Linux: >> Linux Kernel >> 2.6.20.12 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
NFSv4.0: Fix a use-after-free problem in the asynchronous open()
Yang Erkun reports that when two threads are opening files at the same
time, and are forced to abort before a reply is seen, then the call to
nfs_release_seqid() in nfs4_opendata_free() can result in a
use-after-free of the pointer to the defunct rpc task of the other
thread.
The fix is to ensure that if the RPC call is aborted before the call to
nfs_wait_on_sequence() is complete, then we must call nfs_release_seqid()
in nfs4_open_release() before the rpc_task is freed.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-12-27
In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: make sure cache entry active before cache_show
The function `c_show` was called with protection from RCU. This only
ensures that `cp` will not be freed. Therefore, the reference count for
`cp` can drop to zero, which will trigger a refcount use-after-free
warning when `cache_get` is called. To resolve this issue, use
`cache_get_rcu` to ensure that `cp` remains active.
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 7 PID: 822 at lib/refcount.c:25
refcount_warn_saturate+0xb1/0x120
CPU: 7 UID: 0 PID: 822 Comm: cat Not tainted 6.12.0-rc3+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
RIP: 0010:refcount_warn_saturate+0xb1/0x120
Call Trace:
<TASK>
c_show+0x2fc/0x380 [sunrpc]
seq_read_iter+0x589/0x770
seq_read+0x1e5/0x270
proc_reg_read+0xe1/0x140
vfs_read+0x125/0x530
ksys_read+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e
CVSS Score
7.8
EPSS Score
0.0
Published
2024-12-27
In the Linux kernel, the following vulnerability has been resolved:
net: sched: fix ordering of qlen adjustment
Changes to sch->q.qlen around qdisc_tree_reduce_backlog() need to happen
_before_ a call to said function because otherwise it may fail to notify
parent qdiscs when the child is about to become empty.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-12-27
In the Linux kernel, the following vulnerability has been resolved:
sh: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK
When CONFIG_CPUMASK_OFFSTACK and CONFIG_DEBUG_PER_CPU_MAPS are selected,
cpu_max_bits_warn() generates a runtime warning similar as below when
showing /proc/cpuinfo. Fix this by using nr_cpu_ids (the runtime limit)
instead of NR_CPUS to iterate CPUs.
[ 3.052463] ------------[ cut here ]------------
[ 3.059679] WARNING: CPU: 3 PID: 1 at include/linux/cpumask.h:108 show_cpuinfo+0x5e8/0x5f0
[ 3.070072] Modules linked in: efivarfs autofs4
[ 3.076257] CPU: 0 PID: 1 Comm: systemd Not tainted 5.19-rc5+ #1052
[ 3.099465] Stack : 9000000100157b08 9000000000f18530 9000000000cf846c 9000000100154000
[ 3.109127] 9000000100157a50 0000000000000000 9000000100157a58 9000000000ef7430
[ 3.118774] 90000001001578e8 0000000000000040 0000000000000020 ffffffffffffffff
[ 3.128412] 0000000000aaaaaa 1ab25f00eec96a37 900000010021de80 900000000101c890
[ 3.138056] 0000000000000000 0000000000000000 0000000000000000 0000000000aaaaaa
[ 3.147711] ffff8000339dc220 0000000000000001 0000000006ab4000 0000000000000000
[ 3.157364] 900000000101c998 0000000000000004 9000000000ef7430 0000000000000000
[ 3.167012] 0000000000000009 000000000000006c 0000000000000000 0000000000000000
[ 3.176641] 9000000000d3de08 9000000001639390 90000000002086d8 00007ffff0080286
[ 3.186260] 00000000000000b0 0000000000000004 0000000000000000 0000000000071c1c
[ 3.195868] ...
[ 3.199917] Call Trace:
[ 3.203941] [<90000000002086d8>] show_stack+0x38/0x14c
[ 3.210666] [<9000000000cf846c>] dump_stack_lvl+0x60/0x88
[ 3.217625] [<900000000023d268>] __warn+0xd0/0x100
[ 3.223958] [<9000000000cf3c90>] warn_slowpath_fmt+0x7c/0xcc
[ 3.231150] [<9000000000210220>] show_cpuinfo+0x5e8/0x5f0
[ 3.238080] [<90000000004f578c>] seq_read_iter+0x354/0x4b4
[ 3.245098] [<90000000004c2e90>] new_sync_read+0x17c/0x1c4
[ 3.252114] [<90000000004c5174>] vfs_read+0x138/0x1d0
[ 3.258694] [<90000000004c55f8>] ksys_read+0x70/0x100
[ 3.265265] [<9000000000cfde9c>] do_syscall+0x7c/0x94
[ 3.271820] [<9000000000202fe4>] handle_syscall+0xc4/0x160
[ 3.281824] ---[ end trace 8b484262b4b8c24c ]---
CVSS Score
5.5
EPSS Score
0.0
Published
2024-12-27
CVE-2024-53150
In the Linux kernel, the following vulnerability has been resolved:
ALSA: usb-audio: Fix out of bounds reads when finding clock sources
The current USB-audio driver code doesn't check bLength of each
descriptor at traversing for clock descriptors. That is, when a
device provides a bogus descriptor with a shorter bLength, the driver
might hit out-of-bounds reads.
For addressing it, this patch adds sanity checks to the validator
functions for the clock descriptor traversal. When the descriptor
length is shorter than expected, it's skipped in the loop.
For the clock source and clock multiplier descriptors, we can just
check bLength against the sizeof() of each descriptor type.
OTOH, the clock selector descriptor of UAC2 and UAC3 has an array
of bNrInPins elements and two more fields at its tail, hence those
have to be checked in addition to the sizeof() check.
Known exploited
CVSS Score
7.1
EPSS Score
0.011
Published
2024-12-24
In the Linux kernel, the following vulnerability has been resolved:
NFSD: Prevent a potential integer overflow
If the tag length is >= U32_MAX - 3 then the "length + 4" addition
can result in an integer overflow. Address this by splitting the
decoding into several steps so that decode_cb_compound4res() does
not have to perform arithmetic on the unsafe length value.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-12-24
In the Linux kernel, the following vulnerability has been resolved:
x86/xen: don't do PV iret hypercall through hypercall page
Instead of jumping to the Xen hypercall page for doing the iret
hypercall, directly code the required sequence in xen-asm.S.
This is done in preparation of no longer using hypercall page at all,
as it has shown to cause problems with speculation mitigations.
This is part of XSA-466 / CVE-2024-53241.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-12-24
In the Linux kernel, the following vulnerability has been resolved:
initramfs: avoid filename buffer overrun
The initramfs filename field is defined in
Documentation/driver-api/early-userspace/buffer-format.rst as:
37 cpio_file := ALGN(4) + cpio_header + filename + "\0" + ALGN(4) + data
...
55 ============= ================== =========================
56 Field name Field size Meaning
57 ============= ================== =========================
...
70 c_namesize 8 bytes Length of filename, including final \0
When extracting an initramfs cpio archive, the kernel's do_name() path
handler assumes a zero-terminated path at @collected, passing it
directly to filp_open() / init_mkdir() / init_mknod().
If a specially crafted cpio entry carries a non-zero-terminated filename
and is followed by uninitialized memory, then a file may be created with
trailing characters that represent the uninitialized memory. The ability
to create an initramfs entry would imply already having full control of
the system, so the buffer overrun shouldn't be considered a security
vulnerability.
Append the output of the following bash script to an existing initramfs
and observe any created /initramfs_test_fname_overrunAA* path. E.g.
./reproducer.sh | gzip >> /myinitramfs
It's easiest to observe non-zero uninitialized memory when the output is
gzipped, as it'll overflow the heap allocated @out_buf in __gunzip(),
rather than the initrd_start+initrd_size block.
---- reproducer.sh ----
nilchar="A" # change to "\0" to properly zero terminate / pad
magic="070701"
ino=1
mode=$(( 0100777 ))
uid=0
gid=0
nlink=1
mtime=1
filesize=0
devmajor=0
devminor=1
rdevmajor=0
rdevminor=0
csum=0
fname="initramfs_test_fname_overrun"
namelen=$(( ${#fname} + 1 )) # plus one to account for terminator
printf "%s%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%s" \
$magic $ino $mode $uid $gid $nlink $mtime $filesize \
$devmajor $devminor $rdevmajor $rdevminor $namelen $csum $fname
termpadlen=$(( 1 + ((4 - ((110 + $namelen) & 3)) % 4) ))
printf "%.s${nilchar}" $(seq 1 $termpadlen)
---- reproducer.sh ----
Symlink filename fields handled in do_symlink() won't overrun past the
data segment, due to the explicit zero-termination of the symlink
target.
Fix filename buffer overrun by aborting the initramfs FSM if any cpio
entry doesn't carry a zero-terminator at the expected (name_len - 1)
offset.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-12-06
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Handle dml allocation failure to avoid crash
[Why]
In the case where a dml allocation fails for any reason, the
current state's dml contexts would no longer be valid. Then
subsequent calls dc_state_copy_internal would shallow copy
invalid memory and if the new state was released, a double
free would occur.
[How]
Reset dml pointers in new_state to NULL and avoid invalid
pointer
(cherry picked from commit bcafdc61529a48f6f06355d78eb41b3aeda5296c)
CVSS Score
7.8
EPSS Score
0.0
Published
2024-12-04
In the Linux kernel, the following vulnerability has been resolved:
vdpa: solidrun: Fix UB bug with devres
In psnet_open_pf_bar() and snet_open_vf_bar() a string later passed to
pcim_iomap_regions() is placed on the stack. Neither
pcim_iomap_regions() nor the functions it calls copy that string.
Should the string later ever be used, this, consequently, causes
undefined behavior since the stack frame will by then have disappeared.
Fix the bug by allocating the strings on the heap through
devm_kasprintf().
CVSS Score
7.8
EPSS Score
0.0
Published
2024-12-04