| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
posix-cpu-timers: Prevent UAF caused by non-leader exec() race
Wongi and Jungwoo decoded and reported a non-leader exec() related race
which can result in an UAF:
sys_timer_delete() exec()
posix_cpu_timer_del()
// Observes old leader
p = pid_task(pid, pid_type); de_thread()
switch_leader();
release_task(old_leader)
__exit_signal(old_leader)
sighand = lock(old_leader, sighand);
posix_cpu_timers*_exit();
sighand = lock_task_sighand(p) unhash_task(old_leader);
sh = lock(p, sighand) old_leader->sighand = NULL;
unlock(sighand);
(p->sighand == NULL)
unlock(sh)
return NULL;
// Returns without action
if(!sighand)
return 0;
free_posix_timer();
This is "harmless" unless the deleted timer was armed and enqueued in
p->signal because on exec() a TGID targeted timer is inherited.
As sys_timer_delete() freed the underlying posix timer object
run_posix_cpu_timers() or any timerqueue related add/delete operations on
other timers will access the freed object's timerqueue node, which results
in an UAF.
There is a similar problem vs. posix_cpu_timer_set(). For regular posix
timers it just transiently returns -ESRCH to user space, but for the use
case in do_cpu_nanosleep() it's the same UAF just that the k_itimer is
allocated on the stack.
Also posix_cpu_timer_rearm() fails to rearm the timer, which means it stops
to expire.
While debating solutions Frederic pointed out another problem:
posix_cpu_timer_del(tmr)
__exit_signal(p)
posix_cpu_timers*_exit(p);
unhash_task(p);
p->sighand = NULL;
sh = lock_task_sighand(p)
sighand = p->sighand;
if (!sighand)
return NULL;
lock(sighand);
if (!sh)
WARN_ON_ONCE(timer_queued(tmr));
On weakly ordered architectures it is not guaranteed that
posix_cpu_timer_del() will observe the stores in posix_cpu_timers*_exit()
when p->sighand is observed as NULL, which means the WARN() can be a false
positive.
Solve these issues by:
1) Changing the store in __exit_signal() to smp_store_release().
2) Adding a smp_acquire__after_ctrl_dep() into the !sighand path
of lock_task_sighand().
3) Creating a helper function for looking up the task and locking sighand
which does not return when sighand == NULL. Instead it retries the
task lookup and only if that fails it gives up.
4) Using that helper in the three affected functions.
#1/#2 ensures that the reader side which observes sighand == NULL also
observes all preceeding stores, i.e. the stores in posix_cpu_timers*_exit()
and the ones in unhash_task().
#3 ensures that the above described non-leader exec() situation is handled
gracefully. When the task lookup returns the old leader, but sighand ==
NULL then it retries. In the non-leader exec() case the subsequent task
lookup will observe the new leader due to #1/#2. In normal exit() scenarios
the subsequent lookup fails.
When the task lookup fails, the function also checks whether the timer is
still enqueued and issues a warning if that's the case. Unfortunately there
is nothing which can be done about it, but as the task is already not
longer visible the timer should not be accessed anymore. This check also
requires memory ordering, which is not provided when the first lookup
fails. To achieve that the check is preceeded by a smp_rmb() which pairs
with the smp_wmb() in write_seqlock() in __exit_signal(). That ensures that
the stores in posix_cpu_timers*_exit() are visible.
The history of the non-leader exec() issue goes back to the early days of
posix CPU timers, which stored a pointer to the group leader task in the
timer. That obviously fails when a non-leader exec() switches the leader.
commit e0a70217107e ("posix-cpu-timers: workaround to suppress the problems
with mt exec") added a temporary workaround for that in 2010 which surv
---truncated--- |
| A local privilege escalation vulnerability in the init-script for user-applications allows a low-privileged local user to execute arbitrary commands as root, resulting in full system compromise. |
| An out-of-bounds read vulnerability was found in the VA JPEG decoder in GStreamer's gst-plugins-bad. The JPEG parser reads a segment length value from the bitstream without validating it against available data. A remote attacker could trick a user into opening a specially crafted JPEG file, causing downstream parsing to read beyond the provided input buffer, leading to a crash or potential information disclosure. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/pkey: Check length in PKEY_VERIFYPROTK ioctl
Explicitly check the buffer length request structure provided by
user-space and fail, if it exceeds the buffer size. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/pkey: Check length in pkey_pckmo handler implementation
Explicitly check the length of the target buffer in the pkey_pckmo
implementation of the key_to_protkey() handler function. The handler
function fails, if the generated output data exceeds the length of the
provided target buffer. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb()
l2cap_sock_new_connection_cb() returned l2cap_pi(sk)->chan after
release_sock(parent). Once the parent lock is dropped the newly
enqueued child socket sk is reachable via the accept queue, so another
task can accept and free it before the callback dereferences sk,
resulting in a use-after-free.
Rework the ->new_connection() op so the core, rather than the callback,
owns the child channel's lifetime. The op now receives a pre-allocated
new_chan and returns an errno instead of allocating and returning a
channel. l2cap_new_connection() allocates the child channel and links
it into the conn list via __l2cap_chan_add() before invoking the
callback, so the conn-list reference keeps the channel alive once
release_sock(parent) exposes the socket to other tasks.
Channel configuration that was duplicated in l2cap_sock_init() and the
various new_connection callbacks is consolidated into
l2cap_chan_set_defaults(), which now inherits from the parent channel
when one is supplied. |
| In the Linux kernel, the following vulnerability has been resolved:
perf/core: Detach event groups during remove_on_exec
perf_event_remove_on_exec() removes events by calling
perf_event_exit_event(). For top-level events, this removes the event from
the context with DETACH_EXIT only.
This can leave inconsistent group state when a removed event is a group
leader and the group contains siblings without remove_on_exec. If the group
was active, the surviving siblings can remain active and attached to the
removed leader's sibling list, but are no longer represented by a valid
group leader on the PMU context active lists.
A later close of the removed leader uses DETACH_GROUP and can promote the
still-active siblings from this stale group state. The next schedule-in can
then add an already-linked active_list entry again, corrupting the PMU
context active list.
With DEBUG_LIST enabled, this is caught as a list_add double-add in
merge_sched_in().
Fix this by detaching group relationships when remove_on_exec removes an
event. This preserves the existing task-exit and revoke behavior, while
ensuring surviving siblings are ungrouped before the removed event leaves
the context. |
| In the Linux kernel, the following vulnerability has been resolved:
virtio-net: fix len check in receive_big()
receive_big() bounds the device-announced length by
(big_packets_num_skbfrags + 1) * PAGE_SIZE. That is still too loose:
add_recvbuf_big() sets sg[1] to start at offset
sizeof(struct padded_vnet_hdr) into the first page, so the chain
actually carries hdr_len + (PAGE_SIZE - sizeof(padded_vnet_hdr)) +
big_packets_num_skbfrags * PAGE_SIZE bytes -- 20 bytes less than the
check allows for the common hdr_len == 12 case.
A malicious virtio backend can announce a len in that gap. page_to_skb()
then walks one frag past the page chain, storing a NULL page->private
into skb_shinfo()->frags[MAX_SKB_FRAGS], which is both an out-of-bounds
write past the static frag array and a NULL frag handed up the rx path.
Bound len by the size add_recvbuf_big() actually advertised. |
| In the Linux kernel, the following vulnerability has been resolved:
net: qualcomm: rmnet: validate MAP frame length before ingress parsing
When ingress deaggregation is disabled, rmnet_map_ingress_handler() passes
the skb straight to __rmnet_map_ingress_handler(), skipping the length
validation that rmnet_map_deaggregate() performs on the aggregated path.
The parser then dereferences the MAP header and csum header/trailer based on
the on-wire pkt_len without checking skb->len, so a short frame is read out
of bounds:
BUG: KASAN: slab-out-of-bounds in rmnet_map_checksum_downlink_packet
Read of size 1 at addr ffff88801118ed00 by task exploit/147
Call Trace:
...
rmnet_map_checksum_downlink_packet (drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c:413)
__rmnet_map_ingress_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:96)
rmnet_rx_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:129)
__netif_receive_skb_core.constprop.0 (net/core/dev.c:6089)
netif_receive_skb (net/core/dev.c:6460)
tun_get_user (drivers/net/tun.c:1955)
tun_chr_write_iter (drivers/net/tun.c:2001)
vfs_write (fs/read_write.c:688)
ksys_write (fs/read_write.c:740)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
...
Factor that validation out of rmnet_map_deaggregate() into
rmnet_map_validate_packet_len() and run it on the no-aggregation path too.
The MAP header is bounds-checked first, since this path can receive a frame
shorter than the header. |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: net1080: validate packet_len before pad-byte access in rx_fixup
For an even packet_len, net1080_rx_fixup() reads the pad byte at
skb->data[packet_len] before the skb->len != packet_len check further
down, and packet_len is only bounded against NC_MAX_PACKET. A malicious
NetChip 1080 device can send a short frame advertising a large even
packet_len (e.g. 0x4000), so the pad-byte read lands past the end of the
skb:
BUG: KASAN: slab-out-of-bounds in net1080_rx_fixup
Read of size 1 at addr ffff8880106c83c6 by task ksoftirqd/0/14
...
net1080_rx_fixup (drivers/net/usb/net1080.c:384)
usbnet_bh (drivers/net/usb/usbnet.c:1589)
process_one_work (kernel/workqueue.c:3322)
bh_worker (kernel/workqueue.c:3708)
tasklet_action (kernel/softirq.c:965)
handle_softirqs (kernel/softirq.c:622)
...
Reject the frame when packet_len >= skb->len before reading. |
| In the Linux kernel, the following vulnerability has been resolved:
net, bpf: check master for NULL in xdp_master_redirect()
xdp_master_redirect() dereferences the result of
netdev_master_upper_dev_get_rcu() without a NULL check, but that helper
returns NULL when the receiving device has no upper-master adjacency.
The reach guard only checks netif_is_bond_slave(). On bond slave release
bond_upper_dev_unlink() drops the upper-master adjacency before clearing
IFF_SLAVE, so an XDP_TX reaching xdp_master_redirect() in that window
still passes netif_is_bond_slave() while master is already NULL, and
faults on master->flags at offset 0xb0:
BUG: kernel NULL pointer dereference, address: 00000000000000b0
RIP: 0010:xdp_master_redirect (net/core/filter.c:4432)
Call Trace:
xdp_master_redirect (net/core/filter.c:4432)
bpf_prog_run_generic_xdp (include/net/xdp.h:700)
do_xdp_generic (net/core/dev.c:5608)
__netif_receive_skb_one_core (net/core/dev.c:6204)
process_backlog (net/core/dev.c:6319)
__napi_poll (net/core/dev.c:7729)
net_rx_action (net/core/dev.c:7792)
handle_softirqs (kernel/softirq.c:622)
__dev_queue_xmit (include/linux/bottom_half.h:33)
packet_sendmsg (net/packet/af_packet.c:3082)
__sys_sendto (net/socket.c:2252)
Kernel panic - not syncing: Fatal exception in interrupt
The missing check dates back to the original code; commit 1921f91298d1
("net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master")
later added the master->flags read where the fault now lands but kept the
unconditional deref. Check master for NULL before use; a NULL master is
treated the same as one that is not up. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: validate lcns_follow in log_replay conversion
log_replay() converts DIR_PAGE_ENTRY_32 records into DIR_PAGE_ENTRY
records when replaying version 0 restart tables.
During this conversion, the memmove() length is derived directly from
the on-disk lcns_follow field:
memmove(&dp->vcn, &dp0->vcn_low,
2 * sizeof(u64) +
le32_to_cpu(dp->lcns_follow) * sizeof(u64));
check_rstbl() validates restart table structure, but does not constrain
per-entry lcns_follow values relative to the entry size. A malformed
filesystem image can provide an oversized lcns_follow value, causing
the conversion memmove() to access memory beyond the bounds of the
allocated restart table buffer.
The same field is later used to bound iteration over page_lcns[],
so validating lcns_follow during conversion also prevents downstream
out-of-bounds access from the same malformed metadata.
Compute the maximum valid lcns_follow from the already-validated
restart table entry size and reject entries that exceed this bound.
Reuse the existing t16/t32 scratch variables already declared in
log_replay() to avoid introducing new declarations.
[[email protected]: fixed the conflicts] |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: Initialize new folios before use
KMSAN reports an uninitialized value in longest_match_std(), invoked
from ntfs_compress_write(). When new folios are allocated without being
marked uptodate and ni_read_frame() is skipped because the caller expects
the frame to be completely overwritten, some reserved folios may remain
only partially filled, leaving the rest memory uninitialized. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/panthor: fix for dma-fence safe access rules
Commit 506aa8b02a8d6 ("dma-fence: Add safe access helpers and document
the rules") details the dma-fence safe access rules. The most common
culprit is that drm_sched_fence_get_timeline_name may race with
group_free_queue. |
| In the Linux kernel, the following vulnerability has been resolved:
Revert "arm64: zynqmp: Add an OP-TEE node to the device tree"
This reverts commit 06d22ed6b6635b17551f386b50bb5aaff9b75fbe.
OP-TEE logic in U-Boot automatically injects a reserved-memory
node along with optee firmware node to kernel device tree.
The injection logic is dependent on that there is no manually
defined optee node. Having the node in zynqmp.dtsi effectively
breaks OP-TEE's insertion of the reserved-memory node, causing
memory access violations during runtime. |
| In the Linux kernel, the following vulnerability has been resolved:
jfs: nlink overflow in jfs_rename
If nlink is maximal for a directory (-1) and inside that directory you
perform a rename for some child directory (not moving from the parent),
then the nlink of the first directory is first incremented and later
decremented. Normally this is fine, but when nlink = -1 this causes a
wrap around to 0, and then drop_nlink issues a warning.
After applying the patch syzbot no longer issues any warnings. I also
ran some basic fs tests to look for any regressions. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: handle attr_set_size() errors when truncating files
If attr_set_size() fails while truncating down, the error is silently
ignored and the inode may be left in an inconsistent state. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: SOF: ipc4-topology: Correct the allocation size for bytes controls
The size of the data behind of scontrol->ipc_control_data for bytes
controls is:
[1] sizeof(struct sof_ipc4_control_data) + // kernel only struct
[2] sizeof(struct sof_abi_hdr)) + payload
The max_size specifies the size of [2] and it is coming from topology.
Change the function to take this into account and allocate adequate amount
of memory behind scontrol->ipc_control_data.
With the change we will allocate [1] amount more memory to be able to hold
the full size of data. |
| In the Linux kernel, the following vulnerability has been resolved:
rpmsg: core: fix race in driver_override_show() and use core helper
The driver_override_show function reads the driver_override string
without holding the device_lock. However, the store function modifies
and frees the string while holding the device_lock. This creates a race
condition where the string can be freed by the store function while
being read by the show function, leading to a use-after-free.
To fix this, replace the rpmsg_string_attr macro with explicit show and
store functions. The new driver_override_store uses the standard
driver_set_override helper. Since the introduction of
driver_set_override, the comments in include/linux/rpmsg.h have stated
that this helper must be used to set or clear driver_override, but the
implementation was not updated until now.
Because driver_set_override modifies and frees the string while holding
the device_lock, the new driver_override_show now correctly holds the
device_lock during the read operation to prevent the race.
Additionally, since rpmsg_string_attr has only ever been used for
driver_override, removing the macro simplifies the code. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix reservation leak in some error paths when inserting inline extent
If we fail to allocate a path or join a transaction, we return from
__cow_file_range_inline() without freeing the reserved qgroup data,
resulting in a leak. Fix this by ensuring we call btrfs_qgroup_free_data()
in such cases. |
