Linux: >> Linux Kernel >> 3.18.41 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
media: dvbdev: prevent the risk of out of memory access
The dvbdev contains a static variable used to store dvb minors.
The behavior of it depends if CONFIG_DVB_DYNAMIC_MINORS is set
or not. When not set, dvb_register_device() won't check for
boundaries, as it will rely that a previous call to
dvb_register_adapter() would already be enforcing it.
On a similar way, dvb_device_open() uses the assumption
that the register functions already did the needed checks.
This can be fragile if some device ends using different
calls. This also generate warnings on static check analysers
like Coverity.
So, add explicit guards to prevent potential risk of OOM issues.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-11-19
In the Linux kernel, the following vulnerability has been resolved:
nfs: Fix KMSAN warning in decode_getfattr_attrs()
Fix the following KMSAN warning:
CPU: 1 UID: 0 PID: 7651 Comm: cp Tainted: G B
Tainted: [B]=BAD_PAGE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009)
=====================================================
=====================================================
BUG: KMSAN: uninit-value in decode_getfattr_attrs+0x2d6d/0x2f90
decode_getfattr_attrs+0x2d6d/0x2f90
decode_getfattr_generic+0x806/0xb00
nfs4_xdr_dec_getattr+0x1de/0x240
rpcauth_unwrap_resp_decode+0xab/0x100
rpcauth_unwrap_resp+0x95/0xc0
call_decode+0x4ff/0xb50
__rpc_execute+0x57b/0x19d0
rpc_execute+0x368/0x5e0
rpc_run_task+0xcfe/0xee0
nfs4_proc_getattr+0x5b5/0x990
__nfs_revalidate_inode+0x477/0xd00
nfs_access_get_cached+0x1021/0x1cc0
nfs_do_access+0x9f/0xae0
nfs_permission+0x1e4/0x8c0
inode_permission+0x356/0x6c0
link_path_walk+0x958/0x1330
path_lookupat+0xce/0x6b0
filename_lookup+0x23e/0x770
vfs_statx+0xe7/0x970
vfs_fstatat+0x1f2/0x2c0
__se_sys_newfstatat+0x67/0x880
__x64_sys_newfstatat+0xbd/0x120
x64_sys_call+0x1826/0x3cf0
do_syscall_64+0xd0/0x1b0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The KMSAN warning is triggered in decode_getfattr_attrs(), when calling
decode_attr_mdsthreshold(). It appears that fattr->mdsthreshold is not
initialized.
Fix the issue by initializing fattr->mdsthreshold to NULL in
nfs_fattr_init().
CVSS Score
5.5
EPSS Score
0.0
Published
2024-11-19
In the Linux kernel, the following vulnerability has been resolved:
drm/i915/hdcp: Add encoder check in hdcp2_get_capability
Add encoder check in intel_hdcp2_get_capability to avoid
null pointer error.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-11-19
In the Linux kernel, the following vulnerability has been resolved:
drm/i915/hdcp: Add encoder check in intel_hdcp_get_capability
Sometimes during hotplug scenario or suspend/resume scenario encoder is
not always initialized when intel_hdcp_get_capability add
a check to avoid kernel null pointer dereference.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-11-19
In the Linux kernel, the following vulnerability has been resolved:
io_uring/rw: fix missing NOWAIT check for O_DIRECT start write
When io_uring starts a write, it'll call kiocb_start_write() to bump the
super block rwsem, preventing any freezes from happening while that
write is in-flight. The freeze side will grab that rwsem for writing,
excluding any new writers from happening and waiting for existing writes
to finish. But io_uring unconditionally uses kiocb_start_write(), which
will block if someone is currently attempting to freeze the mount point.
This causes a deadlock where freeze is waiting for previous writes to
complete, but the previous writes cannot complete, as the task that is
supposed to complete them is blocked waiting on starting a new write.
This results in the following stuck trace showing that dependency with
the write blocked starting a new write:
task:fio state:D stack:0 pid:886 tgid:886 ppid:876
Call trace:
__switch_to+0x1d8/0x348
__schedule+0x8e8/0x2248
schedule+0x110/0x3f0
percpu_rwsem_wait+0x1e8/0x3f8
__percpu_down_read+0xe8/0x500
io_write+0xbb8/0xff8
io_issue_sqe+0x10c/0x1020
io_submit_sqes+0x614/0x2110
__arm64_sys_io_uring_enter+0x524/0x1038
invoke_syscall+0x74/0x268
el0_svc_common.constprop.0+0x160/0x238
do_el0_svc+0x44/0x60
el0_svc+0x44/0xb0
el0t_64_sync_handler+0x118/0x128
el0t_64_sync+0x168/0x170
INFO: task fsfreeze:7364 blocked for more than 15 seconds.
Not tainted 6.12.0-rc5-00063-g76aaf945701c #7963
with the attempting freezer stuck trying to grab the rwsem:
task:fsfreeze state:D stack:0 pid:7364 tgid:7364 ppid:995
Call trace:
__switch_to+0x1d8/0x348
__schedule+0x8e8/0x2248
schedule+0x110/0x3f0
percpu_down_write+0x2b0/0x680
freeze_super+0x248/0x8a8
do_vfs_ioctl+0x149c/0x1b18
__arm64_sys_ioctl+0xd0/0x1a0
invoke_syscall+0x74/0x268
el0_svc_common.constprop.0+0x160/0x238
do_el0_svc+0x44/0x60
el0_svc+0x44/0xb0
el0t_64_sync_handler+0x118/0x128
el0t_64_sync+0x168/0x170
Fix this by having the io_uring side honor IOCB_NOWAIT, and only attempt a
blocking grab of the super block rwsem if it isn't set. For normal issue
where IOCB_NOWAIT would always be set, this returns -EAGAIN which will
have io_uring core issue a blocking attempt of the write. That will in
turn also get completions run, ensuring forward progress.
Since freezing requires CAP_SYS_ADMIN in the first place, this isn't
something that can be triggered by a regular user.
CVSS Score
4.4
EPSS Score
0.0
Published
2024-11-19
In the Linux kernel, the following vulnerability has been resolved:
net/sched: stop qdisc_tree_reduce_backlog on TC_H_ROOT
In qdisc_tree_reduce_backlog, Qdiscs with major handle ffff: are assumed
to be either root or ingress. This assumption is bogus since it's valid
to create egress qdiscs with major handle ffff:
Budimir Markovic found that for qdiscs like DRR that maintain an active
class list, it will cause a UAF with a dangling class pointer.
In 066a3b5b2346, the concern was to avoid iterating over the ingress
qdisc since its parent is itself. The proper fix is to stop when parent
TC_H_ROOT is reached because the only way to retrieve ingress is when a
hierarchy which does not contain a ffff: major handle call into
qdisc_lookup with TC_H_MAJ(TC_H_ROOT).
In the scenario where major ffff: is an egress qdisc in any of the tree
levels, the updates will also propagate to TC_H_ROOT, which then the
iteration must stop.
net/sched/sch_api.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
CVSS Score
7.8
EPSS Score
0.0
Published
2024-11-19
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: prevent NULL pointer dereference if ATIF is not supported
acpi_evaluate_object() may return AE_NOT_FOUND (failure), which
would result in dereferencing buffer.pointer (obj) while being NULL.
Although this case may be unrealistic for the current code, it is
still better to protect against possible bugs.
Bail out also when status is AE_NOT_FOUND.
This fixes 1 FORWARD_NULL issue reported by Coverity
Report: CID 1600951: Null pointer dereferences (FORWARD_NULL)
(cherry picked from commit 91c9e221fe2553edf2db71627d8453f083de87a1)
CVSS Score
5.5
EPSS Score
0.0
Published
2024-11-19
In the Linux kernel, the following vulnerability has been resolved:
ipv4: ip_tunnel: Fix suspicious RCU usage warning in ip_tunnel_find()
The per-netns IP tunnel hash table is protected by the RTNL mutex and
ip_tunnel_find() is only called from the control path where the mutex is
taken.
Add a lockdep expression to hlist_for_each_entry_rcu() in
ip_tunnel_find() in order to validate that the mutex is held and to
silence the suspicious RCU usage warning [1].
[1]
WARNING: suspicious RCU usage
6.12.0-rc3-custom-gd95d9a31aceb #139 Not tainted
-----------------------------
net/ipv4/ip_tunnel.c:221 RCU-list traversed in non-reader section!!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by ip/362:
#0: ffffffff86fc7cb0 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x377/0xf60
stack backtrace:
CPU: 12 UID: 0 PID: 362 Comm: ip Not tainted 6.12.0-rc3-custom-gd95d9a31aceb #139
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
<TASK>
dump_stack_lvl+0xba/0x110
lockdep_rcu_suspicious.cold+0x4f/0xd6
ip_tunnel_find+0x435/0x4d0
ip_tunnel_newlink+0x517/0x7a0
ipgre_newlink+0x14c/0x170
__rtnl_newlink+0x1173/0x19c0
rtnl_newlink+0x6c/0xa0
rtnetlink_rcv_msg+0x3cc/0xf60
netlink_rcv_skb+0x171/0x450
netlink_unicast+0x539/0x7f0
netlink_sendmsg+0x8c1/0xd80
____sys_sendmsg+0x8f9/0xc20
___sys_sendmsg+0x197/0x1e0
__sys_sendmsg+0x122/0x1f0
do_syscall_64+0xbb/0x1d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
CVSS Score
5.5
EPSS Score
0.0
Published
2024-11-19
In the Linux kernel, the following vulnerability has been resolved:
sctp: properly validate chunk size in sctp_sf_ootb()
A size validation fix similar to that in Commit 50619dbf8db7 ("sctp: add
size validation when walking chunks") is also required in sctp_sf_ootb()
to address a crash reported by syzbot:
BUG: KMSAN: uninit-value in sctp_sf_ootb+0x7f5/0xce0 net/sctp/sm_statefuns.c:3712
sctp_sf_ootb+0x7f5/0xce0 net/sctp/sm_statefuns.c:3712
sctp_do_sm+0x181/0x93d0 net/sctp/sm_sideeffect.c:1166
sctp_endpoint_bh_rcv+0xc38/0xf90 net/sctp/endpointola.c:407
sctp_inq_push+0x2ef/0x380 net/sctp/inqueue.c:88
sctp_rcv+0x3831/0x3b20 net/sctp/input.c:243
sctp4_rcv+0x42/0x50 net/sctp/protocol.c:1159
ip_protocol_deliver_rcu+0xb51/0x13d0 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x336/0x500 net/ipv4/ip_input.c:233
CVSS Score
5.5
EPSS Score
0.0
Published
2024-11-19
In the Linux kernel, the following vulnerability has been resolved:
security/keys: fix slab-out-of-bounds in key_task_permission
KASAN reports an out of bounds read:
BUG: KASAN: slab-out-of-bounds in __kuid_val include/linux/uidgid.h:36
BUG: KASAN: slab-out-of-bounds in uid_eq include/linux/uidgid.h:63 [inline]
BUG: KASAN: slab-out-of-bounds in key_task_permission+0x394/0x410
security/keys/permission.c:54
Read of size 4 at addr ffff88813c3ab618 by task stress-ng/4362
CPU: 2 PID: 4362 Comm: stress-ng Not tainted 5.10.0-14930-gafbffd6c3ede #15
Call Trace:
__dump_stack lib/dump_stack.c:82 [inline]
dump_stack+0x107/0x167 lib/dump_stack.c:123
print_address_description.constprop.0+0x19/0x170 mm/kasan/report.c:400
__kasan_report.cold+0x6c/0x84 mm/kasan/report.c:560
kasan_report+0x3a/0x50 mm/kasan/report.c:585
__kuid_val include/linux/uidgid.h:36 [inline]
uid_eq include/linux/uidgid.h:63 [inline]
key_task_permission+0x394/0x410 security/keys/permission.c:54
search_nested_keyrings+0x90e/0xe90 security/keys/keyring.c:793
This issue was also reported by syzbot.
It can be reproduced by following these steps(more details [1]):
1. Obtain more than 32 inputs that have similar hashes, which ends with the
pattern '0xxxxxxxe6'.
2. Reboot and add the keys obtained in step 1.
The reproducer demonstrates how this issue happened:
1. In the search_nested_keyrings function, when it iterates through the
slots in a node(below tag ascend_to_node), if the slot pointer is meta
and node->back_pointer != NULL(it means a root), it will proceed to
descend_to_node. However, there is an exception. If node is the root,
and one of the slots points to a shortcut, it will be treated as a
keyring.
2. Whether the ptr is keyring decided by keyring_ptr_is_keyring function.
However, KEYRING_PTR_SUBTYPE is 0x2UL, the same as
ASSOC_ARRAY_PTR_SUBTYPE_MASK.
3. When 32 keys with the similar hashes are added to the tree, the ROOT
has keys with hashes that are not similar (e.g. slot 0) and it splits
NODE A without using a shortcut. When NODE A is filled with keys that
all hashes are xxe6, the keys are similar, NODE A will split with a
shortcut. Finally, it forms the tree as shown below, where slot 6 points
to a shortcut.
NODE A
+------>+---+
ROOT | | 0 | xxe6
+---+ | +---+
xxxx | 0 | shortcut : : xxe6
+---+ | +---+
xxe6 : : | | | xxe6
+---+ | +---+
| 6 |---+ : : xxe6
+---+ +---+
xxe6 : : | f | xxe6
+---+ +---+
xxe6 | f |
+---+
4. As mentioned above, If a slot(slot 6) of the root points to a shortcut,
it may be mistakenly transferred to a key*, leading to a read
out-of-bounds read.
To fix this issue, one should jump to descend_to_node if the ptr is a
shortcut, regardless of whether the node is root or not.
[1] https://lore.kernel.org/linux-kernel/1cfa878e-8c7b-4570-8606-21daf5e13ce7@huaweicloud.com/
[jarkko: tweaked the commit message a bit to have an appropriate closes
tag.]
CVSS Score
7.1
EPSS Score
0.001
Published
2024-11-19