Security Vulnerabilities - CVEs Published In August 2024
In the Linux kernel, the following vulnerability has been resolved:
thermal: int340x: fix memory leak in int3400_notify()
It is easy to hit the below memory leaks in my TigerLake platform:
unreferenced object 0xffff927c8b91dbc0 (size 32):
comm "kworker/0:2", pid 112, jiffies 4294893323 (age 83.604s)
hex dump (first 32 bytes):
4e 41 4d 45 3d 49 4e 54 33 34 30 30 20 54 68 65 NAME=INT3400 The
72 6d 61 6c 00 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 rmal.kkkkkkkkkk.
backtrace:
[<ffffffff9c502c3e>] __kmalloc_track_caller+0x2fe/0x4a0
[<ffffffff9c7b7c15>] kvasprintf+0x65/0xd0
[<ffffffff9c7b7d6e>] kasprintf+0x4e/0x70
[<ffffffffc04cb662>] int3400_notify+0x82/0x120 [int3400_thermal]
[<ffffffff9c8b7358>] acpi_ev_notify_dispatch+0x54/0x71
[<ffffffff9c88f1a7>] acpi_os_execute_deferred+0x17/0x30
[<ffffffff9c2c2c0a>] process_one_work+0x21a/0x3f0
[<ffffffff9c2c2e2a>] worker_thread+0x4a/0x3b0
[<ffffffff9c2cb4dd>] kthread+0xfd/0x130
[<ffffffff9c201c1f>] ret_from_fork+0x1f/0x30
Fix it by calling kfree() accordingly.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-22
In the Linux kernel, the following vulnerability has been resolved:
RDMA/cma: Do not change route.addr.src_addr outside state checks
If the state is not idle then resolve_prepare_src() should immediately
fail and no change to global state should happen. However, it
unconditionally overwrites the src_addr trying to build a temporary any
address.
For instance if the state is already RDMA_CM_LISTEN then this will corrupt
the src_addr and would cause the test in cma_cancel_operation():
if (cma_any_addr(cma_src_addr(id_priv)) && !id_priv->cma_dev)
Which would manifest as this trace from syzkaller:
BUG: KASAN: use-after-free in __list_add_valid+0x93/0xa0 lib/list_debug.c:26
Read of size 8 at addr ffff8881546491e0 by task syz-executor.1/32204
CPU: 1 PID: 32204 Comm: syz-executor.1 Not tainted 5.12.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x141/0x1d7 lib/dump_stack.c:120
print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232
__kasan_report mm/kasan/report.c:399 [inline]
kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
__list_add_valid+0x93/0xa0 lib/list_debug.c:26
__list_add include/linux/list.h:67 [inline]
list_add_tail include/linux/list.h:100 [inline]
cma_listen_on_all drivers/infiniband/core/cma.c:2557 [inline]
rdma_listen+0x787/0xe00 drivers/infiniband/core/cma.c:3751
ucma_listen+0x16a/0x210 drivers/infiniband/core/ucma.c:1102
ucma_write+0x259/0x350 drivers/infiniband/core/ucma.c:1732
vfs_write+0x28e/0xa30 fs/read_write.c:603
ksys_write+0x1ee/0x250 fs/read_write.c:658
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae
This is indicating that an rdma_id_private was destroyed without doing
cma_cancel_listens().
Instead of trying to re-use the src_addr memory to indirectly create an
any address derived from the dst build one explicitly on the stack and
bind to that as any other normal flow would do. rdma_bind_addr() will copy
it over the src_addr once it knows the state is valid.
This is similar to commit bc0bdc5afaa7 ("RDMA/cma: Do not change
route.addr.src_addr.ss_family")
CVSS Score
7.8
EPSS Score
0.0
Published
2024-08-22
In the Linux kernel, the following vulnerability has been resolved:
btrfs: get rid of warning on transaction commit when using flushoncommit
When using the flushoncommit mount option, during almost every transaction
commit we trigger a warning from __writeback_inodes_sb_nr():
$ cat fs/fs-writeback.c:
(...)
static void __writeback_inodes_sb_nr(struct super_block *sb, ...
{
(...)
WARN_ON(!rwsem_is_locked(&sb->s_umount));
(...)
}
(...)
The trace produced in dmesg looks like the following:
[947.473890] WARNING: CPU: 5 PID: 930 at fs/fs-writeback.c:2610 __writeback_inodes_sb_nr+0x7e/0xb3
[947.481623] Modules linked in: nfsd nls_cp437 cifs asn1_decoder cifs_arc4 fscache cifs_md4 ipmi_ssif
[947.489571] CPU: 5 PID: 930 Comm: btrfs-transacti Not tainted 95.16.3-srb-asrock-00001-g36437ad63879 #186
[947.497969] RIP: 0010:__writeback_inodes_sb_nr+0x7e/0xb3
[947.502097] Code: 24 10 4c 89 44 24 18 c6 (...)
[947.519760] RSP: 0018:ffffc90000777e10 EFLAGS: 00010246
[947.523818] RAX: 0000000000000000 RBX: 0000000000963300 RCX: 0000000000000000
[947.529765] RDX: 0000000000000000 RSI: 000000000000fa51 RDI: ffffc90000777e50
[947.535740] RBP: ffff888101628a90 R08: ffff888100955800 R09: ffff888100956000
[947.541701] R10: 0000000000000002 R11: 0000000000000001 R12: ffff888100963488
[947.547645] R13: ffff888100963000 R14: ffff888112fb7200 R15: ffff888100963460
[947.553621] FS: 0000000000000000(0000) GS:ffff88841fd40000(0000) knlGS:0000000000000000
[947.560537] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[947.565122] CR2: 0000000008be50c4 CR3: 000000000220c000 CR4: 00000000001006e0
[947.571072] Call Trace:
[947.572354] <TASK>
[947.573266] btrfs_commit_transaction+0x1f1/0x998
[947.576785] ? start_transaction+0x3ab/0x44e
[947.579867] ? schedule_timeout+0x8a/0xdd
[947.582716] transaction_kthread+0xe9/0x156
[947.585721] ? btrfs_cleanup_transaction.isra.0+0x407/0x407
[947.590104] kthread+0x131/0x139
[947.592168] ? set_kthread_struct+0x32/0x32
[947.595174] ret_from_fork+0x22/0x30
[947.597561] </TASK>
[947.598553] ---[ end trace 644721052755541c ]---
This is because we started using writeback_inodes_sb() to flush delalloc
when committing a transaction (when using -o flushoncommit), in order to
avoid deadlocks with filesystem freeze operations. This change was made
by commit ce8ea7cc6eb313 ("btrfs: don't call btrfs_start_delalloc_roots
in flushoncommit"). After that change we started producing that warning,
and every now and then a user reports this since the warning happens too
often, it spams dmesg/syslog, and a user is unsure if this reflects any
problem that might compromise the filesystem's reliability.
We can not just lock the sb->s_umount semaphore before calling
writeback_inodes_sb(), because that would at least deadlock with
filesystem freezing, since at fs/super.c:freeze_super() sync_filesystem()
is called while we are holding that semaphore in write mode, and that can
trigger a transaction commit, resulting in a deadlock. It would also
trigger the same type of deadlock in the unmount path. Possibly, it could
also introduce some other locking dependencies that lockdep would report.
To fix this call try_to_writeback_inodes_sb() instead of
writeback_inodes_sb(), because that will try to read lock sb->s_umount
and then will only call writeback_inodes_sb() if it was able to lock it.
This is fine because the cases where it can't read lock sb->s_umount
are during a filesystem unmount or during a filesystem freeze - in those
cases sb->s_umount is write locked and sync_filesystem() is called, which
calls writeback_inodes_sb(). In other words, in all cases where we can't
take a read lock on sb->s_umount, writeback is already being triggered
elsewhere.
An alternative would be to call btrfs_start_delalloc_roots() with a
number of pages different from LONG_MAX, for example matching the number
of delalloc bytes we currently have, in
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-22
In the Linux kernel, the following vulnerability has been resolved:
ibmvnic: free reset-work-item when flushing
Fix a tiny memory leak when flushing the reset work queue.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-22
In the Linux kernel, the following vulnerability has been resolved:
mptcp: Correctly set DATA_FIN timeout when number of retransmits is large
Syzkaller with UBSAN uncovered a scenario where a large number of
DATA_FIN retransmits caused a shift-out-of-bounds in the DATA_FIN
timeout calculation:
================================================================================
UBSAN: shift-out-of-bounds in net/mptcp/protocol.c:470:29
shift exponent 32 is too large for 32-bit type 'unsigned int'
CPU: 1 PID: 13059 Comm: kworker/1:0 Not tainted 5.17.0-rc2-00630-g5fbf21c90c60 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Workqueue: events mptcp_worker
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
ubsan_epilogue+0xb/0x5a lib/ubsan.c:151
__ubsan_handle_shift_out_of_bounds.cold+0xb2/0x20e lib/ubsan.c:330
mptcp_set_datafin_timeout net/mptcp/protocol.c:470 [inline]
__mptcp_retrans.cold+0x72/0x77 net/mptcp/protocol.c:2445
mptcp_worker+0x58a/0xa70 net/mptcp/protocol.c:2528
process_one_work+0x9df/0x16d0 kernel/workqueue.c:2307
worker_thread+0x95/0xe10 kernel/workqueue.c:2454
kthread+0x2f4/0x3b0 kernel/kthread.c:377
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
================================================================================
This change limits the maximum timeout by limiting the size of the
shift, which keeps all intermediate values in-bounds.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-22
In the Linux kernel, the following vulnerability has been resolved:
auxdisplay: lcd2s: Fix memory leak in ->remove()
Once allocated the struct lcd2s_data is never freed.
Fix the memory leak by switching to devm_kzalloc().
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-22
In the Linux kernel, the following vulnerability has been resolved:
net: arcnet: com20020: Fix null-ptr-deref in com20020pci_probe()
During driver initialization, the pointer of card info, i.e. the
variable 'ci' is required. However, the definition of
'com20020pci_id_table' reveals that this field is empty for some
devices, which will cause null pointer dereference when initializing
these devices.
The following log reveals it:
[ 3.973806] KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
[ 3.973819] RIP: 0010:com20020pci_probe+0x18d/0x13e0 [com20020_pci]
[ 3.975181] Call Trace:
[ 3.976208] local_pci_probe+0x13f/0x210
[ 3.977248] pci_device_probe+0x34c/0x6d0
[ 3.977255] ? pci_uevent+0x470/0x470
[ 3.978265] really_probe+0x24c/0x8d0
[ 3.978273] __driver_probe_device+0x1b3/0x280
[ 3.979288] driver_probe_device+0x50/0x370
Fix this by checking whether the 'ci' is a null pointer first.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-22
In the Linux kernel, the following vulnerability has been resolved:
net/smc: fix connection leak
There's a potential leak issue under following execution sequence :
smc_release smc_connect_work
if (sk->sk_state == SMC_INIT)
send_clc_confirim
tcp_abort();
...
sk.sk_state = SMC_ACTIVE
smc_close_active
switch(sk->sk_state) {
...
case SMC_ACTIVE:
smc_close_final()
// then wait peer closed
Unfortunately, tcp_abort() may discard CLC CONFIRM messages that are
still in the tcp send buffer, in which case our connection token cannot
be delivered to the server side, which means that we cannot get a
passive close message at all. Therefore, it is impossible for the to be
disconnected at all.
This patch tries a very simple way to avoid this issue, once the state
has changed to SMC_ACTIVE after tcp_abort(), we can actively abort the
smc connection, considering that the state is SMC_INIT before
tcp_abort(), abandoning the complete disconnection process should not
cause too much problem.
In fact, this problem may exist as long as the CLC CONFIRM message is
not received by the server. Whether a timer should be added after
smc_close_final() needs to be discussed in the future. But even so, this
patch provides a faster release for connection in above case, it should
also be valuable.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-22
In the Linux kernel, the following vulnerability has been resolved:
net: ipv6: ensure we call ipv6_mc_down() at most once
There are two reasons for addrconf_notify() to be called with NETDEV_DOWN:
either the network device is actually going down, or IPv6 was disabled
on the interface.
If either of them stays down while the other is toggled, we repeatedly
call the code for NETDEV_DOWN, including ipv6_mc_down(), while never
calling the corresponding ipv6_mc_up() in between. This will cause a
new entry in idev->mc_tomb to be allocated for each multicast group
the interface is subscribed to, which in turn leaks one struct ifmcaddr6
per nontrivial multicast group the interface is subscribed to.
The following reproducer will leak at least $n objects:
ip addr add ff2e::4242/32 dev eth0 autojoin
sysctl -w net.ipv6.conf.eth0.disable_ipv6=1
for i in $(seq 1 $n); do
ip link set up eth0; ip link set down eth0
done
Joining groups with IPV6_ADD_MEMBERSHIP (unprivileged) or setting the
sysctl net.ipv6.conf.eth0.forwarding to 1 (=> subscribing to ff02::2)
can also be used to create a nontrivial idev->mc_list, which will the
leak objects with the right up-down-sequence.
Based on both sources for NETDEV_DOWN events the interface IPv6 state
should be considered:
- not ready if the network interface is not ready OR IPv6 is disabled
for it
- ready if the network interface is ready AND IPv6 is enabled for it
The functions ipv6_mc_up() and ipv6_down() should only be run when this
state changes.
Implement this by remembering when the IPv6 state is ready, and only
run ipv6_mc_down() if it actually changed from ready to not ready.
The other direction (not ready -> ready) already works correctly, as:
- the interface notification triggered codepath for NETDEV_UP /
NETDEV_CHANGE returns early if ipv6 is disabled, and
- the disable_ipv6=0 triggered codepath skips fully initializing the
interface as long as addrconf_link_ready(dev) returns false
- calling ipv6_mc_up() repeatedly does not leak anything
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-22
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_queue: fix possible use-after-free
Eric Dumazet says:
The sock_hold() side seems suspect, because there is no guarantee
that sk_refcnt is not already 0.
On failure, we cannot queue the packet and need to indicate an
error. The packet will be dropped by the caller.
v2: split skb prefetch hunk into separate change
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-22