Security Vulnerabilities
- CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
NFS: Fix a potential NULL dereference in nfs_get_client()
None of the callers are expecting NULL returns from nfs_get_client() so
this code will lead to an Oops. It's better to return an error
pointer. I expect that this is dead code so hopefully no one is
affected.
In the Linux kernel, the following vulnerability has been resolved:
IB/mlx5: Fix initializing CQ fragments buffer
The function init_cq_frag_buf() can be called to initialize the current CQ
fragments buffer cq->buf, or the temporary cq->resize_buf that is filled
during CQ resize operation.
However, the offending commit started to use function get_cqe() for
getting the CQEs, the issue with this change is that get_cqe() always
returns CQEs from cq->buf, which leads us to initialize the wrong buffer,
and in case of enlarging the CQ we try to access elements beyond the size
of the current cq->buf and eventually hit a kernel panic.
[exception RIP: init_cq_frag_buf+103]
[ffff9f799ddcbcd8] mlx5_ib_resize_cq at ffffffffc0835d60 [mlx5_ib]
[ffff9f799ddcbdb0] ib_resize_cq at ffffffffc05270df [ib_core]
[ffff9f799ddcbdc0] llt_rdma_setup_qp at ffffffffc0a6a712 [llt]
[ffff9f799ddcbe10] llt_rdma_cc_event_action at ffffffffc0a6b411 [llt]
[ffff9f799ddcbe98] llt_rdma_client_conn_thread at ffffffffc0a6bb75 [llt]
[ffff9f799ddcbec8] kthread at ffffffffa66c5da1
[ffff9f799ddcbf50] ret_from_fork_nospec_begin at ffffffffa6d95ddd
Fix it by getting the needed CQE by calling mlx5_frag_buf_get_wqe() that
takes the correct source buffer as a parameter.
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Ensure liveliness of nested VM-Enter fail tracepoint message
Use the __string() machinery provided by the tracing subystem to make a
copy of the string literals consumed by the "nested VM-Enter failed"
tracepoint. A complete copy is necessary to ensure that the tracepoint
can't outlive the data/memory it consumes and deference stale memory.
Because the tracepoint itself is defined by kvm, if kvm-intel and/or
kvm-amd are built as modules, the memory holding the string literals
defined by the vendor modules will be freed when the module is unloaded,
whereas the tracepoint and its data in the ring buffer will live until
kvm is unloaded (or "indefinitely" if kvm is built-in).
This bug has existed since the tracepoint was added, but was recently
exposed by a new check in tracing to detect exactly this type of bug.
fmt: '%s%s
' current_buffer: ' vmx_dirty_log_t-140127 [003] .... kvm_nested_vmenter_failed: '
WARNING: CPU: 3 PID: 140134 at kernel/trace/trace.c:3759 trace_check_vprintf+0x3be/0x3e0
CPU: 3 PID: 140134 Comm: less Not tainted 5.13.0-rc1-ce2e73ce600a-req #184
Hardware name: ASUS Q87M-E/Q87M-E, BIOS 1102 03/03/2014
RIP: 0010:trace_check_vprintf+0x3be/0x3e0
Code: <0f> 0b 44 8b 4c 24 1c e9 a9 fe ff ff c6 44 02 ff 00 49 8b 97 b0 20
RSP: 0018:ffffa895cc37bcb0 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffa895cc37bd08 RCX: 0000000000000027
RDX: 0000000000000027 RSI: 00000000ffffdfff RDI: ffff9766cfad74f8
RBP: ffffffffc0a041d4 R08: ffff9766cfad74f0 R09: ffffa895cc37bad8
R10: 0000000000000001 R11: 0000000000000001 R12: ffffffffc0a041d4
R13: ffffffffc0f4dba8 R14: 0000000000000000 R15: ffff976409f2c000
FS: 00007f92fa200740(0000) GS:ffff9766cfac0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559bd11b0000 CR3: 000000019fbaa002 CR4: 00000000001726e0
Call Trace:
trace_event_printf+0x5e/0x80
trace_raw_output_kvm_nested_vmenter_failed+0x3a/0x60 [kvm]
print_trace_line+0x1dd/0x4e0
s_show+0x45/0x150
seq_read_iter+0x2d5/0x4c0
seq_read+0x106/0x150
vfs_read+0x98/0x180
ksys_read+0x5f/0xe0
do_syscall_64+0x40/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xae
In the Linux kernel, the following vulnerability has been resolved:
net: ipv4: fix memory leak in ip_mc_add1_src
BUG: memory leak
unreferenced object 0xffff888101bc4c00 (size 32):
comm "syz-executor527", pid 360, jiffies 4294807421 (age 19.329s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
01 00 00 00 00 00 00 00 ac 14 14 bb 00 00 02 00 ................
backtrace:
[<00000000f17c5244>] kmalloc include/linux/slab.h:558 [inline]
[<00000000f17c5244>] kzalloc include/linux/slab.h:688 [inline]
[<00000000f17c5244>] ip_mc_add1_src net/ipv4/igmp.c:1971 [inline]
[<00000000f17c5244>] ip_mc_add_src+0x95f/0xdb0 net/ipv4/igmp.c:2095
[<000000001cb99709>] ip_mc_source+0x84c/0xea0 net/ipv4/igmp.c:2416
[<0000000052cf19ed>] do_ip_setsockopt net/ipv4/ip_sockglue.c:1294 [inline]
[<0000000052cf19ed>] ip_setsockopt+0x114b/0x30c0 net/ipv4/ip_sockglue.c:1423
[<00000000477edfbc>] raw_setsockopt+0x13d/0x170 net/ipv4/raw.c:857
[<00000000e75ca9bb>] __sys_setsockopt+0x158/0x270 net/socket.c:2117
[<00000000bdb993a8>] __do_sys_setsockopt net/socket.c:2128 [inline]
[<00000000bdb993a8>] __se_sys_setsockopt net/socket.c:2125 [inline]
[<00000000bdb993a8>] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2125
[<000000006a1ffdbd>] do_syscall_64+0x40/0x80 arch/x86/entry/common.c:47
[<00000000b11467c4>] entry_SYSCALL_64_after_hwframe+0x44/0xae
In commit 24803f38a5c0 ("igmp: do not remove igmp souce list info when set
link down"), the ip_mc_clear_src() in ip_mc_destroy_dev() was removed,
because it was also called in igmpv3_clear_delrec().
Rough callgraph:
inetdev_destroy
-> ip_mc_destroy_dev
-> igmpv3_clear_delrec
-> ip_mc_clear_src
-> RCU_INIT_POINTER(dev->ip_ptr, NULL)
However, ip_mc_clear_src() called in igmpv3_clear_delrec() doesn't
release in_dev->mc_list->sources. And RCU_INIT_POINTER() assigns the
NULL to dev->ip_ptr. As a result, in_dev cannot be obtained through
inetdev_by_index() and then in_dev->mc_list->sources cannot be released
by ip_mc_del1_src() in the sock_close. Rough call sequence goes like:
sock_close
-> __sock_release
-> inet_release
-> ip_mc_drop_socket
-> inetdev_by_index
-> ip_mc_leave_src
-> ip_mc_del_src
-> ip_mc_del1_src
So we still need to call ip_mc_clear_src() in ip_mc_destroy_dev() to free
in_dev->mc_list->sources.
In the Linux kernel, the following vulnerability has been resolved:
net: usb: fix possible use-after-free in smsc75xx_bind
The commit 46a8b29c6306 ("net: usb: fix memory leak in smsc75xx_bind")
fails to clean up the work scheduled in smsc75xx_reset->
smsc75xx_set_multicast, which leads to use-after-free if the work is
scheduled to start after the deallocation. In addition, this patch
also removes a dangling pointer - dev->data[0].
This patch calls cancel_work_sync to cancel the scheduled work and set
the dangling pointer to NULL.
In the Linux kernel, the following vulnerability has been resolved:
net: qrtr: fix OOB Read in qrtr_endpoint_post
Syzbot reported slab-out-of-bounds Read in
qrtr_endpoint_post. The problem was in wrong
_size_ type:
if (len != ALIGN(size, 4) + hdrlen)
goto err;
If size from qrtr_hdr is 4294967293 (0xfffffffd), the result of
ALIGN(size, 4) will be 0. In case of len == hdrlen and size == 4294967293
in header this check won't fail and
skb_put_data(skb, data + hdrlen, size);
will read out of bound from data, which is hdrlen allocated block.
In the Linux kernel, the following vulnerability has been resolved:
ethtool: strset: fix message length calculation
Outer nest for ETHTOOL_A_STRSET_STRINGSETS is not accounted for.
This may result in ETHTOOL_MSG_STRSET_GET producing a warning like:
calculated message payload length (684) not sufficient
WARNING: CPU: 0 PID: 30967 at net/ethtool/netlink.c:369 ethnl_default_doit+0x87a/0xa20
and a splat.
As usually with such warnings three conditions must be met for the warning
to trigger:
- there must be no skb size rounding up (e.g. reply_size of 684);
- string set must be per-device (so that the header gets populated);
- the device name must be at least 12 characters long.
all in all with current user space it looks like reading priv flags
is the only place this could potentially happen. Or with syzbot :)
In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix soft lookup in subflow_error_report()
Maxim reported a soft lookup in subflow_error_report():
watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:0]
RIP: 0010:native_queued_spin_lock_slowpath
RSP: 0018:ffffa859c0003bc0 EFLAGS: 00000202
RAX: 0000000000000101 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff9195c2772d88 RSI: 0000000000000000 RDI: ffff9195c2772d88
RBP: ffff9195c2772d00 R08: 00000000000067b0 R09: c6e31da9eb1e44f4
R10: ffff9195ef379700 R11: ffff9195edb50710 R12: ffff9195c2772d88
R13: ffff9195f500e3d0 R14: ffff9195ef379700 R15: ffff9195ef379700
FS: 0000000000000000(0000) GS:ffff91961f400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c000407000 CR3: 0000000002988000 CR4: 00000000000006f0
Call Trace:
<IRQ>
_raw_spin_lock_bh
subflow_error_report
mptcp_subflow_data_available
__mptcp_move_skbs_from_subflow
mptcp_data_ready
tcp_data_queue
tcp_rcv_established
tcp_v4_do_rcv
tcp_v4_rcv
ip_protocol_deliver_rcu
ip_local_deliver_finish
__netif_receive_skb_one_core
netif_receive_skb
rtl8139_poll 8139too
__napi_poll
net_rx_action
__do_softirq
__irq_exit_rcu
common_interrupt
</IRQ>
The calling function - mptcp_subflow_data_available() - can be invoked
from different contexts:
- plain ssk socket lock
- ssk socket lock + mptcp_data_lock
- ssk socket lock + mptcp_data_lock + msk socket lock.
Since subflow_error_report() tries to acquire the mptcp_data_lock, the
latter two call chains will cause soft lookup.
This change addresses the issue moving the error reporting call to
outer functions, where the held locks list is known and the we can
acquire only the needed one.
In the Linux kernel, the following vulnerability has been resolved:
sch_cake: Fix out of bounds when parsing TCP options and header
The TCP option parser in cake qdisc (cake_get_tcpopt and
cake_tcph_may_drop) could read one byte out of bounds. When the length
is 1, the execution flow gets into the loop, reads one byte of the
opcode, and if the opcode is neither TCPOPT_EOL nor TCPOPT_NOP, it reads
one more byte, which exceeds the length of 1.
This fix is inspired by commit 9609dad263f8 ("ipv4: tcp_input: fix stack
out of bounds when parsing TCP options.").
v2 changes:
Added doff validation in cake_get_tcphdr to avoid parsing garbage as TCP
header. Although it wasn't strictly an out-of-bounds access (memory was
allocated), garbage values could be read where CAKE expected the TCP
header if doff was smaller than 5.
In the Linux kernel, the following vulnerability has been resolved:
mptcp: Fix out of bounds when parsing TCP options
The TCP option parser in mptcp (mptcp_get_options) could read one byte
out of bounds. When the length is 1, the execution flow gets into the
loop, reads one byte of the opcode, and if the opcode is neither
TCPOPT_EOL nor TCPOPT_NOP, it reads one more byte, which exceeds the
length of 1.
This fix is inspired by commit 9609dad263f8 ("ipv4: tcp_input: fix stack
out of bounds when parsing TCP options.").