p += payload_len;
ceph_decode_need(&p, end, sizeof(u32), bad);
result_msg_len = ceph_decode_32(&p);
ceph_decode_need(&p, end, result_msg_len, bad);
result_msg = p;
p += result_msg_len;
if (p != end)
goto bad;
dout(" result %d '%.*s' gid %llu len %d\n", result, result_msg_len,
result_msg, global_id, payload_len);
payload_end = payload + payload_len;
if (global_id && ac->global_id != global_id) {
dout(" set global_id %lld -> %lld\n", ac->global_id, global_id);
ac->global_id = global_id;
}
if (ac->negotiating) {
/* server does not support our protocols? */
if (!protocol && result < 0) {
ret = result;
goto out;
}
/* set up (new) protocol handler? */
if (ac->protocol && ac->protocol != protocol) {
ac->ops->destroy(ac);
ac->protocol = 0;
ac->ops = NULL;
}
if (ac->protocol != protocol) {
ret = ceph_auth_init_protocol(ac, protocol);
if (ret) {
pr_err("error %d on auth protocol %d init\n",
ret, protocol);
goto out;
}
}
ac->negotiating = false;
}
ret = ac->ops->handle_reply(ac, result, payload, payload_end);
if (ret == -EAGAIN) {
ret = ceph_build_auth_request(ac, reply_buf, reply_len);
} else if (ret) {
pr_err("auth method '%s' error %d\n", ac->ops->name, ret);
}
out:
mutex_unlock(&ac->mutex);
return ret;
bad:
pr_err("failed to decode auth msg\n");
ret = -EINVAL;
goto out;
}
int ceph_build_auth(struct ceph_auth_client *ac,
void *msg_buf, size_t msg_len)
{
int ret = 0;
mutex_lock(&ac->mutex);
if (ac->ops->should_authenticate(ac))
ret = ceph_build_auth_request(ac, msg_buf, msg_len);
mutex_unlock(&ac->mutex);
return ret;
}
int ceph_auth_is_authenticated(struct ceph_auth_client *ac)
{
int ret = 0;
mutex_lock(&ac->mutex);
if (ac->ops)
ret = ac->ops->is_authenticated(ac);
mutex_unlock(&ac->mutex);
return ret;
}
EXPORT_SYMBOL(ceph_auth_is_authenticated);
int ceph_auth_create_authorizer(struct ceph_auth_client *ac,
int peer_type,
struct ceph_auth_handshake *auth)
{
int ret = 0;
mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->create_authorizer)
ret = ac->ops->create_authorizer(ac, peer_type, auth);
mutex_unlock(&ac->mutex);
return ret;
}
EXPORT_SYMBOL(ceph_auth_create_authorizer);
void ceph_auth_destroy_authorizer(struct ceph_authorizer *a)
{
a->destroy(a);
}
EXPORT_SYMBOL(ceph_auth_destroy_authorizer);
int ceph_auth_update_authorizer(struct ceph_auth_client *ac,
int peer_type,
struct ceph_auth_handshake *a)
{
int ret = 0;
mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->update_authorizer)
ret = ac->ops->update_authorizer(ac, peer_type, a);
mutex_unlock(&ac->mutex);
return ret;
}
EXPORT_SYMBOL(ceph_auth_update_authorizer);
int ceph_auth_add_authorizer_challenge(struct ceph_auth_client *ac,
struct ceph_authorizer *a,
void *challenge_buf,
int challenge_buf_len)
{
int ret = 0;
mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->add_authorizer_challenge)
ret = ac->ops->add_authorizer_challenge(ac, a, challenge_buf,
challenge_buf_len);
mutex_unlock(&ac->mutex);
return ret;
}
EXPORT_SYMBOL(ceph_auth_add_authorizer_challenge);
int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac,
struct ceph_authorizer *a)
{
int ret = 0;
mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->verify_authorizer_reply)
ret = ac->ops->verify_authorizer_reply(ac, a);
mutex_unlock(&ac->mutex);
return ret;
}
EXPORT_SYMBOL(ceph_auth_verify_authorizer_reply);
void ceph_auth_invalidate_authorizer(struct ceph_auth_client *ac, int peer_type)
{
mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->invalidate_authorizer)
ac->ops->invalidate_authorizer(ac, peer_type);
mutex_unlock(&ac->mutex);
}
EXPORT_SYMBOL(ceph_auth_invalidate_authorizer);