bridge: stp: Fix a potential use-after-free when deleting a bridge
In the Linux kernel, the following vulnerability has been resolved:
bridge: stp: Fix a potential use-after-free when deleting a bridge
The three STP timers are not supposed to be armed while the bridge is
administratively down. They are synchronously deactivated when the
bridge is put administratively down and the various call sites check for
'IFF_UP' before arming them.
This check is missing from br_topology_change_detection() and it is
possible to engineer a situation in which the topology change timer is
armed while the bridge is administratively down, resulting in a
use-after-free [1] when the bridge is deleted.
Fix by adding the miss
sctp: fix addr_wq_timer race in sctp_free_addr_wq()
In the Linux kernel, the following vulnerability has been resolved:
sctp: fix addr_wq_timer race in sctp_free_addr_wq()
sctp_free_addr_wq() previously removed addr_wq_timer using timer_delete()
while holding addr_wq_lock. However, timer_delete() does not guarantee that
a currently running timer handler has completed.
This allows a race with sctp_addr_wq_timeout_handler(), where the handler
may still run after addr_waitq has been freed, acquire addr_wq_lock, and
access freed memory, leading to a use-after-free.
Fix this by calling timer_shutdown_sync() before taking addr_wq_lock. This
guarantees that any in-flight timer handler has finish
afs: Fix reinitialisation of the inode, in particular ->lock_work
In the Linux kernel, the following vulnerability has been resolved:
afs: Fix reinitialisation of the inode, in particular ->lock_work
It seems that initalising afs_vnode::lock_work a single time in the slab's
init function isn't sufficient for work_structs. This results in the
DEBUG_OBJECTS debugging stuff producing a warning occasionally when running
the generic/131 xfstest:
ODEBUG: activate not available (active state 0) object: 0000000016d8760f object type: work_struct hint: afs_lock_work+0x0/0x220
WARNING: lib/debugobjects.c:629 at debug_print_object+0x4b/0x90, CPU#3: locktest/7695
...
CPU: 3 UID: 0 PID: 7695 Comm: locktest Tainte
In the Linux kernel, the following vulnerability has been resolved:
gue: validate REMCSUM private option length
GUE private flags can indicate that remote checksum offload metadata is
present. The private flags field itself is accounted for by
guehdr_flags_len(), but guehdr_priv_flags_len() currently returns 0 even
when GUE_PFLAG_REMCSUM is set.
This lets a packet with only the private flags field pass
validate_gue_flags(), after which gue_remcsum() and gue_gro_remcsum()
read the missing REMCSUM start/offset fields from the following bytes.
Account for GUE_PLEN_REMCSUM when GUE_PFLAG_REMCSUM is present so that
malformed packets are reject
In the Linux kernel, the following vulnerability has been resolved:
netfilter: xt_u32: reject invalid shift counts
u32_match_it() executes rule-supplied shift operands on a 32-bit
value. A malformed u32 rule can provide a shift count of 32 or more,
triggering an undefined shift out-of-bounds during packet evaluation.
Validate XT_U32_LEFTSH and XT_U32_RIGHTSH operands in
u32_mt_checkentry() and reject malformed rules before they reach the
packet path.
netfilter: ip6tables: mark malformed IPv6 extension headers for hotdrop
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ip6tables: mark malformed IPv6 extension headers for hotdrop
The ah, hbh and rt matches check that the fixed extension header is
present, then use the header length field to derive the advertised
extension header length for matching.
For the ah match, add the missing advertised-length check. For hbh
and rt, update the existing advertised-length checks. In all three
cases, set hotdrop to true before returning false when the advertised
extension header length exceeds the available skb data.
Returning false treats the packet as a rule mismatch. Set hotdrop to
true
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: 6lowpan: avoid untracked enable work
lowpan_enable_set() allocates a temporary work item and schedules
do_enable_set() on system_wq, then returns to debugfs. The debugfs active
operation has ended at that point, but the worker still executes module
text and manipulates enable_6lowpan and listen_chan.
bt_6lowpan_exit() removes the debugfs files and immediately closes and
puts listen_chan. It has no pointer to the queued work item, so it cannot
cancel or flush it before tearing down the state that the worker uses.
The buggy scenario involves two paths, with each
Bluetooth: 6lowpan: hold L2CAP conn across debugfs control
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: 6lowpan: hold L2CAP conn across debugfs control
get_l2cap_conn() looks up an LE hci_conn under hdev protection, but
then drops that protection before reading hcon->l2cap_data and before
lowpan_control_write() later dereferences conn->hcon. A disconnect or
device close can tear down the same L2CAP connection in that window.
The buggy scenario involves two paths, with each column showing the order
within that path:
6LoWPAN control write: HCI disconnect/device close:
1. get_l2cap_conn() finds hcon 1. hci_disconn_cfm() dispatches
and hcon-
ipv4: igmp: Fix potential UAF in igmp_gq_start_timer()
In the Linux kernel, the following vulnerability has been resolved:
ipv4: igmp: Fix potential UAF in igmp_gq_start_timer()
A race condition exists between device teardown (inetdev_destroy) and
incoming IGMP query processing (igmp_rcv), leading to a Use-After-Free
in the IGMP timer callback.
During device destruction, inetdev_destroy() drops the primary reference
to in_device, which can drop its refcount to 0. The actual freeing of
in_device memory is deferred via RCU (using call_rcu()).
Concurrently, igmp_rcv() runs under RCU read lock and obtains the
in_device pointer. Because the memory is RCU-protected, CPU-0 can safely
dereference in_
ipv6: mcast: Fix potential UAF in MLD delayed work
In the Linux kernel, the following vulnerability has been resolved:
ipv6: mcast: Fix potential UAF in MLD delayed work
A race condition exists between device teardown and incoming MLD query
processing, leading to a Use-After-Free in the MLD delayed work.
During device destruction, the primary reference to inet6_dev is dropped,
which can drop its refcount to 0. The actual freeing of inet6_dev memory
is deferred via RCU.
Concurrently, the packet receive path runs under RCU read lock and obtains
the inet6_dev pointer. Because the memory is RCU-protected, CPU-0 can
safely dereference inet6_dev even if its refcount has hit 0.
However, if CPU-
ipv4: igmp: Fix potential memory leaks in igmp_mod_timer() and igmp_stop_timer()
In the Linux kernel, the following vulnerability has been resolved:
ipv4: igmp: Fix potential memory leaks in igmp_mod_timer() and igmp_stop_timer()
When a timer is deleted and not re-armed in igmp_mod_timer(), or stopped
in igmp_stop_timer(), the code currently decrements the reference counter
of the multicast list entry @im using refcount_dec(&im->refcnt).
However, both functions can be called from the RCU reader path:
- igmp_mod_timer() via igmp_heard_query() -> for_each_pmc_rcu()
- igmp_stop_timer() via igmp_rcv() -> igmp_heard_report()
If the group im was concurrently removed from the list by ip_mc_dec_group(),
its reference count mi
ipvs: ensure inner headers in ICMP errors are in headroom
In the Linux kernel, the following vulnerability has been resolved:
ipvs: ensure inner headers in ICMP errors are in headroom
Sashiko points out that after stripping the outer headers
with pskb_pull() we should ensure the inner IP headers
in ICMP errors from tunnels are present in the skb headroom
for functions like ipv4_update_pmtu(), icmp_send() and
IP_VS_DBG().
Also, add more checks for the length of the inner headers.
dm era: fix NULL pointer dereference in metadata_open()
In the Linux kernel, the following vulnerability has been resolved:
dm era: fix NULL pointer dereference in metadata_open()
metadata_open() returns NULL when kzalloc_obj() fails, but the
caller era_ctr() only checks IS_ERR(md). Since IS_ERR(NULL)
returns false, the NULL pointer is treated as a valid result
and later assigned to era->md, leading to a NULL pointer
dereference when the metadata is accessed.
Fix this by returning ERR_PTR(-ENOMEM) on allocation failure,
consistent with dm-cache-metadata.c, dm-thin-metadata.c, and
dm-clone-metadata.c which all use ERR_PTR(-ENOMEM) for the
same pattern.
net: atm: reject out-of-range traffic classes in QoS validation
In the Linux kernel, the following vulnerability has been resolved:
net: atm: reject out-of-range traffic classes in QoS validation
Reject ATM traffic classes above ATM_ANYCLASS in check_tp().
SO_ATMQOS stores the supplied QoS after check_qos() succeeds, so
accepting larger values leaves invalid traffic_class values in
vcc->qos.
That bad state later reaches pvc_info(), which indexes class_name[]
with vcc->qos.{rx,tp}.traffic_class. Values above ATM_ANYCLASS cause
an out-of-bounds read when /proc/net/atm/pvc is read.
Tighten the existing QoS validation so invalid traffic_class values
are rejected at the point where user supplied QoS is acc
KVM: x86: Ignore pending PV EOI if the vCPU has since disabled PV EOIs
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Ignore pending PV EOI if the vCPU has since disabled PV EOIs
Ignore KVM's internal "service pending PV EOI" request if the vCPU has
disabled PV EOIs since the request was made. Asserting that PV EOIs are
enabled can fail if reading guest memory in pv_eoi_get_user() fails, i.e.
if pv_eoi_test_and_clr_pending() bails early, *and* the vCPU also disables
PV EOIs.
kernel BUG at arch/x86/kvm/lapic.c:3338!
Oops: invalid opcode: 0000 [#1] SMP
CPU: 4 UID: 1000 PID: 890 Comm: pv_eoi_test Not tainted 7.0.0-d585aa5894d8-vm #337 PREEMPT
Hardware name: QEMU Standard P
fbdev: radeon: fix potential memory leak in radeonfb_pci_register()
In the Linux kernel, the following vulnerability has been resolved:
fbdev: radeon: fix potential memory leak in radeonfb_pci_register()
The function radeonfb_pci_register() allocates memory for modelist
(by calling radeon_check_modes() which calls fb_add_videomode()).
The memory is appended to info->modelist, but is not freed in subsequent
error paths. Fix this by calling fb_destroy_modelist().
fbdev: i740fb: fix potential memory leak in i740fb_probe()
In the Linux kernel, the following vulnerability has been resolved:
fbdev: i740fb: fix potential memory leak in i740fb_probe()
In i740fb_probe(), the memory allocated in fb_videomode_to_modelist()
for modelist is not freed in the error paths. Fix that by calling
fb_destroy_modelist().
fbdev: s3fb: fix potential memory leak in s3_pci_probe()
In the Linux kernel, the following vulnerability has been resolved:
fbdev: s3fb: fix potential memory leak in s3_pci_probe()
In s3_pci_probe(), the memory allocated for modelist using
fb_videomode_to_modelist() is not freed in subsequent error paths.
Fix that by calling fb_destroy_modelist()
fbdev: uvesafb: fix potential memory leak in uvesafb_probe()
In the Linux kernel, the following vulnerability has been resolved:
fbdev: uvesafb: fix potential memory leak in uvesafb_probe()
Due to an incorrect goto label, memory allocated for modedb and modelist
in uvesafb_vbe_init() is not freed in some error paths. Fix this by
updating the goto label.
fbdev: tdfxfb: fix potential memory leak in tdfxfb_probe()
In the Linux kernel, the following vulnerability has been resolved:
fbdev: tdfxfb: fix potential memory leak in tdfxfb_probe()
In tdfxfb_probe(), the memory allocated for modelist using
fb_videomode_to_modelist() when CONFIG_FB_3DFX_I2C is defined, is not
freed in the subsequent error paths.
Fix that by calling fb_destroy_modelist().