| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: ADD_ADDR rtx: free sk if last
When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer(),
and released at the end.
If at that moment, it was the last reference being held, the sk would
not be freed. sock_put() should then be called instead of __sock_put().
But that's not enough: if it is the last reference, sock_put() will call
sk_free(), which will end up calling sk_stop_timer_sync() on the same
timer, and waiting indefinitely to finish. So it is needed to mark that
the timer is done at the end of the timer handler when it has not been
rescheduled, not to call sk_stop_timer_sync() on "itself". |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: ADD_ADDR rtx: always decrease sk refcount
When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer().
It should then be released in all cases at the end.
Some (unlikely) checks were returning directly instead of calling
sock_put() to decrease the refcount. Jump to a new 'exit' label to call
__sock_put() (which will become sock_put() in the next commit) to fix
this potential leak.
While at it, drop the '!msk' check which cannot happen because it is
never reset, and explicitly mark the remaining one as "unlikely". |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: clear CALLBACK_RUNNING on failed delegation recall queue
nfsd_break_one_deleg() sets NFSD4_CALLBACK_RUNNING via test_and_set_bit
at entry to serialize recall work, then calls nfsd4_run_cb() to queue
the recall. When the queue attempt fails the refcount bump is undone,
but the RUNNING bit is left set. The only site that clears the bit is
nfsd41_destroy_cb() (fs/nfsd/nfs4callback.c), which runs from the
workqueue and is therefore unreachable when nothing was queued.
The bit becomes a permanent latch on dp->dl_recall.cb_flags: every
subsequent break_lease() on the same delegation hits the early-return
guard in nfsd_break_one_deleg() and silently skips the recall, so the
delegation is never broken and the conflicting open or lock stalls.
Fix by clearing NFSD4_CALLBACK_RUNNING on the !queued branch alongside
the refcount_dec. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: release OPEN-decoded posix ACLs via op_release
nfsd4_decode_createhow4() calls nfsd4_decode_fattr4(), which allocates
refcounted struct posix_acl objects via posix_acl_alloc() and stores
them in open->op_pacl and open->op_dpacl. These pointers must be
released once the OPEN compound finishes.
When nfsd4_decode_open_claim4() returns a non-seqid-mutating error,
the dispatcher short-circuits before op_func runs:
nfsd4_proc_compound()
if (op->status && op->opnum == OP_OPEN)
op->status = nfsd4_open_omfg(...)
if (!seqid_mutating_err(ntohl(op->status)))
return op->status; /* nfsd4_open() never runs */
...
opdesc->op_release(&op->u) /* must still release op_pacl/op_dpacl */
Before this change OP_OPEN had no .op_release in nfsd4_ops[], and the
release pair lived inside nfsd4_open() at its out_err: label. On the
short-circuit path nfsd4_open() is never invoked, so both posix_acl
refs leak on every malformed OPEN compound that carries valid POSIX
ACL createhow4 attributes.
Add nfsd4_open_release() and wire it as .op_release for OP_OPEN.
posix_acl_release() is NULL-safe, so the single release site covers
both the normal path and the nfsd4_open_omfg short-circuit. Remove
the matching posix_acl_release() pair from nfsd4_open()'s out_err:
label to avoid double-releasing.
The compound loop has two encoding branches: nfsd4_encode_operation()
for normal ops, and nfsd4_encode_replay() for v4.0 replayed ops.
op_release was only called from nfsd4_encode_operation(), so resources
attached to op->u leak on the replay path.
Move the op_release() call out of nfsd4_encode_operation() and the
replay branch, placing it after the if-else in nfsd4_proc_compound().
This gives a single call site in a fairly obviously-correct place,
covering both the normal encoding and replay paths. |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: fix leaked inode reference on writeback abort at umount
ceph_dirty_folio() takes a wrbuffer claim on each newly dirtied folio: it
bumps i_wrbuffer_ref (taking an ihold() on the 0->1 transition) and
attaches the snap_context to folio->private. That claim is released only
by ceph_put_wrbuffer_cap_refs(), which for a submitted write runs from
writepages_finish().
In ceph_submit_write(), if ceph_inc_osd_stopping_blocker() fails -- which
happens during umount -- the request is aborted before submission: the
already-collected folios are only redirtied and unlocked, so
writepages_finish() never runs and the claim is leaked.
redirty_page_for_writepage() -> folio_redirty_for_writepage() ->
filemap_dirty_folio() sets PG_dirty directly and does not go through
->dirty_folio, so ceph_dirty_folio() is not re-entered to rebalance it.
Because every subsequent writeback also fails the osd_stopping_blocker,
i_wrbuffer_ref never returns to 0, the ihold() is never dropped, and the
inode cannot be evicted:
VFS: Busy inodes after unmount of ceph
kernel BUG at fs/super.c:650!
Release the orphaned claim in the abort path before redirtying, via
ceph_undo_wrbuffer_claim(): detach the snap_context, drop the wrbuffer
reference (letting i_wrbuffer_ref reach 0 and iput() the inode), and drop
the snap_context reference -- i.e. do what writepages_finish() would have
done for these never-submitted folios.
Only the locked_pages entries are undone; folios still in the fbatch were
never dirty-cleared by this call (folio_clear_dirty_for_io() is the
ownership-transfer point, and a successful move NULLs the fbatch slot), so
they hold no claim this call owns. |
| In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: close backchannel before destroying callback service
A backchannel receive can complete a request while the NFS callback
service is being torn down. xprt_complete_bc_request() removes the
request from bc_pa_list, drops bc_alloc_count, marks the request in use,
and then asks xprt_enqueue_bc_request() to hand it to the callback
service.
If teardown has already cleared xprt->bc_serv, xprt_enqueue_bc_request()
currently returns without enqueueing or freeing the committed request.
The xprt_get() taken on entry is leaked as well. If the producer wins
the race before bc_serv is cleared, it can also enqueue onto sv_cb_list
after nfs_callback_down() has stopped the callback threads, leaving the
request linked to a svc_serv that is about to be freed.
Close the producer side before callback threads are stopped. Add
xprt_svc_shutdown_bc() to clear xprt->bc_serv under bc_pa_lock, and call
it on callback shutdown and callback-start failure before stopping the
service threads. Requests that lose the NULL transition in
xprt_enqueue_bc_request() are released through the normal backchannel
free path after balancing bc_slot_count. Finally, drain any remaining
sv_cb_list requests after the callback threads have stopped and before
svc_destroy() frees the service. |
| In the Linux kernel, the following vulnerability has been resolved:
NFS/localio: fix ref leak on nfs_uuid_add_file failure
When nfs_uuid_add_file() races with nfs_uuid_put() tearing down
uuid->net, it returns -ENXIO without publishing nfl->nfs_uuid via
rcu_assign_pointer(). nfs_open_local_fh() then enters its error
branch and only releases the slot's file ref and its paired net
ref plus its own entry-time net ref, while the close path is a
no-op:
nfs_close_local_fh()
nfs_uuid = rcu_dereference(nfl->nfs_uuid);
if (!nfs_uuid) { rcu_read_unlock(); return; } /* always */
nfsd_open_local_fh() returns localio holding a caller-owned +1
nfsd_file reference (from nfsd_file_get() after
nfsd_file_acquire_local()) and an entry-time nfsd_net reference
(from its first nfsd_net_try_get()) embedded as nf->nf_net. Both
are leaked on the failure path, pinning one nfsd_file (and the
underlying struct file, dentry, inode) and one nfsd_net_ref per
occurrence, which blocks nfsd_net and netns teardown.
Fix by releasing the caller-owned file ref and its net ref through
the existing helper, using a stack-local RCU pointer so the helper
can xchg it out, then returning -ENXIO so callers do not
dereference a localio whose slot has been cleared:
struct nfsd_file __rcu *tmp = RCU_INITIALIZER(localio);
nfs_to_nfsd_file_put_local(pnf);
nfs_to_nfsd_file_put_local(&tmp);
localio = ERR_PTR(-ENXIO);
The trailing nfs_to_nfsd_net_put(net) continues to release the
outer net ref, so all three nfsd_net_try_get() increments are
balanced on the error branch. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix dentry ref leak on V4ROOT export filehandle lookup
nfsd_set_fh_dentry() leaks the dentry reference from
exportfs_decode_fh_raw() when the NFS3_FHSIZE or NFS_FHSIZE
switch cases detect NFSEXP_V4ROOT and goto out. The out: label
calls exp_put() but never dput(dentry), and fhp->fh_dentry was
never assigned so fh_put() cannot compensate.
A crafted NFSv3 filehandle targeting a V4ROOT export's fsid
triggers the leak on every request. |
| In the Linux kernel, the following vulnerability has been resolved:
accel/rocket: Fix error path handling in rocket_job_run()
In rocket_job_run(), after taking an extra fence reference for
job->done_fence via dma_fence_get(), the error paths have three bugs:
- The dma_fence reference held by job->done_fence is never released,
causing a reference leak.
- pm_runtime_get_sync() increments the usage counter even on failure,
but the error path does not decrement it, leaking the runtime PM
reference and preventing the NPU from suspending.
- A valid but unsignaled fence is returned to the DRM scheduler,
which triggers WARN("Fence ... released with pending signals!")
when the scheduler drops its reference.
Fix by replacing pm_runtime_get_sync() with pm_runtime_resume_and_get()
which auto-balances the usage counter on failure, releasing both fence
references on error, and returning ERR_PTR(ret) instead of the
unsignaled fence.
[tomeu: Refactored error paths to use consolidated goto labels] |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/amd: Put PCI device after handling PPR faults
iommu_call_iopf_notifier() looks up the requester with
pci_get_domain_bus_and_slot(), which returns a PCI device with its
reference count incremented.
Neither the successful iommu_report_device_fault() path nor the abort
path drops that reference, so every handled PPR request leaks a PCI
device reference.
This is the same ownership rule that was fixed for the old iommu_v2
ppr_notifier() path by commit 6cf0981c2233 ("iommu/amd: Fix pci device
refcount leak in ppr_notifier()"), but iommu_call_iopf_notifier() was
added later as a separate PPR/IOPF notifier path.
Drop the PCI device reference after handling the PPR entry. |
| In the Linux kernel, the following vulnerability has been resolved:
iommufd: Avoid locking internal accesses during unmap
iommufd_access_notify_unmap() skips internal accesses because they do
not have an external unmap callback to invoke.
However, the current test calls iommufd_lock_obj() before checking
whether the access is internal. If iommufd_lock_obj() succeeds, the loop
then sees the internal access and continues, bypassing the matching
iommufd_put_object() used by the normal unmap path. This leaks the
object reference taken by iommufd_lock_obj().
Check for internal accesses first so skipped entries are never locked. |
| In the Linux kernel, the following vulnerability has been resolved:
firmware_loader: fix device reference leak in firmware_upload_register()
firmware_upload_register()
-> fw_create_instance()
-> device_initialize()
After fw_create_instance() succeeds, the lifetime of the embedded struct
device is expected to be managed through the device core reference
counting, since fw_create_instance() has already called
device_initialize().
In firmware_upload_register(), if alloc_lookup_fw_priv() fails after
fw_create_instance() succeeds, the code reaches free_fw_sysfs and frees
fw_sysfs directly instead of releasing the device reference with
put_device(). This may leave the reference count of the embedded struct
device unbalanced, resulting in a refcount leak.
The issue was identified by a static analysis tool I developed and
confirmed by manual review. Fix this by using put_device(fw_dev) in the
failure path and letting fw_dev_release() handle the final cleanup,
instead of freeing the instance directly from the error path. |
| In the Linux kernel, the following vulnerability has been resolved:
netfs: Fix folio->private handling in netfs_perform_write()
Under some circumstances, netfs_perform_write() doesn't correctly
manipulate folio->private between NULL, NETFS_FOLIO_COPY_TO_CACHE, pointing
to a group and pointing to a netfs_folio struct, leading to potential
multiple attachments of private data with associated folio ref leaks and
also leaks of netfs_folio structs or netfs_group refs.
Fix this by consolidating the place at which a folio is marked uptodate in
one place and having that look at what's attached to folio->private and
decide how to clean it up and then set the new group. Also, the content
shouldn't be flushed if group is NULL, even if a group is specified in the
netfs_group parameter, as that would be the case for a new folio. A
filesystem should always specify netfs_group or never specify netfs_group.
The Sashiko auto-review tool noted that it was theoretically possible that
the fpos >= ctx->zero_point section might leak if it modified a streaming
write folio. This is unlikely, but with a network filesystem, third party
changes can happen. It also pointed out that __netfs_set_group() would
leak if called multiple times on the same folio from the "whole folio
modify section". |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix use-after-free in offloaded map/prog info fill
When querying info for an offloaded BPF map or program,
bpf_map_offload_info_fill_ns() and bpf_prog_offload_info_fill_ns()
obtain the network namespace with get_net(dev_net(offmap->netdev)).
However, the associated netdev's netns may be racing with teardown
during netns destruction. If the netns refcount has already reached 0,
get_net() performs a refcount_t increment on 0, triggering:
refcount_t: addition on 0; use-after-free.
Although rtnl_lock and bpf_devs_lock ensure the netdev pointer remains
valid, they cannot prevent the netns refcount from reaching zero.
Fix this by using maybe_get_net() instead of get_net(). maybe_get_net()
uses refcount_inc_not_zero() and returns NULL if the refcount is already
zero, which causes ns_get_path_cb() to fail and the caller to return
-ENOENT -- the correct behavior when the netns is being destroyed. |
| When the JAIL_AT_DESC flag is specified, kern_jail_set() and kern_jail_get() released the reference to the caller's current prison before looking up the jail descriptor. If the descriptor lookup failed, error-handling paths released the same reference a second time.
An unprivileged local user can trigger a prison reference count underflow, which may cause the prison structure to be freed while still in use. When this is done on the jail host, the bug will generally result in an immediate panic. However, if the user is running in a jail, then it may be possible to exploit the bug to elevate privileges. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: disallow multiple FENCE chunks in one submit
amdgpu_cs_pass1() dispatches on chunk_id once per chunk without
rejecting repeated ids. p->uf_bo is a single-slot field, so a
submission carrying two AMDGPU_CHUNK_ID_FENCE chunks runs
amdgpu_cs_p1_user_fence() twice, and the second run overwrites
p->uf_bo with a freshly referenced BO without dropping the reference
taken by the first.
amdgpu_cs_parser_fini() only unrefs the final p->uf_bo, so every FENCE
chunk but the last leaks a BO reference. The leaked BO outlives handle
close and process exit.
Reject duplicate FENCE chunks the same way commit fec5f8e8c6bc
("drm/amdgpu: disallow multiple BO_HANDLES chunks in one submit") did
for p->bo_list.
(cherry picked from commit 665b1fc2a1845206408f9a2c6da67101789edb82) |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_gact, act_police: range check the fallback control action
tcf_action_check_ctrlact() range checks the primary control action:
if (!opcode)
ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0;
TC_ACT_VALUE_MAX is TC_ACT_TRAP, so kernel-internal verdicts above it
cannot be set that way. But act_gact and act_police each carry a second,
independent control action supplied by user space that never reaches that
helper - TCA_GACT_PROB.paction and TCA_POLICE_RESULT. Both only reject
TC_ACT_GOTO_CHAIN, so any other value is stored verbatim and returned
verbatim from the action.
In particular user space can store TC_ACT_CONSUMED, which is
TC_ACT_VALUE_MAX + 1 and is deliberately not part of the UAPI value
range. That verdict tells every caller the action took ownership of the
skb, so nobody frees it: sch_handle_ingress(), sch_handle_egress() and
tcf_qevent_handle() all deliberately skip the free for it. The result is
one leaked sk_buff plus its data buffer per packet traversing the filter,
unbounded, for all traffic on the chain including kernel-generated
packets.
Both are trivially deterministic. act_gact clamps tcfg_pval to >= 1, so
with pval = 1 gact_determ() returns the fallback for every packet.
act_police has no mandatory rate, so rate = 0 leaves tcfp_mtu = ~0 and
tcf_police_mtu_check() always passes.
TC_ACT_CONSUMED was added by commit 720f22fed81b ("net: sched: refactor
reinsert action"), after both goto-chain guards were written:
commit 9469f375ab09 ("net/sched: act_gact: disallow 'goto chain' on
fallback control action") and
commit c08f5ed5d625 ("net/sched: act_police: disallow 'goto chain' on
fallback control action"). Neither guard was widened when the new
verdict appeared.
Factor the existing range test out of tcf_action_check_ctrlact() as
tcf_action_valid() and apply it to both fallbacks. The helper cannot call
tcf_action_check_ctrlact() directly because that also allocates a
goto_chain, which is exactly what these two sites must not do.
Reproduced on v7.2-rc6: kmemleak reports one leaked 232-byte
skbuff_head_cache object plus its 704-byte data buffer per packet. With
this patch both configurations are rejected with -EINVAL and kmemleak
reports none. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: pci: Fix memory accounting for pinned/unpinned pages
The account_mem() and unaccount_mem() functions call get_uid() which
increments the reference count of struct user_struct on every invocation.
But we don't decrement the count by calling free_uid(). It also
accounted/unaccounted the pages against the current->mm. But its possible
the unaccount_mem() can be called from a different process context than the
one that originally pinned the pages.
Let's fix this by storing the pinning process user_struct and mm_struct
when accounting for pinned pages, and subsequently free these resources
when the pages are unpinned.
[borntraeger@linux.ibm.com: Fixed whitespace] |
| In the Linux kernel, the following vulnerability has been resolved:
binfmt_misc: use exe_file_deny_write_access() for the interpreter clone
For MISC_FMT_OPEN_FILE entries load_misc_binary() clones the
registered interpreter file and denies write access to the clone via
plain deny_write_access(). The clone is installed as
bprm->interpreter and later released by the exec machinery through
exe_file_allow_write_access() which skips the i_writecount increment
for files with FMODE_FSNOTIFY_HSM set.
The deny and allow side can therefore come to different conclusions
when pre-content watches are in play: if a pre-content watch is added
to the interpreter after registration every subsequent exec through
that entry takes a write denial on the clone that is never paired
with a write allowance, driving the interpreter inode's i_writecount
further down with each exec and leaving the interpreter unwritable
even after the entry and all its users are gone.
Take the write denial via exe_file_deny_write_access() so both sides
of the pairing base their decision on the same file mode, and
propagate failure instead of silently ignoring it: an interpreter
that is concurrently open for writing now fails the exec with
ETXTBSY, exactly like an interpreter freshly opened via open_exec()
would. |
| In the Linux kernel, the following vulnerability has been resolved:
binfmt_misc: don't leak the user namespace when the mount fails
bm_get_tree() takes a reference to the user namespace and hands it to
get_tree_keyed() as the sget key. sget_fc() moves that reference into
sb->s_fs_info and clears fc->s_fs_info, so from that point on the
superblock owns it and bm_free() doesn't see it anymore.
The superblock drops it in ->put_super(). But generic_shutdown_super()
only calls ->put_super() from inside the if (sb->s_root) branch, so
nothing releases it when bm_fill_super() fails:
- The kzalloc_obj() failure leaves s_root NULL and the whole branch is
skipped.
- A simple_fill_super() failure in the file loop leaves s_root set, but
s_op still points at simple_super_operations, which has no
->put_super(). bm_fill_super() installs s_ops only once
simple_fill_super() returned success, and installing it earlier
wouldn't help either because simple_fill_super() overwrites s_op.
Either way vfs_get_super() calls deactivate_locked_super() and the
reference is gone for good. binfmt_misc mounts are available in a user
namespace and both the inode and the dentry cache are SLAB_ACCOUNT, so
an unprivileged caller under a tight memory cgroup can fail
simple_fill_super() on demand and leak one user namespace per attempt.
Drop the reference in ->kill_sb() instead, which runs unconditionally,
the same way nfsd and rpc_pipefs release their keyed s_fs_info.
That also stops ->put_super() from clearing s_fs_info while the
superblock is still on @fs_supers. generic_shutdown_super() leaves it
there on purpose so that sget_fc() keeps finding it until kill_sb() has
run, but a NULL s_fs_info makes test_keyed_super() miss it, so a
concurrent mount for the same user namespace skips the grab_super()
wait and creates a second superblock for a namespace that is still
being torn down. |
