Security Vulnerabilities
- CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
mptcp: prevent BPF accessing lowat from a subflow socket.
Alexei reported the following splat:
WARNING: CPU: 32 PID: 3276 at net/mptcp/subflow.c:1430 subflow_data_ready+0x147/0x1c0
Modules linked in: dummy bpf_testmod(O) [last unloaded: bpf_test_no_cfi(O)]
CPU: 32 PID: 3276 Comm: test_progs Tainted: GO 6.8.0-12873-g2c43c33bfd23
Call Trace:
<TASK>
mptcp_set_rcvlowat+0x79/0x1d0
sk_setsockopt+0x6c0/0x1540
__bpf_setsockopt+0x6f/0x90
bpf_sock_ops_setsockopt+0x3c/0x90
bpf_prog_509ce5db2c7f9981_bpf_test_sockopt_int+0xb4/0x11b
bpf_prog_dce07e362d941d2b_bpf_test_socket_sockopt+0x12b/0x132
bpf_prog_348c9b5faaf10092_skops_sockopt+0x954/0xe86
__cgroup_bpf_run_filter_sock_ops+0xbc/0x250
tcp_connect+0x879/0x1160
tcp_v6_connect+0x50c/0x870
mptcp_connect+0x129/0x280
__inet_stream_connect+0xce/0x370
inet_stream_connect+0x36/0x50
bpf_trampoline_6442491565+0x49/0xef
inet_stream_connect+0x5/0x50
__sys_connect+0x63/0x90
__x64_sys_connect+0x14/0x20
The root cause of the issue is that bpf allows accessing mptcp-level
proto_ops from a tcp subflow scope.
Fix the issue detecting the problematic call and preventing any action.
In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: Prevent lock inversion deadlock in map delete elem
syzkaller started using corpuses where a BPF tracing program deletes
elements from a sockmap/sockhash map. Because BPF tracing programs can be
invoked from any interrupt context, locks taken during a map_delete_elem
operation must be hardirq-safe. Otherwise a deadlock due to lock inversion
is possible, as reported by lockdep:
CPU0 CPU1
---- ----
lock(&htab->buckets[i].lock);
local_irq_disable();
lock(&host->lock);
lock(&htab->buckets[i].lock);
<Interrupt>
lock(&host->lock);
Locks in sockmap are hardirq-unsafe by design. We expects elements to be
deleted from sockmap/sockhash only in task (normal) context with interrupts
enabled, or in softirq context.
Detect when map_delete_elem operation is invoked from a context which is
_not_ hardirq-unsafe, that is interrupts are disabled, and bail out with an
error.
Note that map updates are not affected by this issue. BPF verifier does not
allow updating sockmap/sockhash from a BPF tracing program today.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: validate user input for expected length
I got multiple syzbot reports showing old bugs exposed
by BPF after commit 20f2505fb436 ("bpf: Try to avoid kzalloc
in cgroup/{s,g}etsockopt")
setsockopt() @optlen argument should be taken into account
before copying data.
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr include/linux/sockptr.h:55 [inline]
BUG: KASAN: slab-out-of-bounds in do_replace net/ipv4/netfilter/ip_tables.c:1111 [inline]
BUG: KASAN: slab-out-of-bounds in do_ipt_set_ctl+0x902/0x3dd0 net/ipv4/netfilter/ip_tables.c:1627
Read of size 96 at addr ffff88802cd73da0 by task syz-executor.4/7238
CPU: 1 PID: 7238 Comm: syz-executor.4 Not tainted 6.9.0-rc2-next-20240403-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
__asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
copy_from_sockptr include/linux/sockptr.h:55 [inline]
do_replace net/ipv4/netfilter/ip_tables.c:1111 [inline]
do_ipt_set_ctl+0x902/0x3dd0 net/ipv4/netfilter/ip_tables.c:1627
nf_setsockopt+0x295/0x2c0 net/netfilter/nf_sockopt.c:101
do_sock_setsockopt+0x3af/0x720 net/socket.c:2311
__sys_setsockopt+0x1ae/0x250 net/socket.c:2334
__do_sys_setsockopt net/socket.c:2343 [inline]
__se_sys_setsockopt net/socket.c:2340 [inline]
__x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x72/0x7a
RIP: 0033:0x7fd22067dde9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd21f9ff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fd2207abf80 RCX: 00007fd22067dde9
RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fd2206ca47a R08: 0000000000000001 R09: 0000000000000000
R10: 0000000020000880 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd2207abf80 R15: 00007ffd2d0170d8
</TASK>
Allocated by task 7238:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slub.c:4069 [inline]
__kmalloc_noprof+0x200/0x410 mm/slub.c:4082
kmalloc_noprof include/linux/slab.h:664 [inline]
__cgroup_bpf_run_filter_setsockopt+0xd47/0x1050 kernel/bpf/cgroup.c:1869
do_sock_setsockopt+0x6b4/0x720 net/socket.c:2293
__sys_setsockopt+0x1ae/0x250 net/socket.c:2334
__do_sys_setsockopt net/socket.c:2343 [inline]
__se_sys_setsockopt net/socket.c:2340 [inline]
__x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x72/0x7a
The buggy address belongs to the object at ffff88802cd73da0
which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes inside of
allocated 1-byte region [ffff88802cd73da0, ffff88802cd73da1)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802cd73020 pfn:0x2cd73
flags: 0xfff80000000000(node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffefff(slab)
raw: 00fff80000000000 ffff888015041280 dead000000000100 dead000000000122
raw: ffff88802cd73020 000000008080007f 00000001ffffefff 00
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: discard table flag update with pending basechain deletion
Hook unregistration is deferred to the commit phase, same occurs with
hook updates triggered by the table dormant flag. When both commands are
combined, this results in deleting a basechain while leaving its hook
still registered in the core.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get()
nft_unregister_flowtable_type() within nf_flow_inet_module_exit() can
concurrent with __nft_flowtable_type_get() within nf_tables_newflowtable().
And thhere is not any protection when iterate over nf_tables_flowtables
list in __nft_flowtable_type_get(). Therefore, there is pertential
data-race of nf_tables_flowtables list entry.
Use list_for_each_entry_rcu() to iterate over nf_tables_flowtables list
in __nft_flowtable_type_get(), and use rcu_read_lock() in the caller
nft_flowtable_type_get() to protect the entire type query process.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: flush pending destroy work before exit_net release
Similar to 2c9f0293280e ("netfilter: nf_tables: flush pending destroy
work before netlink notifier") to address a race between exit_net and
the destroy workqueue.
The trace below shows an element to be released via destroy workqueue
while exit_net path (triggered via module removal) has already released
the set that is used in such transaction.
[ 1360.547789] BUG: KASAN: slab-use-after-free in nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.547861] Read of size 8 at addr ffff888140500cc0 by task kworker/4:1/152465
[ 1360.547870] CPU: 4 PID: 152465 Comm: kworker/4:1 Not tainted 6.8.0+ #359
[ 1360.547882] Workqueue: events nf_tables_trans_destroy_work [nf_tables]
[ 1360.547984] Call Trace:
[ 1360.547991] <TASK>
[ 1360.547998] dump_stack_lvl+0x53/0x70
[ 1360.548014] print_report+0xc4/0x610
[ 1360.548026] ? __virt_addr_valid+0xba/0x160
[ 1360.548040] ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[ 1360.548054] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.548176] kasan_report+0xae/0xe0
[ 1360.548189] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.548312] nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.548447] ? __pfx_nf_tables_trans_destroy_work+0x10/0x10 [nf_tables]
[ 1360.548577] ? _raw_spin_unlock_irq+0x18/0x30
[ 1360.548591] process_one_work+0x2f1/0x670
[ 1360.548610] worker_thread+0x4d3/0x760
[ 1360.548627] ? __pfx_worker_thread+0x10/0x10
[ 1360.548640] kthread+0x16b/0x1b0
[ 1360.548653] ? __pfx_kthread+0x10/0x10
[ 1360.548665] ret_from_fork+0x2f/0x50
[ 1360.548679] ? __pfx_kthread+0x10/0x10
[ 1360.548690] ret_from_fork_asm+0x1a/0x30
[ 1360.548707] </TASK>
[ 1360.548719] Allocated by task 192061:
[ 1360.548726] kasan_save_stack+0x20/0x40
[ 1360.548739] kasan_save_track+0x14/0x30
[ 1360.548750] __kasan_kmalloc+0x8f/0xa0
[ 1360.548760] __kmalloc_node+0x1f1/0x450
[ 1360.548771] nf_tables_newset+0x10c7/0x1b50 [nf_tables]
[ 1360.548883] nfnetlink_rcv_batch+0xbc4/0xdc0 [nfnetlink]
[ 1360.548909] nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink]
[ 1360.548927] netlink_unicast+0x367/0x4f0
[ 1360.548935] netlink_sendmsg+0x34b/0x610
[ 1360.548944] ____sys_sendmsg+0x4d4/0x510
[ 1360.548953] ___sys_sendmsg+0xc9/0x120
[ 1360.548961] __sys_sendmsg+0xbe/0x140
[ 1360.548971] do_syscall_64+0x55/0x120
[ 1360.548982] entry_SYSCALL_64_after_hwframe+0x55/0x5d
[ 1360.548994] Freed by task 192222:
[ 1360.548999] kasan_save_stack+0x20/0x40
[ 1360.549009] kasan_save_track+0x14/0x30
[ 1360.549019] kasan_save_free_info+0x3b/0x60
[ 1360.549028] poison_slab_object+0x100/0x180
[ 1360.549036] __kasan_slab_free+0x14/0x30
[ 1360.549042] kfree+0xb6/0x260
[ 1360.549049] __nft_release_table+0x473/0x6a0 [nf_tables]
[ 1360.549131] nf_tables_exit_net+0x170/0x240 [nf_tables]
[ 1360.549221] ops_exit_list+0x50/0xa0
[ 1360.549229] free_exit_list+0x101/0x140
[ 1360.549236] unregister_pernet_operations+0x107/0x160
[ 1360.549245] unregister_pernet_subsys+0x1c/0x30
[ 1360.549254] nf_tables_module_exit+0x43/0x80 [nf_tables]
[ 1360.549345] __do_sys_delete_module+0x253/0x370
[ 1360.549352] do_syscall_64+0x55/0x120
[ 1360.549360] entry_SYSCALL_64_after_hwframe+0x55/0x5d
(gdb) list *__nft_release_table+0x473
0x1e033 is in __nft_release_table (net/netfilter/nf_tables_api.c:11354).
11349 list_for_each_entry_safe(flowtable, nf, &table->flowtables, list) {
11350 list_del(&flowtable->list);
11351 nft_use_dec(&table->use);
11352 nf_tables_flowtable_destroy(flowtable);
11353 }
11354 list_for_each_entry_safe(set, ns, &table->sets, list) {
11355 list_del(&set->list);
11356 nft_use_dec(&table->use);
11357 if (set->flags & (NFT_SET_MAP | NFT_SET_OBJECT))
11358 nft_map_deactivat
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: reject new basechain after table flag update
When dormant flag is toggled, hooks are disabled in the commit phase by
iterating over current chains in table (existing and new).
The following configuration allows for an inconsistent state:
add table x
add chain x y { type filter hook input priority 0; }
add table x { flags dormant; }
add chain x w { type filter hook input priority 1; }
which triggers the following warning when trying to unregister chain w
which is already unregistered.
[ 127.322252] WARNING: CPU: 7 PID: 1211 at net/netfilter/core.c:50 1 __nf_unregister_net_hook+0x21a/0x260
[...]
[ 127.322519] Call Trace:
[ 127.322521] <TASK>
[ 127.322524] ? __warn+0x9f/0x1a0
[ 127.322531] ? __nf_unregister_net_hook+0x21a/0x260
[ 127.322537] ? report_bug+0x1b1/0x1e0
[ 127.322545] ? handle_bug+0x3c/0x70
[ 127.322552] ? exc_invalid_op+0x17/0x40
[ 127.322556] ? asm_exc_invalid_op+0x1a/0x20
[ 127.322563] ? kasan_save_free_info+0x3b/0x60
[ 127.322570] ? __nf_unregister_net_hook+0x6a/0x260
[ 127.322577] ? __nf_unregister_net_hook+0x21a/0x260
[ 127.322583] ? __nf_unregister_net_hook+0x6a/0x260
[ 127.322590] ? __nf_tables_unregister_hook+0x8a/0xe0 [nf_tables]
[ 127.322655] nft_table_disable+0x75/0xf0 [nf_tables]
[ 127.322717] nf_tables_commit+0x2571/0x2620 [nf_tables]
In the Linux kernel, the following vulnerability has been resolved:
net: mana: Fix Rx DMA datasize and skb_over_panic
mana_get_rxbuf_cfg() aligns the RX buffer's DMA datasize to be
multiple of 64. So a packet slightly bigger than mtu+14, say 1536,
can be received and cause skb_over_panic.
Sample dmesg:
[ 5325.237162] skbuff: skb_over_panic: text:ffffffffc043277a len:1536 put:1536 head:ff1100018b517000 data:ff1100018b517100 tail:0x700 end:0x6ea dev:<NULL>
[ 5325.243689] ------------[ cut here ]------------
[ 5325.245748] kernel BUG at net/core/skbuff.c:192!
[ 5325.247838] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[ 5325.258374] RIP: 0010:skb_panic+0x4f/0x60
[ 5325.302941] Call Trace:
[ 5325.304389] <IRQ>
[ 5325.315794] ? skb_panic+0x4f/0x60
[ 5325.317457] ? asm_exc_invalid_op+0x1f/0x30
[ 5325.319490] ? skb_panic+0x4f/0x60
[ 5325.321161] skb_put+0x4e/0x50
[ 5325.322670] mana_poll+0x6fa/0xb50 [mana]
[ 5325.324578] __napi_poll+0x33/0x1e0
[ 5325.326328] net_rx_action+0x12e/0x280
As discussed internally, this alignment is not necessary. To fix
this bug, remove it from the code. So oversized packets will be
marked as CQE_RX_TRUNCATED by NIC, and dropped.
In the Linux kernel, the following vulnerability has been resolved:
of: module: prevent NULL pointer dereference in vsnprintf()
In of_modalias(), we can get passed the str and len parameters which would
cause a kernel oops in vsnprintf() since it only allows passing a NULL ptr
when the length is also 0. Also, we need to filter out the negative values
of the len parameter as these will result in a really huge buffer since
snprintf() takes size_t parameter while ours is ssize_t...
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
In the Linux kernel, the following vulnerability has been resolved:
of: dynamic: Synchronize of_changeset_destroy() with the devlink removals
In the following sequence:
1) of_platform_depopulate()
2) of_overlay_remove()
During the step 1, devices are destroyed and devlinks are removed.
During the step 2, OF nodes are destroyed but
__of_changeset_entry_destroy() can raise warnings related to missing
of_node_put():
ERROR: memory leak, expected refcount 1 instead of 2 ...
Indeed, during the devlink removals performed at step 1, the removal
itself releasing the device (and the attached of_node) is done by a job
queued in a workqueue and so, it is done asynchronously with respect to
function calls.
When the warning is present, of_node_put() will be called but wrongly
too late from the workqueue job.
In order to be sure that any ongoing devlink removals are done before
the of_node destruction, synchronize the of_changeset_destroy() with the
devlink removals.