| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_conntrack: fix crash due to removal of uninitialised entry
A crash in conntrack was reported while trying to unlink the conntrack
entry from the hash bucket list:
[exception RIP: __nf_ct_delete_from_lists+172]
[..]
#7 [ff539b5a2b043aa0] nf_ct_delete at ffffffffc124d421 [nf_conntrack]
#8 [ff539b5a2b043ad0] nf_ct_gc_expired at ffffffffc124d999 [nf_conntrack]
#9 [ff539b5a2b043ae0] __nf_conntrack_find_get at ffffffffc124efbc [nf_conntrack]
[..]
The nf_conn struct is marked as allocated from slab but appears to be in
a partially initialised state:
ct hlist pointer is garbage; looks like the ct hash value
(hence crash).
ct->status is equal to IPS_CONFIRMED|IPS_DYING, which is expected
ct->timeout is 30000 (=30s), which is unexpected.
Everything else looks like normal udp conntrack entry. If we ignore
ct->status and pretend its 0, the entry matches those that are newly
allocated but not yet inserted into the hash:
- ct hlist pointers are overloaded and store/cache the raw tuple hash
- ct->timeout matches the relative time expected for a new udp flow
rather than the absolute 'jiffies' value.
If it were not for the presence of IPS_CONFIRMED,
__nf_conntrack_find_get() would have skipped the entry.
Theory is that we did hit following race:
cpu x cpu y cpu z
found entry E found entry E
E is expired <preemption>
nf_ct_delete()
return E to rcu slab
init_conntrack
E is re-inited,
ct->status set to 0
reply tuplehash hnnode.pprev
stores hash value.
cpu y found E right before it was deleted on cpu x.
E is now re-inited on cpu z. cpu y was preempted before
checking for expiry and/or confirm bit.
->refcnt set to 1
E now owned by skb
->timeout set to 30000
If cpu y were to resume now, it would observe E as
expired but would skip E due to missing CONFIRMED bit.
nf_conntrack_confirm gets called
sets: ct->status |= CONFIRMED
This is wrong: E is not yet added
to hashtable.
cpu y resumes, it observes E as expired but CONFIRMED:
<resumes>
nf_ct_expired()
-> yes (ct->timeout is 30s)
confirmed bit set.
cpu y will try to delete E from the hashtable:
nf_ct_delete() -> set DYING bit
__nf_ct_delete_from_lists
Even this scenario doesn't guarantee a crash:
cpu z still holds the table bucket lock(s) so y blocks:
wait for spinlock held by z
CONFIRMED is set but there is no
guarantee ct will be added to hash:
"chaintoolong" or "clash resolution"
logic both skip the insert step.
reply hnnode.pprev still stores the
hash value.
unlocks spinlock
return NF_DROP
<unblocks, then
crashes on hlist_nulls_del_rcu pprev>
In case CPU z does insert the entry into the hashtable, cpu y will unlink
E again right away but no crash occurs.
Without 'cpu y' race, 'garbage' hlist is of no consequence:
ct refcnt remains at 1, eventually skb will be free'd and E gets
destroyed via: nf_conntrack_put -> nf_conntrack_destroy -> nf_ct_destroy.
To resolve this, move the IPS_CONFIRMED assignment after the table
insertion but before the unlock.
Pablo points out that the confirm-bit-store could be reordered to happen
before hlist add resp. the timeout fixup, so switch to set_bit and
before_atomic memory barrier to prevent this.
It doesn't matter if other CPUs can observe a newly inserted entry right
before the CONFIRMED bit was set:
Such event cannot be distinguished from above "E is the old incarnation"
case: the entry will be skipped.
Also change nf_ct_should_gc() to first check the confirmed bit.
The gc sequence is:
1. Check if entry has expired, if not skip to next entry
2. Obtain a reference to the expired entry.
3. Call nf_ct_should_gc() to double-check step 1.
nf_ct_should_gc() is thus called only for entries that already failed an
expiry check. After this patch, once the confirmed bit check pas
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
bus: mhi: ep: Update read pointer only after buffer is written
Inside mhi_ep_ring_add_element, the read pointer (rd_offset) is updated
before the buffer is written, potentially causing race conditions where
the host sees an updated read pointer before the buffer is actually
written. Updating rd_offset prematurely can lead to the host accessing
an uninitialized or incomplete element, resulting in data corruption.
Invoke the buffer write before updating rd_offset to ensure the element
is fully written before signaling its availability. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix iteration of extrefs during log replay
At __inode_add_ref() when processing extrefs, if we jump into the next
label we have an undefined value of victim_name.len, since we haven't
initialized it before we did the goto. This results in an invalid memory
access in the next iteration of the loop since victim_name.len was not
initialized to the length of the name of the current extref.
Fix this by initializing victim_name.len with the current extref's name
length. |
| In the Linux kernel, the following vulnerability has been resolved:
sunrpc: handle SVC_GARBAGE during svc auth processing as auth error
tianshuo han reported a remotely-triggerable crash if the client sends a
kernel RPC server a specially crafted packet. If decoding the RPC reply
fails in such a way that SVC_GARBAGE is returned without setting the
rq_accept_statp pointer, then that pointer can be dereferenced and a
value stored there.
If it's the first time the thread has processed an RPC, then that
pointer will be set to NULL and the kernel will crash. In other cases,
it could create a memory scribble.
The server sunrpc code treats a SVC_GARBAGE return from svc_authenticate
or pg_authenticate as if it should send a GARBAGE_ARGS reply. RFC 5531
says that if authentication fails that the RPC should be rejected
instead with a status of AUTH_ERR.
Handle a SVC_GARBAGE return as an AUTH_ERROR, with a reason of
AUTH_BADCRED instead of returning GARBAGE_ARGS in that case. This
sidesteps the whole problem of touching the rpc_accept_statp pointer in
this situation and avoids the crash. |
| In the Linux kernel, the following vulnerability has been resolved:
sched_ext: bpf_iter_scx_dsq_new() should always initialize iterator
BPF programs may call next() and destroy() on BPF iterators even after new()
returns an error value (e.g. bpf_for_each() macro ignores error returns from
new()). bpf_iter_scx_dsq_new() could leave the iterator in an uninitialized
state after an error return causing bpf_iter_scx_dsq_next() to dereference
garbage data. Make bpf_iter_scx_dsq_new() always clear $kit->dsq so that
next() and destroy() become noops. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Fix uninitialized memcache pointer in user_mem_abort()
Commit fce886a60207 ("KVM: arm64: Plumb the pKVM MMU in KVM") made the
initialization of the local memcache variable in user_mem_abort()
conditional, leaving a codepath where it is used uninitialized via
kvm_pgtable_stage2_map().
This can fail on any path that requires a stage-2 allocation
without transition via a permission fault or dirty logging.
Fix this by making sure that memcache is always valid. |
| In the Linux kernel, the following vulnerability has been resolved:
pds_core: handle unsupported PDS_CORE_CMD_FW_CONTROL result
If the FW doesn't support the PDS_CORE_CMD_FW_CONTROL command
the driver might at the least print garbage and at the worst
crash when the user runs the "devlink dev info" devlink command.
This happens because the stack variable fw_list is not 0
initialized which results in fw_list.num_fw_slots being a
garbage value from the stack. Then the driver tries to access
fw_list.fw_names[i] with i >= ARRAY_SIZE and runs off the end
of the array.
Fix this by initializing the fw_list and by not failing
completely if the devcmd fails because other useful information
is printed via devlink dev info even if the devcmd fails. |
| In the Linux kernel, the following vulnerability has been resolved:
ethtool: cmis_cdb: use correct rpl size in ethtool_cmis_module_poll()
rpl is passed as a pointer to ethtool_cmis_module_poll(), so the correct
size of rpl is sizeof(*rpl) which should be just 1 byte. Using the
pointer size instead can cause stack corruption:
Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ethtool_cmis_wait_for_cond+0xf4/0x100
CPU: 72 UID: 0 PID: 4440 Comm: kworker/72:2 Kdump: loaded Tainted: G OE 6.11.0 #24
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Dell Inc. PowerEdge R760/04GWWM, BIOS 1.6.6 09/20/2023
Workqueue: events module_flash_fw_work
Call Trace:
<TASK>
panic+0x339/0x360
? ethtool_cmis_wait_for_cond+0xf4/0x100
? __pfx_status_success+0x10/0x10
? __pfx_status_fail+0x10/0x10
__stack_chk_fail+0x10/0x10
ethtool_cmis_wait_for_cond+0xf4/0x100
ethtool_cmis_cdb_execute_cmd+0x1fc/0x330
? __pfx_status_fail+0x10/0x10
cmis_cdb_module_features_get+0x6d/0xd0
ethtool_cmis_cdb_init+0x8a/0xd0
ethtool_cmis_fw_update+0x46/0x1d0
module_flash_fw_work+0x17/0xa0
process_one_work+0x179/0x390
worker_thread+0x239/0x340
? __pfx_worker_thread+0x10/0x10
kthread+0xcc/0x100
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2d/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nfnetlink_queue: Initialize ctx to avoid memory allocation error
It is possible that ctx in nfqnl_build_packet_message() could be used
before it is properly initialize, which is only initialized
by nfqnl_get_sk_secctx().
This patch corrects this problem by initializing the lsmctx to a safe
value when it is declared.
This is similar to the commit 35fcac7a7c25
("audit: Initialize lsmctx to avoid memory allocation error"). |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Unconditionally save+flush host FPSIMD/SVE/SME state
There are several problems with the way hyp code lazily saves the host's
FPSIMD/SVE state, including:
* Host SVE being discarded unexpectedly due to inconsistent
configuration of TIF_SVE and CPACR_ELx.ZEN. This has been seen to
result in QEMU crashes where SVE is used by memmove(), as reported by
Eric Auger:
https://issues.redhat.com/browse/RHEL-68997
* Host SVE state is discarded *after* modification by ptrace, which was an
unintentional ptrace ABI change introduced with lazy discarding of SVE state.
* The host FPMR value can be discarded when running a non-protected VM,
where FPMR support is not exposed to a VM, and that VM uses
FPSIMD/SVE. In these cases the hyp code does not save the host's FPMR
before unbinding the host's FPSIMD/SVE/SME state, leaving a stale
value in memory.
Avoid these by eagerly saving and "flushing" the host's FPSIMD/SVE/SME
state when loading a vCPU such that KVM does not need to save any of the
host's FPSIMD/SVE/SME state. For clarity, fpsimd_kvm_prepare() is
removed and the necessary call to fpsimd_save_and_flush_cpu_state() is
placed in kvm_arch_vcpu_load_fp(). As 'fpsimd_state' and 'fpmr_ptr'
should not be used, they are set to NULL; all uses of these will be
removed in subsequent patches.
Historical problems go back at least as far as v5.17, e.g. erroneous
assumptions about TIF_SVE being clear in commit:
8383741ab2e773a9 ("KVM: arm64: Get rid of host SVE tracking/saving")
... and so this eager save+flush probably needs to be backported to ALL
stable trees. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix incorrect validation for num_aces field of smb_acl
parse_dcal() validate num_aces to allocate posix_ace_state_array.
if (num_aces > ULONG_MAX / sizeof(struct smb_ace *))
It is an incorrect validation that we can create an array of size ULONG_MAX.
smb_acl has ->size field to calculate actual number of aces in request buffer
size. Use this to check invalid num_aces. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/netfs/read_collect: add to next->prev_donated
If multiple subrequests donate data to the same "next" request
(depending on the subrequest completion order), each of them would
overwrite the `prev_donated` field, causing data corruption and a
BUG() crash ("Can't donate prior to front"). |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_conncount: Fully initialize struct nf_conncount_tuple in insert_tree()
Since commit b36e4523d4d5 ("netfilter: nf_conncount: fix garbage
collection confirm race"), `cpu` and `jiffies32` were introduced to
the struct nf_conncount_tuple.
The commit made nf_conncount_add() initialize `conn->cpu` and
`conn->jiffies32` when allocating the struct.
In contrast, count_tree() was not changed to initialize them.
By commit 34848d5c896e ("netfilter: nf_conncount: Split insert and
traversal"), count_tree() was split and the relevant allocation
code now resides in insert_tree().
Initialize `conn->cpu` and `conn->jiffies32` in insert_tree().
BUG: KMSAN: uninit-value in find_or_evict net/netfilter/nf_conncount.c:117 [inline]
BUG: KMSAN: uninit-value in __nf_conncount_add+0xd9c/0x2850 net/netfilter/nf_conncount.c:143
find_or_evict net/netfilter/nf_conncount.c:117 [inline]
__nf_conncount_add+0xd9c/0x2850 net/netfilter/nf_conncount.c:143
count_tree net/netfilter/nf_conncount.c:438 [inline]
nf_conncount_count+0x82f/0x1e80 net/netfilter/nf_conncount.c:521
connlimit_mt+0x7f6/0xbd0 net/netfilter/xt_connlimit.c:72
__nft_match_eval net/netfilter/nft_compat.c:403 [inline]
nft_match_eval+0x1a5/0x300 net/netfilter/nft_compat.c:433
expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
nft_do_chain+0x426/0x2290 net/netfilter/nf_tables_core.c:288
nft_do_chain_ipv4+0x1a5/0x230 net/netfilter/nft_chain_filter.c:23
nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626
nf_hook_slow_list+0x24d/0x860 net/netfilter/core.c:663
NF_HOOK_LIST include/linux/netfilter.h:350 [inline]
ip_sublist_rcv+0x17b7/0x17f0 net/ipv4/ip_input.c:633
ip_list_rcv+0x9ef/0xa40 net/ipv4/ip_input.c:669
__netif_receive_skb_list_ptype net/core/dev.c:5936 [inline]
__netif_receive_skb_list_core+0x15c5/0x1670 net/core/dev.c:5983
__netif_receive_skb_list net/core/dev.c:6035 [inline]
netif_receive_skb_list_internal+0x1085/0x1700 net/core/dev.c:6126
netif_receive_skb_list+0x5a/0x460 net/core/dev.c:6178
xdp_recv_frames net/bpf/test_run.c:280 [inline]
xdp_test_run_batch net/bpf/test_run.c:361 [inline]
bpf_test_run_xdp_live+0x2e86/0x3480 net/bpf/test_run.c:390
bpf_prog_test_run_xdp+0xf1d/0x1ae0 net/bpf/test_run.c:1316
bpf_prog_test_run+0x5e5/0xa30 kernel/bpf/syscall.c:4407
__sys_bpf+0x6aa/0xd90 kernel/bpf/syscall.c:5813
__do_sys_bpf kernel/bpf/syscall.c:5902 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5900 [inline]
__ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5900
ia32_sys_call+0x394d/0x4180 arch/x86/include/generated/asm/syscalls_32.h:358
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:387
do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:412
do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:450
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
Uninit was created at:
slab_post_alloc_hook mm/slub.c:4121 [inline]
slab_alloc_node mm/slub.c:4164 [inline]
kmem_cache_alloc_noprof+0x915/0xe10 mm/slub.c:4171
insert_tree net/netfilter/nf_conncount.c:372 [inline]
count_tree net/netfilter/nf_conncount.c:450 [inline]
nf_conncount_count+0x1415/0x1e80 net/netfilter/nf_conncount.c:521
connlimit_mt+0x7f6/0xbd0 net/netfilter/xt_connlimit.c:72
__nft_match_eval net/netfilter/nft_compat.c:403 [inline]
nft_match_eval+0x1a5/0x300 net/netfilter/nft_compat.c:433
expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
nft_do_chain+0x426/0x2290 net/netfilter/nf_tables_core.c:288
nft_do_chain_ipv4+0x1a5/0x230 net/netfilter/nft_chain_filter.c:23
nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626
nf_hook_slow_list+0x24d/0x860 net/netfilter/core.c:663
NF_HOOK_LIST include/linux/netfilter.h:350 [inline]
ip_sublist_rcv+0x17b7/0x17f0 net/ipv4/ip_input.c:633
ip_list_rcv+0x9ef/0xa40 net/ip
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
amdkfd: properly free gang_ctx_bo when failed to init user queue
The destructor of a gtt bo is declared as
void amdgpu_amdkfd_free_gtt_mem(struct amdgpu_device *adev, void **mem_obj);
Which takes void** as the second parameter.
GCC allows passing void* to the function because void* can be implicitly
casted to any other types, so it can pass compiling.
However, passing this void* parameter into the function's
execution process(which expects void** and dereferencing void**)
will result in errors. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Fix the warning "__rxe_cleanup+0x12c/0x170 [rdma_rxe]"
The Call Trace is as below:
"
<TASK>
? show_regs.cold+0x1a/0x1f
? __rxe_cleanup+0x12c/0x170 [rdma_rxe]
? __warn+0x84/0xd0
? __rxe_cleanup+0x12c/0x170 [rdma_rxe]
? report_bug+0x105/0x180
? handle_bug+0x46/0x80
? exc_invalid_op+0x19/0x70
? asm_exc_invalid_op+0x1b/0x20
? __rxe_cleanup+0x12c/0x170 [rdma_rxe]
? __rxe_cleanup+0x124/0x170 [rdma_rxe]
rxe_destroy_qp.cold+0x24/0x29 [rdma_rxe]
ib_destroy_qp_user+0x118/0x190 [ib_core]
rdma_destroy_qp.cold+0x43/0x5e [rdma_cm]
rtrs_cq_qp_destroy.cold+0x1d/0x2b [rtrs_core]
rtrs_srv_close_work.cold+0x1b/0x31 [rtrs_server]
process_one_work+0x21d/0x3f0
worker_thread+0x4a/0x3c0
? process_one_work+0x3f0/0x3f0
kthread+0xf0/0x120
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x22/0x30
</TASK>
"
When too many rdma resources are allocated, rxe needs more time to
handle these rdma resources. Sometimes with the current timeout, rxe
can not release the rdma resources correctly.
Compared with other rdma drivers, a bigger timeout is used. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Cancel the running bpf_timer through kworker for PREEMPT_RT
During the update procedure, when overwrite element in a pre-allocated
htab, the freeing of old_element is protected by the bucket lock. The
reason why the bucket lock is necessary is that the old_element has
already been stashed in htab->extra_elems after alloc_htab_elem()
returns. If freeing the old_element after the bucket lock is unlocked,
the stashed element may be reused by concurrent update procedure and the
freeing of old_element will run concurrently with the reuse of the
old_element. However, the invocation of check_and_free_fields() may
acquire a spin-lock which violates the lockdep rule because its caller
has already held a raw-spin-lock (bucket lock). The following warning
will be reported when such race happens:
BUG: scheduling while atomic: test_progs/676/0x00000003
3 locks held by test_progs/676:
#0: ffffffff864b0240 (rcu_read_lock_trace){....}-{0:0}, at: bpf_prog_test_run_syscall+0x2c0/0x830
#1: ffff88810e961188 (&htab->lockdep_key){....}-{2:2}, at: htab_map_update_elem+0x306/0x1500
#2: ffff8881f4eac1b8 (&base->softirq_expiry_lock){....}-{2:2}, at: hrtimer_cancel_wait_running+0xe9/0x1b0
Modules linked in: bpf_testmod(O)
Preemption disabled at:
[<ffffffff817837a3>] htab_map_update_elem+0x293/0x1500
CPU: 0 UID: 0 PID: 676 Comm: test_progs Tainted: G ... 6.12.0+ #11
Tainted: [W]=WARN, [O]=OOT_MODULE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)...
Call Trace:
<TASK>
dump_stack_lvl+0x57/0x70
dump_stack+0x10/0x20
__schedule_bug+0x120/0x170
__schedule+0x300c/0x4800
schedule_rtlock+0x37/0x60
rtlock_slowlock_locked+0x6d9/0x54c0
rt_spin_lock+0x168/0x230
hrtimer_cancel_wait_running+0xe9/0x1b0
hrtimer_cancel+0x24/0x30
bpf_timer_delete_work+0x1d/0x40
bpf_timer_cancel_and_free+0x5e/0x80
bpf_obj_free_fields+0x262/0x4a0
check_and_free_fields+0x1d0/0x280
htab_map_update_elem+0x7fc/0x1500
bpf_prog_9f90bc20768e0cb9_overwrite_cb+0x3f/0x43
bpf_prog_ea601c4649694dbd_overwrite_timer+0x5d/0x7e
bpf_prog_test_run_syscall+0x322/0x830
__sys_bpf+0x135d/0x3ca0
__x64_sys_bpf+0x75/0xb0
x64_sys_call+0x1b5/0xa10
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
...
</TASK>
It seems feasible to break the reuse and refill of per-cpu extra_elems
into two independent parts: reuse the per-cpu extra_elems with bucket
lock being held and refill the old_element as per-cpu extra_elems after
the bucket lock is unlocked. However, it will make the concurrent
overwrite procedures on the same CPU return unexpected -E2BIG error when
the map is full.
Therefore, the patch fixes the lock problem by breaking the cancelling
of bpf_timer into two steps for PREEMPT_RT:
1) use hrtimer_try_to_cancel() and check its return value
2) if the timer is running, use hrtimer_cancel() through a kworker to
cancel it again
Considering that the current implementation of hrtimer_cancel() will try
to acquire a being held softirq_expiry_lock when the current timer is
running, these steps above are reasonable. However, it also has
downside. When the timer is running, the cancelling of the timer is
delayed when releasing the last map uref. The delay is also fixable
(e.g., break the cancelling of bpf timer into two parts: one part in
locked scope, another one in unlocked scope), it can be revised later if
necessary.
It is a bit hard to decide the right fix tag. One reason is that the
problem depends on PREEMPT_RT which is enabled in v6.12. Considering the
softirq_expiry_lock lock exists since v5.4 and bpf_timer is introduced
in v5.15, the bpf_timer commit is used in the fixes tag and an extra
depends-on tag is added to state the dependency on PREEMPT_RT.
Depends-on: v6.12+ with PREEMPT_RT enabled |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: fix hang in nfsd4_shutdown_callback
If nfs4_client is in courtesy state then there is no point to send
the callback. This causes nfsd4_shutdown_callback to hang since
cl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP
notifies NFSD that the connection was dropped.
This patch modifies nfsd4_run_cb_work to skip the RPC call if
nfs4_client is in courtesy state. |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: consolidate suboption status
MPTCP maintains the received sub-options status is the bitmask carrying
the received suboptions and in several bitfields carrying per suboption
additional info.
Zeroing the bitmask before parsing is not enough to ensure a consistent
status, and the MPTCP code has to additionally clear some bitfiled
depending on the actually parsed suboption.
The above schema is fragile, and syzbot managed to trigger a path where
a relevant bitfield is not cleared/initialized:
BUG: KMSAN: uninit-value in __mptcp_expand_seq net/mptcp/options.c:1030 [inline]
BUG: KMSAN: uninit-value in mptcp_expand_seq net/mptcp/protocol.h:864 [inline]
BUG: KMSAN: uninit-value in ack_update_msk net/mptcp/options.c:1060 [inline]
BUG: KMSAN: uninit-value in mptcp_incoming_options+0x2036/0x3d30 net/mptcp/options.c:1209
__mptcp_expand_seq net/mptcp/options.c:1030 [inline]
mptcp_expand_seq net/mptcp/protocol.h:864 [inline]
ack_update_msk net/mptcp/options.c:1060 [inline]
mptcp_incoming_options+0x2036/0x3d30 net/mptcp/options.c:1209
tcp_data_queue+0xb4/0x7be0 net/ipv4/tcp_input.c:5233
tcp_rcv_established+0x1061/0x2510 net/ipv4/tcp_input.c:6264
tcp_v4_do_rcv+0x7f3/0x11a0 net/ipv4/tcp_ipv4.c:1916
tcp_v4_rcv+0x51df/0x5750 net/ipv4/tcp_ipv4.c:2351
ip_protocol_deliver_rcu+0x2a3/0x13d0 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x336/0x500 net/ipv4/ip_input.c:233
NF_HOOK include/linux/netfilter.h:314 [inline]
ip_local_deliver+0x21f/0x490 net/ipv4/ip_input.c:254
dst_input include/net/dst.h:460 [inline]
ip_rcv_finish+0x4a2/0x520 net/ipv4/ip_input.c:447
NF_HOOK include/linux/netfilter.h:314 [inline]
ip_rcv+0xcd/0x380 net/ipv4/ip_input.c:567
__netif_receive_skb_one_core net/core/dev.c:5704 [inline]
__netif_receive_skb+0x319/0xa00 net/core/dev.c:5817
process_backlog+0x4ad/0xa50 net/core/dev.c:6149
__napi_poll+0xe7/0x980 net/core/dev.c:6902
napi_poll net/core/dev.c:6971 [inline]
net_rx_action+0xa5a/0x19b0 net/core/dev.c:7093
handle_softirqs+0x1a0/0x7c0 kernel/softirq.c:561
__do_softirq+0x14/0x1a kernel/softirq.c:595
do_softirq+0x9a/0x100 kernel/softirq.c:462
__local_bh_enable_ip+0x9f/0xb0 kernel/softirq.c:389
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline]
__dev_queue_xmit+0x2758/0x57d0 net/core/dev.c:4493
dev_queue_xmit include/linux/netdevice.h:3168 [inline]
neigh_hh_output include/net/neighbour.h:523 [inline]
neigh_output include/net/neighbour.h:537 [inline]
ip_finish_output2+0x187c/0x1b70 net/ipv4/ip_output.c:236
__ip_finish_output+0x287/0x810
ip_finish_output+0x4b/0x600 net/ipv4/ip_output.c:324
NF_HOOK_COND include/linux/netfilter.h:303 [inline]
ip_output+0x15f/0x3f0 net/ipv4/ip_output.c:434
dst_output include/net/dst.h:450 [inline]
ip_local_out net/ipv4/ip_output.c:130 [inline]
__ip_queue_xmit+0x1f2a/0x20d0 net/ipv4/ip_output.c:536
ip_queue_xmit+0x60/0x80 net/ipv4/ip_output.c:550
__tcp_transmit_skb+0x3cea/0x4900 net/ipv4/tcp_output.c:1468
tcp_transmit_skb net/ipv4/tcp_output.c:1486 [inline]
tcp_write_xmit+0x3b90/0x9070 net/ipv4/tcp_output.c:2829
__tcp_push_pending_frames+0xc4/0x380 net/ipv4/tcp_output.c:3012
tcp_send_fin+0x9f6/0xf50 net/ipv4/tcp_output.c:3618
__tcp_close+0x140c/0x1550 net/ipv4/tcp.c:3130
__mptcp_close_ssk+0x74e/0x16f0 net/mptcp/protocol.c:2496
mptcp_close_ssk+0x26b/0x2c0 net/mptcp/protocol.c:2550
mptcp_pm_nl_rm_addr_or_subflow+0x635/0xd10 net/mptcp/pm_netlink.c:889
mptcp_pm_nl_rm_subflow_received net/mptcp/pm_netlink.c:924 [inline]
mptcp_pm_flush_addrs_and_subflows net/mptcp/pm_netlink.c:1688 [inline]
mptcp_nl_flush_addrs_list net/mptcp/pm_netlink.c:1709 [inline]
mptcp_pm_nl_flush_addrs_doit+0xe10/0x1630 net/mptcp/pm_netlink.c:1750
genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline]
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_fs: Initialize epfile->in early to fix endpoint direction checks
When parsing endpoint descriptors, ffs_data_got_descs() generates the
eps_addrmap which contains the endpoint direction. However, epfile->in
was previously only populated in ffs_func_eps_enable() which executes
upon USB host connection. As a result, early userspace ioctls like
FUNCTIONFS_DMABUF_ATTACH that run before the host connects would see
epfile->in as 0, leading to incorrect DMA directions.
By moving the initialization to ffs_epfiles_create(), epfile->in is
accurate before userspace opens the endpoint files. |
| In the Linux kernel, the following vulnerability has been resolved:
rust_binder: use a u64 stride when cleaning up the offsets array
Allocation's Drop walks the offsets array (binder_size_t = u64 entries),
cleaning up the objects, but it used usize instead of u64 for both the
stride and the per-entry read.
On 64-bit kernels (usize == u64) this is harmless, but on 32-bit kernels
it walks the 8-byte entries in 4-byte steps, iterating an N-entry array
2N times, and reads the always-zero high word as offset 0, cleaning up
the object at offset 0 N extra times. As a result the referenced node or
handle ends up with a lower reference count than it actually has (a
refcount over-decrement), and binder's reference accounting is corrupted;
for example, the owner can be notified of a strong reference release
(BR_RELEASE) even though references still remain.
Change the stride to u64, and read each entry as a u64, narrowing it to
usize with try_into().
On 32-bit ARM, when this over-decrement would drive a count below zero,
the driver's existing refcount guard refuses it and fires:
rust_binder: Failure: refcount underflow! |
