linux-stable.git/net/ceph, branch master

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

2026-05-12T19:00:59+00:00

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

libceph: handle rbtree insertion error in decode_choose_args()

2026-05-12T19:00:58+00:00

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

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

2026-05-11T18:53:53+00:00

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

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

2026-05-11T08:39:22+00:00

In __ceph_x_decrypt(), a part of the buffer p is interpreted as a
ceph_x_encrypt_header, and the magic field of this struct is accessed.
This happens without any guarantee that the buffer is large enough to
hold this struct. The function parameter ciphertext_len represents the
length of the ciphertext to decrypt and is guaranteed to be at most the
remaining size of the allocated buffer p. However, this value is not
necessarily greater than sizeof(ceph_x_encrypt_header). E.g., a message
frame of type FRAME_TAG_AUTH_REPLY_MORE, that is just as long to hold
the ciphertext at its end with a ciphertext_len of 8 or less, can
trigger an out-of-bounds memory access when accessing hdr->magic.

This patch fixes the issue by adding a check to ensure that the
decrypted plaintext in the buffer is large enough to represent at least
the ceph_x_encrypt_header.

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

libceph: Fix unnecessarily high ceph_decode_need() for uniform bucket

2026-05-11T08:39:22+00:00

In crush_decode_uniform_bucket(), the item_weight field of the bucket
is set. This is a single field of type u32 since the uniform bucket uses
the same weight for all items. The value in ceph_decode_need() is set to
(1+b->h.size) * sizeof(u32), which is higher than actually needed.

This patch removes the call to ceph_decode_need() with the unnecessarily
high value and switches the subsequent operation from ceph_decode_32()
to ceph_decode_32_safe(), which already includes the correct bounds
check.

Signed-off-by: Raphael Zimmer 
Reviewed-by: Ilya Dryomov 
Signed-off-by: Ilya Dryomov

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

2026-05-11T08:39:21+00:00

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

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

2026-04-21T23:40:23+00:00

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

crush: cleanup in crush_do_rule() method

2026-04-21T23:40:23+00:00

Commit 41ebcc0907c5 ("crush: remove forcefeed functionality") from
May 7, 2012 (linux-next), leads to the following Smatch static
checker warning:

	net/ceph/crush/mapper.c:1015 crush_do_rule()
	warn: iterator 'j' not incremented

Before commit 41ebcc0907c5 ("crush: remove forcefeed functionality"),
we had this logic:

  j = 0;
  if (osize == 0 && force_pos >= 0) {
      o[osize] = force_context[force_pos];
      if (recurse_to_leaf)
          c[osize] = force_context[0];
      j++;           /* <-- this was the only increment, now gone */
      force_pos--;
  }
  /* then crush_choose_*(..., o+osize, j, ...) */

Now, the variable j is dead code — a variable that is set
and never meaningfully varied. This patch simply removes
the dead code.

Reported-by: Dan Carpenter 
Signed-off-by: Viacheslav Dubeyko 
Reviewed-by: Alex Markuze 
Signed-off-by: Ilya Dryomov

libceph: update outdated comment in ceph_sock_write_space()

2026-04-21T23:40:22+00:00

The function try_write() was renamed to ceph_con_v1_try_write()
in commit 566050e17e53 ("libceph: separate msgr1 protocol
implementation") and subsequently moved to net/ceph/messenger_v1.c
in commit 2f713615ddd9 ("libceph: move msgr1 protocol implementation
to its own file").  Update the comment in ceph_sock_write_space()
accordingly.

[ idryomov: account for msgr2 in the updated comment as well ]

Signed-off-by: kexinsun 
Reviewed-by: Viacheslav Dubeyko 
Signed-off-by: Ilya Dryomov

libceph: Remove obsolete session key alignment logic

2026-04-21T23:40:22+00:00

Since the call to crypto_shash_setkey() was replaced with
hmac_sha256_preparekey() which doesn't allocate memory regardless of the
alignment of the input key, remove the session key alignment logic from
process_auth_done().  Also remove the inclusion of crypto/hash.h, which
is no longer needed since crypto_shash is no longer used.

[ idryomov: rewrap comment ]

Signed-off-by: Eric Biggers 
Reviewed-by: Ilya Dryomov 
Signed-off-by: Ilya Dryomov