| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
lib/ucs2_string.c: fix out-of-bounds read in ucs2_strnlen()
Patch series "lib/ucs2_string.c: fix out-of-bounds read in
ucs2_strnlen()", v2.
This series fixes an off-by-one out-of-bounds read in ucs2_strnlen().
The first patch is the real fix, the second patch comes as a bonus and
fixes the code indentation.
This patch (of 2):
ucs2_strnlen() checks the current character before checking whether the
caller-provided maximum length has been reached. If the input is not
NUL-terminated within that bound, the loop can read one ucs2_char_t past
the limit.
Test the length before dereferencing to prevent an off-by-one
out-of-bounds read. |
| In the Linux kernel, the following vulnerability has been resolved:
media: cec: stm32: prevent out-of-bounds write on RX overflow
stm32_rx_done() appends each received CEC byte to rx_msg.msg[] using
rx_msg.len as the write index, incrementing it on every RXBR
(receive-byte-ready) interrupt without checking it against the buffer
size:
cec->rx_msg.msg[cec->rx_msg.len++] = val & 0xFF;
rx_msg.msg[] is a fixed CEC_MAX_MSG_SIZE (16) byte array in struct
cec_msg, and rx_msg.len is only reset on RXACKE/RXOVR or after a
completed message (RXEND). The number of bytes received before RXEND is
decided by the remote CEC device (it sets EOM), not by the driver. A
peer that keeps sending bytes without ending the message drives RXBR
repeatedly, pushing rx_msg.len past 16 and writing peer-controlled bytes
out of bounds into the surrounding memory. This is reachable in normal
operation once the driver has probed and receiving is enabled, from the
IRQ thread, without any local privilege.
The length check in the CEC core runs on the consumer side, after the
byte has been stored, so it does not prevent the overflow. Bound the
index in the driver before the store, as the other platform CEC drivers
already do (e.g. tegra_cec), dropping the excess bytes of an overlong
frame.
Found by static analysis tool CodeQL. |
| In the Linux kernel, the following vulnerability has been resolved:
media: vicodec: fix out-of-bounds write in FWHT encoder
vidioc_s_fmt_vid_out() sizes the encoder CAPTURE buffer from the
compressed descriptor pixfmt_fwht, whose sizeimage_mult is 3:
coded_w * coded_h * 3 + sizeof(struct fwht_cframe_hdr). fwht_encode_frame()
encodes one plane per component, and an incompressible plane takes the
FWHT_FRAME_UNENCODED path in encode_plane(), copying the plane verbatim.
For a 4-component pixel format all four planes are full resolution
(width_div == height_div == 1), so a frame that forces every plane
through the unencoded fallback writes
sizeof(struct fwht_cframe_hdr) + 4 * coded_w * coded_h bytes, overrunning
the plane by coded_w * coded_h, which can result in corruption
of adjacent kernel heap memory.
Bump pixfmt_fwht.sizeimage_mult from 3 to 4, matching the largest
components_num among the supported raw formats, so the capture buffer is
always large enough for the unencoded fallback. |
| In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix slab-out-of-bounds in nilfs_direct_propagate after truncation
Shuangpeng Bai reported that KASAN detected a slab-out-of-bounds error
in nilfs_direct_propagate() during testing.
Analysis revealed that after truncating a file, a node block immediately
below the B-tree root was not deleted. Instead, it remained in the B-tree
node cache in a dirty state. The log writer subsequently detected this
block and incorrectly invoked nilfs_direct_propagate() on it, which is
designed to handle only data blocks in direct mapping.
B-tree nodes in the cache are managed by virtual block numbers, and their
logical keys typically exceed the range expected by direct mapping.
Consequently, processing such a node as a direct mapping entry triggers
a slab-out-of-bounds access.
The root cause is that when a B-tree mapping collapses into a direct
mapping during truncation, an intermediate node block pointed to by the
root node is left behind as garbage instead of being explicitly deleted.
This resolves the issue by adding a nilfs_btree_discard() operation
to delete the remaining intermediate node block during the conversion.
A 'deform' flag is added to the bop_delete interface to explicitly signal
that the deletion is part of a mapping transformation. This allows the
B-tree mapping implementation to perform the necessary cleanup and
discarding of the residual node structure that would be otherwise be left
orphaned after the transition. |
| In the Linux kernel, the following vulnerability has been resolved:
ubifs: fix out-of-bounds read in signature length check
ubifs_sb_verify_signature() bounds the on-disk ubifs_sig_node->len field
before handing the signature payload to verify_pkcs7_signature(), but the
check has the wrong sign:
if (le32_to_cpu(signode->len) > snod->len + sizeof(struct ubifs_sig_node))
The signature bytes start sizeof(struct ubifs_sig_node) (UBIFS_SIG_NODE_SZ,
64 bytes) into the node, so the payload is at most
snod->len - sizeof(struct ubifs_sig_node)
bytes long. Adding the header size instead of subtracting it accepts a
declared length up to 2 * UBIFS_SIG_NODE_SZ larger than the node actually
holds -- past the end of c->sbuf, which is vmalloc(c->leb_size).
verify_pkcs7_signature() -> pkcs7_parse_message() -> asn1_ber_decoder()
is then handed that inflated length and reads beyond the allocation while
walking the DER headers. The node length comes straight from the mounted
image, so a crafted signed UBIFS image reaches this via
ubifs_read_superblock() before the signature is cryptographically checked.
snod->len is guaranteed to be >= UBIFS_SIG_NODE_SZ by the node scanner
(c->ranges[UBIFS_SIG_NODE].min_len == UBIFS_SIG_NODE_SZ), so the corrected
subtraction cannot underflow. Legitimately signed images are unaffected: a
correct superblock never declares a signature longer than the node it is
embedded in. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: restart ssc_expire_umount walk after dropping nfsd_ssc_lock
nfsd4_ssc_expire_umount() walks nn->nfsd_ssc_mount_list with
list_for_each_entry_safe(ni, tmp, ...). For each expired entry it
sets nsui_busy = true, drops nfsd_ssc_lock to run mntput() on the
source vfsmount, then reacquires the lock to list_del + kfree the
entry and continue iterating via the macro's saved tmp pointer.
The nsui_busy flag protects the current ni from concurrent
nfsd4_ssc_setup_dul() finders during the lock-drop window, but it
does not pin tmp. Another nfsd RPC thread that fails its source-
server mount and reaches nfsd4_ssc_cancel_dul() will, during that
same window, take nfsd_ssc_lock, list_del + kfree its own ssc_umount
item, and release the lock. If that item is the saved tmp of the
expire walk, the next iteration dereferences a freed
nfsd4_ssc_umount_item.
Restart the walk from the head after the mntput() unlock window so
no saved next pointer survives the lock-drop. The list is bounded
by the number of active inter-server source mounts (typically small)
and the expire delayed-work runs periodically rather than per-IO,
so the restart is cheap. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: remove flawed WARN_ON_ONCE from nfsd_mode_check
The header for commit e75b23f9e323 ("nfsd: check d_can_lookup in
fh_verify of directories") details the assumption that justified
adding the WARN_ON_ONCE to nfsd_mode_check(), that assumption is
invalid (in the case of NFS reexport).
When NFSD exports an NFS filesystem it is very possible for
nfsd_mode_check() to encounter a @dentry that doesn't have
i_op->lookup (see nfs_fhget()'s NFS_ATTR_FATTR_MOUNTPOINT and
NFS_ATTR_FATTR_V4_REFERRAL handling, and d_flags_for_inode()).
So remove nfsd_mode_check()'s WARN_ON_ONCE(). The nfserr_notdir
return on that branch must stay. It guards the subsequent
lookup_one_unlocked() -> __lookup_slow() path, which calls
inode->i_op->lookup() with no NULL check, so returning nfserr_notdir
is what keeps a client LOOKUP into such a @dentry from dereferencing
a NULL method pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSv4.1: fix layout segment leak on the pnfs_layout_process() forget path
When the server returns a new layout stateid while a valid one is still
held, pnfs_layout_process() calls pnfs_mark_matching_lsegs_return() on
the on-stack free_me list and jumps to out_forget. Segments whose
reference count drops to zero are unlinked from lo->plh_segs and moved
to free_me by mark_lseg_invalid(); for an idle cached segment the layout
header holds the only reference, so this happens on the first decrement.
out_forget never drains free_me -- only the success path calls
pnfs_free_lseg_list().
Commit 814b84971388 ("pNFS/NFSv4: Fix a layout segment leak in
pnfs_layout_process()") added the drain; commit 08bd8dbe8882
("pNFS/NFSv4: Try to return invalid layout in pnfs_layout_process()")
removed it while switching the destination to lo->plh_return_segs, which
is drained elsewhere. Commit fb700ef02676 ("NFSv4.1: Simplify layout
return in pnfs_layout_process()") switched the destination back to
free_me without restoring the drain.
Restore the pnfs_free_lseg_list() call. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: Reset write verifier when async COPY writeback fails
Async COPY captures nn->writeverf at request time and reports it to
the client via CB_OFFLOAD after the worker kthread completes. When
the post-copy vfs_fsync_range() or filemap_check_wb_err() in
_nfsd_copy_file_range() reports an error, the worker correctly
leaves NFSD4_COPY_F_COMMITTED clear so that CB_OFFLOAD encodes
wr_stable_how as NFS_UNSTABLE, but the server's write verifier is
not rotated.
A client that receives NFS_UNSTABLE in CB_OFFLOAD follows up with
COMMIT to make the copied data durable. With the verifier
unchanged, COMMIT returns the same value the client just received
via CB_OFFLOAD, and the client concludes the copy is durable --
silently dropping the data whose writeback in fact failed. This
violates the UNSTABLE+COMMIT durability contract (RFC 7862 section
15.1, RFC 8881 section 18.32) and matches the bug just fixed in
nfsd_vfs_write() and nfsd_commit().
Rotate nn->writeverf at the writeback-failure site. The async COPY
worker has no svc_rqst, so commit_reset_write_verifier() is not
available here; calling nfsd_reset_write_verifier() directly
mirrors the trace-less reset already used by
nfsd_file_check_write_error() for the same purpose. Filter out
-EAGAIN and -ESTALE, matching commit_reset_write_verifier(), since
neither indicates a durable-storage failure. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: sample writeback error cursor before async COPY loop
_nfsd_copy_file_range() samples dst->f_wb_err into "since"
after the copy loop, then uses it to detect writeback errors
via filemap_check_wb_err() once vfs_fsync_range() returns.
Because the nfsd_file cache reuses a single struct file
across requests targeting the same inode, a concurrent
COMMIT or stable WRITE on dst advances dst->f_wb_err to the
current mapping->wb_err via file_check_and_advance_wb_err()
during its own vfs_fsync_range(). If that advancement lands
between the writeback error appearing in mapping->wb_err
and the COPY worker sampling "since", the worker captures
the already-advanced cursor, errseq_check() sees cur ==
since and returns zero, and NFSD4_COPY_F_COMMITTED is set
even though writeback failed. CB_OFFLOAD then encodes
wr_stable_how = FILE_SYNC4, the client treats the copied
data as durable, and the failure becomes silent data loss.
Sample since once at the start of the function. The cursor
then reflects state in effect before this COPY issues any
writes, and filemap_check_wb_err() detects any error that
occurs during the copy regardless of which thread first
observes it. This matches the pattern used by
nfsd_vfs_write() and nfsd4_clone_file_range(). |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: block non-SAVEFH ops after FOREIGN PUTFH to prevent NULL deref
When CONFIG_NFSD_V4_2_INTER_SSC is enabled, nfsd4_putfh() can return
success with fh_dentry and fh_export both NULL if fh_verify() returns
nfserr_stale and putfh->no_verify is true. The NFSD4_FH_FOREIGN flag
is set, but the compound dispatch loop only uses this flag to bypass
the nfserr_nofilehandle check -- it does not prevent subsequent ops
from running with a NULL fh_dentry.
A remote client can exploit this by crafting a COMPOUND that includes
an inter-SSC COPY (which causes check_if_stalefh_allowed() to set
no_verify=true on the saved PUTFH) with an additional op inserted
between the source PUTFH and SAVEFH. For example, SETATTR calls
fh_want_write() which dereferences fh_export->ex_path.mnt without
calling fh_verify() first, causing a NULL pointer dereference in the
nfsd kthread.
Fix this by gating the dispatch loop: when NFSD4_FH_FOREIGN is set
and fh_dentry is NULL, only OP_SAVEFH (needed for the inter-SSC flow)
and ops with ALLOWED_WITHOUT_FH (which don't need a resolved
filehandle) may proceed. All other ops receive nfserr_stale, per
RFC 7862 Section 15.2.3 which specifies that foreign filehandle
validation is deferred to the consuming operation and NFS4ERR_STALE
returned at that point. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: check client ownership when cancelling a copy-notify stateid
On the OFFLOAD_CANCEL path (clp != NULL), manage_cpntf_state() freed the
target cpntf state without checking ownership. The lookup key
st->si_opaque.so_id is allocated cyclically (guessable) and the embedded
clientid is the fixed per-net nn->s2s_cp_cl_id, so any authenticated
NFSv4.2 client could cancel and free another client's copy-notify
stateid.
Compare the creating clientid recorded in state->cp_p_clid against the
requesting client's cl_clientid and return nfserr_bad_stateid on a
mismatch instead of freeing the entry. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix cpntf publish race in nfs4_init_cp_state
nfs4_alloc_init_cpntf_state() published the new cpntf entry into the
s2s_cp_stateids IDR (with cs_type set) in one s2s_cp_lock section, then
took the lock again to list_add() it onto p_stid->sc_cp_list. In the gap
the entry is reachable by so_id but cp_list is still {NULL,NULL} from
kzalloc. A racing OFFLOAD_CANCEL (so_id is echoed to the client as
cnr_stateid, so any NFSv4.2 client can drive it) reaches
manage_cpntf_state() -> _free_cpntf_state_locked() and does list_del() on
the zeroed list_head, oopsing the server.
Fold the cs_type assignment and the list_add() into the same critical
section as idr_alloc_cyclic(), so a concurrent lookup either misses the
entry or sees a fully linked cp_list. INIT_LIST_HEAD() the entry after
allocation and switch _free_cpntf_state_locked() to list_del_init() so a
stale unlink is a no-op. nfs4_init_copy_state() passes NULL p_stid and
skips the list_add, preserving NFS4_COPY_STID semantics. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix XDR length calculation in nfsd4_ff_encode_layoutget
The XDR buffer size calculation in nfsd4_ff_encode_layoutget() has
multiple errors that can result in either an out-of-bounds write or
leaking uninitialized kernel memory to the client:
- fh_len doesn't account for XDR padding on the file handle data
- uid and gid lengths use "8 + len" but xdr_encode_opaque() actually
writes "4 + xdr_align_size(len)" bytes
- ds_len omits the flags and stats_collect_hint fields (8 bytes),
while len's header constant overestimates by 8 bytes -- these
partially cancel but leave a net mismatch
The worst case occurs with short strings (e.g. uid=0, gid=0 with an
odd-sized file handle), where the function writes up to 5 bytes past
the reserved XDR buffer. Conversely, when string lengths happen to be
4-byte aligned, the reservation is too large and stale buffer content
is sent to the client.
Fix this by breaking out every encoded field explicitly in the ds_len
calculation, using xdr_align_size() for all variable-length opaque
fields, and correcting the header constants. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo
nfsd4_ff_encode_getdeviceinfo() computes the da_addr_body reservation
as 16 + netid_len + addr_len, but the subsequent xdr_encode_opaque()
calls emit 8 + round_up(netid_len, 4) + round_up(addr_len, 4) bytes.
The mismatch means the declared da_addr_body length exceeds the actual
encoded data by 2-8 bytes on every flexfile GETDEVICEINFO reply,
leaking stale reply-page content to the client and mis-aligning the
subsequent version list decode.
Use xdr_align_size() for each string length to match what
xdr_encode_opaque() actually writes. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: initialize copy-notify stateid before publishing it
nfsd4_copy_notify() finished initializing the cpntf state after
nfs4_alloc_init_cpntf_state() had already linked it into the
s2s_cp_stateids IDR and the parent's sc_cp_list, with cs_count == 1 (the
membership reference) and none held for the caller. A racing
OFFLOAD_CANCEL (crafted cl_id == nn->s2s_cp_cl_id plus the guessable
so_id) could reach manage_cpntf_state() and free the entry, turning the
caller's subsequent cpn_cnr_stateid read and cp_p_stateid/cp_p_clid
writes into use-after-free. The owning clientid was also only recorded
after publication, so it could not gate an ownership check in that window.
Record cp_p_stateid and cp_p_clid inside nfs4_alloc_init_cpntf_state()
before nfs4_init_cp_state() publishes the entry, and return it with an
extra reference. The caller reads the stateid under that reference and
drops it with nfs4_put_cpntf_state(); on a late error the laundromat
reaps the entry. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: revoke copy-notify stateids before dropping their reference
Copy-notify stateids live in the s2s_cp_stateids IDR and on their parent
stid's sc_cp_list, pinned by a single membership reference.
_free_cpntf_state_locked() only unlinks an entry once its refcount reaches
zero, so any revoke path that runs while a concurrent
find_cpntf_state()/manage_cpntf_state() holder has elevated cs_count drops
the reference without unlinking, leaving the entry discoverable with its
membership reference already consumed. A second revoke or a laundromat tick
then frees it while the reader still holds the pointer -- a
KASAN-detectable use-after-free at the reader's nfs4_put_cpntf_state().
This affected all three revoke paths:
- The parent-stid drain (nfs4_free_cpntf_statelist()) repeatedly called
_free_cpntf_state_locked() on the first list entry; a holder that had
bumped cs_count made it return early, so the next iteration
re-decremented and burned the holder's reference.
- OFFLOAD_CANCEL (manage_cpntf_state()) and laundromat expiry likewise
used _free_cpntf_state_locked() and could drop 2->1 without unlinking.
Add revoke_cpntf_state_locked(), which unhashes the entry from the IDR and
sc_cp_list first (deferring the final free to any holder), and use it from
all three revoke paths. The drain now walks with list_for_each_entry_safe()
and revokes each entry unconditionally, so it terminates in one pass per
entry regardless of cs_count. The unhash is gated on
!list_empty(&cps->cp_list); the idr_remove() gate matters because
idr_alloc_cyclic() may have recycled the so_id by then. Keep
_free_cpntf_state_locked() for the reference-holder put path only, where a
concurrent revoke may already have unlinked the entry (its list_del_init()
then a no-op). |
| In the Linux kernel, the following vulnerability has been resolved:
libceph: validate OSD extent maps before cursor advance
net/ceph/osd_client.c:osd_sparse_read() validates that the sparse-read
data length matches the summed extent lengths, but it does not validate
that each OSD-supplied extent is monotonic and lies inside the original
request range. A malformed authenticated OSD reply can advertise a
far-forward nonzero extent offset with a matching data length and make
the client advance the message-data cursor beyond the request buffer.
This reaches the BUG_ON(!*length) assertion in ceph_msg_data_next() from
the client receive path.
Impact: A malicious or compromised authenticated Ceph OSD peer can crash
a kernel Ceph client via a malformed sparse-read reply.
Reject sparse extent maps that overflow, move backwards, overlap, or
extend outside the original sparse-read request before advancing the
cursor.
[ idryomov: perform sparse_extent_map_valid() check a bit earlier,
in CEPH_SPARSE_READ_DATA_LEN instead of CEPH_SPARSE_READ_DATA_PRE
state ] |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix ALIGN() overflow in symlink_data() error context loop
The check added by commit 7d9a7f1f96cd ("smb/client: fix possible
infinite loop and oob read in symlink_data()") compared the post-ALIGN
length against the remaining buffer, but ALIGN() itself can overflow:
for ErrorDataLength near UINT32_MAX (e.g. 0xFFFFFFF9), ALIGN(x, 8)
wraps to 0, so the subsequent bounds check passes, and the loop
advances by zero bytes leaving 'p' pointing into stale data.
Fix by checking the raw ErrorDataLength against the remaining space
before applying ALIGN(), then checking again after. Since raw_len is
bounded by the buffer, raw_len + 7 cannot overflow, so the second check
is an exact post-alignment bounds guard. |
| In the Linux kernel, the following vulnerability has been resolved:
HID: picolcd: clamp eeprom debugfs read to bytes actually received
picolcd_debug_eeprom_read() trusts resp->raw_data[2] -- a length byte
supplied by the device in its REPORT_EE_DATA reply -- clamped only to
the caller's read() count:
ret = resp->raw_data[2];
if (ret > s)
ret = s;
if (copy_to_user(u, resp->raw_data+3, ret))
It never checks resp->raw_size, the number of bytes picolcd_raw_event()
actually copied into the 64-byte raw_data[] of the kmalloc'd struct
picolcd_pending. A device (or a spoofed picoLCD) returning a length byte
of 0xff, read with a count >= 255, makes copy_to_user() read past
raw_data[] into adjacent slab memory and return it to userspace through
the debugfs "eeprom" file:
BUG: KASAN: slab-out-of-bounds in _copy_to_user
Read of size 255 ... picolcd_debug_eeprom_read+0x214/0x2f0 [hid_picolcd]
The debug-dump path in the same file already validates the device length
byte against the received size before trusting it; this read does not.
The file is created S_IRUSR (root-only) and a crafted device is needed,
so it is neither unprivileged- nor remotely-triggerable.
Clamp the copy length to resp->raw_size - 3 (the payload actually
received, minus the 3-byte header), floored at 0 for short replies. |
