linux-stable.git/net/ceph, branch linux-6.18.y

libceph: handle rbtree insertion error in decode_choose_args()

2026-05-23T11:07:19+00:00

commit d289478cfc0bcf81c7914200d6abdcb78bd04ded upstream.

A message of type CEPH_MSG_OSD_MAP contains an OSD map that itself
contains a CRUSH map. The received CRUSH map may optionally contain
choose_args that get decoded in decode_choose_args(). In this function,
num_choose_arg_maps is read from the message, and a corresponding number
of crush_choose_arg_maps gets decoded afterwards. Each
crush_choose_arg_map has a choose_args_index, which serves as the key
when inserting it into the choose_args rbtree of the decoded crush_map.
If a (potentially corrupted) message contains two crush_choose_arg_maps
with the same index, the assertion in insert_choose_arg_map() triggers a
kernel BUG when trying to insert the second crush_choose_arg_map.

This patch fixes the issue by switching to the non-asserting rbtree
insertion function and rejecting the message if the insertion fails.

[ idryomov: changelog ]

Cc: stable@vger.kernel.org
Signed-off-by: Raphael Zimmer 
Reviewed-by: Ilya Dryomov 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

libceph: Fix potential out-of-bounds access in crush_decode()

2026-05-23T11:07:19+00:00

commit 4c79fc2d598694bda845b46229c9d48b65042970 upstream.

A message of type CEPH_MSG_OSD_MAP containing a crush map with at least
one bucket has two fields holding the bucket algorithm. If the values
in these two fields differ, an out-of-bounds access can occur. This is
the case because the first algorithm field (alg) is used to allocate
the correct amount of memory for a bucket of this type, while the second
algorithm field inside the bucket (b->alg) is used in the subsequent
processing.

This patch fixes the issue by adding a check that compares alg and
b->alg and aborts the processing in case they differ. Furthermore,
b->alg is set to 0 in this case, because the destruction of the crush
map also uses this field to determine the bucket type, which can again
result in an out-of-bounds access when trying to free the memory pointed
to by the fields of the bucket. To correctly free the memory allocated
for the bucket in such a case, the corresponding call to kfree is moved
from the algorithm-specific crush_destroy_bucket functions to the
generic crush_destroy_bucket().

Cc: stable@vger.kernel.org
Signed-off-by: Raphael Zimmer 
Reviewed-by: Ilya Dryomov 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

libceph: Fix potential null-ptr-deref in decode_choose_args()

2026-05-23T11:07:19+00:00

commit 28b0a2ab8c82d0bbdeb8013029c67c978ce6e4bf upstream.

A message of type CEPH_MSG_OSD_MAP contains an OSD map that itself
contains a CRUSH map. When decoding this CRUSH map in crush_decode(), an
array of max_buckets CRUSH buckets is decoded, where some indices may
not refer to actual buckets and are therefore set to NULL. The received
CRUSH map may optionally contain choose_args that get decoded in
decode_choose_args(). When decoding a crush_choose_arg_map, a series of
choose_args for different buckets is decoded, with the bucket_index
being read from the incoming message. It is only checked that the bucket
index does not exceed max_buckets, but not that it doesn't point to an
index with a NULL bucket. If a (potentially corrupted) message contains
a crush_choose_arg_map including such a bucket_index, a null pointer
dereference may occur in the subsequent processing when attempting to
access the bucket with the given index.

This patch fixes the issue by extending the affected check. Now, it is
only attempted to access the bucket if it is not NULL.

Cc: stable@vger.kernel.org
Signed-off-by: Raphael Zimmer 
Reviewed-by: Ilya Dryomov 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

libceph: Fix potential out-of-bounds access in osdmap_decode()

2026-05-23T11:07:19+00:00

commit 35d0ed82d03e5ee77ea4f31f20e29562a7721649 upstream.

When decoding osd_state and osd_weight from an incoming osdmap in
osdmap_decode(), both are decoded for each osd, i.e., map->max_osd
times. The ceph_decode_need() check only accounts for
sizeof(*map->osd_weight) once. This can potentially result in an
out-of-bounds memory access if the incoming message is corrupted such
that the max_osd value exceeds the actual content of the osdmap message.

This patch fixes the issue by changing the corresponding part in the
ceph_decode_need() check to account for
map->max_osd*sizeof(*map->osd_weight).

Cc: stable@vger.kernel.org
Fixes: dcbc919a5dc8 ("libceph: switch osdmap decoding to use ceph_decode_entity_addr")
Signed-off-by: Raphael Zimmer 
Reviewed-by: Ilya Dryomov 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

libceph: Fix slab-out-of-bounds access in auth message processing

2026-05-14T13:30:20+00:00

commit 1c439de70b1c3eb3c6bffa8245c16b9fc318f114 upstream.

If a (potentially corrupted) message of type CEPH_MSG_AUTH_REPLY
contains a positive value in its result field, it is treated as an
error code by ceph_handle_auth_reply() and returned to
handle_auth_reply(). Thereafter, an attempt is made to send the
preallocated message of type CEPH_MSG_AUTH, where the returned value is
interpreted as the size of the front segment to send. If the result
value in the message is greater than the size of the memory buffer
allocated for the front segment, an out-of-bounds access occurs, and
the content of the memory region beyond this buffer is sent out.

This patch fixes the issue by treating only negative values in the
result field as errors. Positive values are therefore treated as success
in the same way as a zero value. Additionally, a BUG_ON is added to
__send_prepared_auth_request() comparing the len parameter to
front_alloc_len to prevent sending the message if it exceeds the bounds
of the allocation and to make it easier to catch any logic flaws leading
to this.

Cc: stable@vger.kernel.org
Signed-off-by: Raphael Zimmer 
Reviewed-by: Ilya Dryomov 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

libceph: Prevent potential null-ptr-deref in ceph_handle_auth_reply()

2026-05-07T04:11:46+00:00

commit 5199c125d25aeae8615c4fc31652cc0fe624338e upstream.

If a message of type CEPH_MSG_AUTH_REPLY contains a zero value for both
protocol and result, this is currently not treated as an error. In case
of ac->negotiating == true and ac->protocol > 0, this leads to setting
ac->protocol = 0 and ac->ops = NULL. Thereafter, the check for
ac->protocol != protocol returns false, and init_protocol() is not
called. Subsequently, ac->ops->handle_reply() is called, which leads to
a null pointer dereference, because ac->ops is still NULL.

This patch changes the check for ac->protocol != protocol to
!ac->protocol, as this also includes the case when the protocol was set
to zero in the message. This causes the message to be treated as
containing a bad auth protocol.

Cc: stable@vger.kernel.org
Signed-off-by: Raphael Zimmer 
Reviewed-by: Ilya Dryomov 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

libceph: admit message frames only in CEPH_CON_S_OPEN state

2026-03-19T15:08:30+00:00

commit a5a373705081d7cc6363e16990e2361b0b362314 upstream.

Similar checks are performed for all control frames, but an early check
for message frames was missing.  process_message() is already set up to
terminate the loop in case the state changes while con->ops->dispatch()
handler is being executed.

Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov 
Reviewed-by: Alex Markuze 
Reviewed-by: Viacheslav Dubeyko 
Signed-off-by: Greg Kroah-Hartman

libceph: Use u32 for non-negative values in ceph_monmap_decode()

2026-03-19T15:08:30+00:00

commit 770444611f047dbfd4517ec0bc1b179d40c2f346 upstream.

This patch fixes unnecessary implicit conversions that change signedness
of blob_len and num_mon in ceph_monmap_decode().
Currently blob_len and num_mon are (signed) int variables. They are used
to hold values that are always non-negative and get assigned in
ceph_decode_32_safe(), which is meant to assign u32 values. Both
variables are subsequently used as unsigned values, and the value of
num_mon is further assigned to monmap->num_mon, which is of type u32.
Therefore, both variables should be of type u32. This is especially
relevant for num_mon. If the value read from the incoming message is
very large, it is interpreted as a negative value, and the check for
num_mon > CEPH_MAX_MON does not catch it. This leads to the attempt to
allocate a very large chunk of memory for monmap, which will most likely
fail. In this case, an unnecessary attempt to allocate memory is
performed, and -ENOMEM is returned instead of -EINVAL.

Cc: stable@vger.kernel.org
Signed-off-by: Raphael Zimmer 
Reviewed-by: Viacheslav Dubeyko 
Reviewed-by: Ilya Dryomov 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

libceph: prevent potential out-of-bounds reads in process_message_header()

2026-03-19T15:08:30+00:00

commit 69fb5d91bba44ecf7eb80530b85fa4fb028921d5 upstream.

If the message frame is (maliciously) corrupted in a way that the
length of the control segment ends up being less than the size of the
message header or a different frame is made to look like a message
frame, out-of-bounds reads may ensue in process_message_header().

Perform an explicit bounds check before decoding the message header.

Cc: stable@vger.kernel.org
Reported-by: Raphael Zimmer 
Signed-off-by: Ilya Dryomov 
Reviewed-by: Alex Markuze 
Reviewed-by: Viacheslav Dubeyko 
Signed-off-by: Greg Kroah-Hartman

libceph: reject preamble if control segment is empty

2026-03-19T15:08:30+00:00

commit c4c22b846eceff05b1129b8844a80310e55a7f87 upstream.

While head_onwire_len() has a branch to handle ctrl_len == 0 case,
prepare_read_control() always sets up a kvec for the CRC meaning that
a non-empty control segment is effectively assumed.  All frames that
clients deal with meet that assumption, so let's make it official and
treat the preamble with an empty control segment as malformed.

Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov 
Reviewed-by: Alex Markuze 
Signed-off-by: Greg Kroah-Hartman