Linux: >> Linux Kernel >> 3.18.42 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
sch/netem: fix use after free in netem_dequeue
If netem_dequeue() enqueues packet to inner qdisc and that qdisc
returns __NET_XMIT_STOLEN. The packet is dropped but
qdisc_tree_reduce_backlog() is not called to update the parent's
q.qlen, leading to the similar use-after-free as Commit
e04991a48dbaf382 ("netem: fix return value if duplicate enqueue
fails")
Commands to trigger KASAN UaF:
ip link add type dummy
ip link set lo up
ip link set dummy0 up
tc qdisc add dev lo parent root handle 1: drr
tc filter add dev lo parent 1: basic classid 1:1
tc class add dev lo classid 1:1 drr
tc qdisc add dev lo parent 1:1 handle 2: netem
tc qdisc add dev lo parent 2: handle 3: drr
tc filter add dev lo parent 3: basic classid 3:1 action mirred egress
redirect dev dummy0
tc class add dev lo classid 3:1 drr
ping -c1 -W0.01 localhost # Trigger bug
tc class del dev lo classid 1:1
tc class add dev lo classid 1:1 drr
ping -c1 -W0.01 localhost # UaF
CVSS Score
7.8
EPSS Score
0.0
Published
2024-09-18
In the Linux kernel, the following vulnerability has been resolved:
can: bcm: Remove proc entry when dev is unregistered.
syzkaller reported a warning in bcm_connect() below. [0]
The repro calls connect() to vxcan1, removes vxcan1, and calls
connect() with ifindex == 0.
Calling connect() for a BCM socket allocates a proc entry.
Then, bcm_sk(sk)->bound is set to 1 to prevent further connect().
However, removing the bound device resets bcm_sk(sk)->bound to 0
in bcm_notify().
The 2nd connect() tries to allocate a proc entry with the same
name and sets NULL to bcm_sk(sk)->bcm_proc_read, leaking the
original proc entry.
Since the proc entry is available only for connect()ed sockets,
let's clean up the entry when the bound netdev is unregistered.
[0]:
proc_dir_entry 'can-bcm/2456' already registered
WARNING: CPU: 1 PID: 394 at fs/proc/generic.c:376 proc_register+0x645/0x8f0 fs/proc/generic.c:375
Modules linked in:
CPU: 1 PID: 394 Comm: syz-executor403 Not tainted 6.10.0-rc7-g852e42cc2dd4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
RIP: 0010:proc_register+0x645/0x8f0 fs/proc/generic.c:375
Code: 00 00 00 00 00 48 85 ed 0f 85 97 02 00 00 4d 85 f6 0f 85 9f 02 00 00 48 c7 c7 9b cb cf 87 48 89 de 4c 89 fa e8 1c 6f eb fe 90 <0f> 0b 90 90 48 c7 c7 98 37 99 89 e8 cb 7e 22 05 bb 00 00 00 10 48
RSP: 0018:ffa0000000cd7c30 EFLAGS: 00010246
RAX: 9e129be1950f0200 RBX: ff1100011b51582c RCX: ff1100011857cd80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: 0000000000000000 R08: ffd400000000000f R09: ff1100013e78cac0
R10: ffac800000cd7980 R11: ff1100013e12b1f0 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ff1100011a99a2ec
FS: 00007fbd7086f740(0000) GS:ff1100013fd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200071c0 CR3: 0000000118556004 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
proc_create_net_single+0x144/0x210 fs/proc/proc_net.c:220
bcm_connect+0x472/0x840 net/can/bcm.c:1673
__sys_connect_file net/socket.c:2049 [inline]
__sys_connect+0x5d2/0x690 net/socket.c:2066
__do_sys_connect net/socket.c:2076 [inline]
__se_sys_connect net/socket.c:2073 [inline]
__x64_sys_connect+0x8f/0x100 net/socket.c:2073
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7fbd708b0e5d
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 73 9f 1b 00 f7 d8 64 89 01 48
RSP: 002b:00007fff8cd33f08 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fbd708b0e5d
RDX: 0000000000000010 RSI: 0000000020000040 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000040 R09: 0000000000000040
R10: 0000000000000040 R11: 0000000000000246 R12: 00007fff8cd34098
R13: 0000000000401280 R14: 0000000000406de8 R15: 00007fbd70ab9000
</TASK>
remove_proc_entry: removing non-empty directory 'net/can-bcm', leaking at least '2456'
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-18
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check denominator crb_pipes before used
[WHAT & HOW]
A denominator cannot be 0, and is checked before used.
This fixes 2 DIVIDE_BY_ZERO issues reported by Coverity.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-18
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check denominator pbn_div before used
[WHAT & HOW]
A denominator cannot be 0, and is checked before used.
This fixes 1 DIVIDE_BY_ZERO issue reported by Coverity.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-18
In the Linux kernel, the following vulnerability has been resolved:
powerpc/rtas: Prevent Spectre v1 gadget construction in sys_rtas()
Smatch warns:
arch/powerpc/kernel/rtas.c:1932 __do_sys_rtas() warn: potential
spectre issue 'args.args' [r] (local cap)
The 'nargs' and 'nret' locals come directly from a user-supplied
buffer and are used as indexes into a small stack-based array and as
inputs to copy_to_user() after they are subject to bounds checks.
Use array_index_nospec() after the bounds checks to clamp these values
for speculative execution.
CVSS Score
7.1
EPSS Score
0.0
Published
2024-09-18
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Validate function returns
[WHAT & HOW]
Function return values must be checked before data can be used
in subsequent functions.
This fixes 4 CHECKED_RETURN issues reported by Coverity.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-18
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Run DC_LOG_DC after checking link->link_enc
[WHAT]
The DC_LOG_DC should be run after link->link_enc is checked, not before.
This fixes 1 REVERSE_INULL issue reported by Coverity.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-18
In the Linux kernel, the following vulnerability has been resolved:
udf: Avoid excessive partition lengths
Avoid mounting filesystems where the partition would overflow the
32-bits used for block number. Also refuse to mount filesystems where
the partition length is so large we cannot safely index bits in a
block bitmap.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-18
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check UnboundedRequestEnabled's value
CalculateSwathAndDETConfiguration_params_st's UnboundedRequestEnabled
is a pointer (i.e. dml_bool_t *UnboundedRequestEnabled), and thus
if (p->UnboundedRequestEnabled) checks its address, not bool value.
This fixes 1 REVERSE_INULL issue reported by Coverity.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-18
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: protect references to superblock parameters exposed in sysfs
The superblock buffers of nilfs2 can not only be overwritten at runtime
for modifications/repairs, but they are also regularly swapped, replaced
during resizing, and even abandoned when degrading to one side due to
backing device issues. So, accessing them requires mutual exclusion using
the reader/writer semaphore "nilfs->ns_sem".
Some sysfs attribute show methods read this superblock buffer without the
necessary mutual exclusion, which can cause problems with pointer
dereferencing and memory access, so fix it.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-18