Linux: >> Linux Kernel >> 6.6.48 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
mm/migrate_device: don't add folio to be freed to LRU in migrate_device_finalize()
If migration succeeded, we called
folio_migrate_flags()->mem_cgroup_migrate() to migrate the memcg from the
old to the new folio. This will set memcg_data of the old folio to 0.
Similarly, if migration failed, memcg_data of the dst folio is left unset.
If we call folio_putback_lru() on such folios (memcg_data == 0), we will
add the folio to be freed to the LRU, making memcg code unhappy. Running
the hmm selftests:
# ./hmm-tests
...
# RUN hmm.hmm_device_private.migrate ...
[ 102.078007][T14893] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x7ff27d200 pfn:0x13cc00
[ 102.079974][T14893] anon flags: 0x17ff00000020018(uptodate|dirty|swapbacked|node=0|zone=2|lastcpupid=0x7ff)
[ 102.082037][T14893] raw: 017ff00000020018 dead000000000100 dead000000000122 ffff8881353896c9
[ 102.083687][T14893] raw: 00000007ff27d200 0000000000000000 00000001ffffffff 0000000000000000
[ 102.085331][T14893] page dumped because: VM_WARN_ON_ONCE_FOLIO(!memcg && !mem_cgroup_disabled())
[ 102.087230][T14893] ------------[ cut here ]------------
[ 102.088279][T14893] WARNING: CPU: 0 PID: 14893 at ./include/linux/memcontrol.h:726 folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.090478][T14893] Modules linked in:
[ 102.091244][T14893] CPU: 0 UID: 0 PID: 14893 Comm: hmm-tests Not tainted 6.13.0-09623-g6c216bc522fd #151
[ 102.093089][T14893] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014
[ 102.094848][T14893] RIP: 0010:folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.096104][T14893] Code: ...
[ 102.099908][T14893] RSP: 0018:ffffc900236c37b0 EFLAGS: 00010293
[ 102.101152][T14893] RAX: 0000000000000000 RBX: ffffea0004f30000 RCX: ffffffff8183f426
[ 102.102684][T14893] RDX: ffff8881063cb880 RSI: ffffffff81b8117f RDI: ffff8881063cb880
[ 102.104227][T14893] RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
[ 102.105757][T14893] R10: 0000000000000001 R11: 0000000000000002 R12: ffffc900236c37d8
[ 102.107296][T14893] R13: ffff888277a2bcb0 R14: 000000000000001f R15: 0000000000000000
[ 102.108830][T14893] FS: 00007ff27dbdd740(0000) GS:ffff888277a00000(0000) knlGS:0000000000000000
[ 102.110643][T14893] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 102.111924][T14893] CR2: 00007ff27d400000 CR3: 000000010866e000 CR4: 0000000000750ef0
[ 102.113478][T14893] PKRU: 55555554
[ 102.114172][T14893] Call Trace:
[ 102.114805][T14893] <TASK>
[ 102.115397][T14893] ? folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.116547][T14893] ? __warn.cold+0x110/0x210
[ 102.117461][T14893] ? folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.118667][T14893] ? report_bug+0x1b9/0x320
[ 102.119571][T14893] ? handle_bug+0x54/0x90
[ 102.120494][T14893] ? exc_invalid_op+0x17/0x50
[ 102.121433][T14893] ? asm_exc_invalid_op+0x1a/0x20
[ 102.122435][T14893] ? __wake_up_klogd.part.0+0x76/0xd0
[ 102.123506][T14893] ? dump_page+0x4f/0x60
[ 102.124352][T14893] ? folio_lruvec_lock_irqsave+0x10e/0x170
[ 102.125500][T14893] folio_batch_move_lru+0xd4/0x200
[ 102.126577][T14893] ? __pfx_lru_add+0x10/0x10
[ 102.127505][T14893] __folio_batch_add_and_move+0x391/0x720
[ 102.128633][T14893] ? __pfx_lru_add+0x10/0x10
[ 102.129550][T14893] folio_putback_lru+0x16/0x80
[ 102.130564][T14893] migrate_device_finalize+0x9b/0x530
[ 102.131640][T14893] dmirror_migrate_to_device.constprop.0+0x7c5/0xad0
[ 102.133047][T14893] dmirror_fops_unlocked_ioctl+0x89b/0xc80
Likely, nothing else goes wrong: putting the last folio reference will
remove the folio from the LRU again. So besides memcg complaining, adding
the folio to be freed to the LRU is just an unnecessary step.
The new flow resembles what we have in migrate_folio_move(): add the dst
to the lru, rem
---truncated---
CVSS Score
5.5
EPSS Score
0.001
Published
2025-03-12
In the Linux kernel, the following vulnerability has been resolved:
drop_monitor: fix incorrect initialization order
Syzkaller reports the following bug:
BUG: spinlock bad magic on CPU#1, syz-executor.0/7995
lock: 0xffff88805303f3e0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
CPU: 1 PID: 7995 Comm: syz-executor.0 Tainted: G E 5.10.209+ #1
Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x119/0x179 lib/dump_stack.c:118
debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]
do_raw_spin_lock+0x1f6/0x270 kernel/locking/spinlock_debug.c:112
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:117 [inline]
_raw_spin_lock_irqsave+0x50/0x70 kernel/locking/spinlock.c:159
reset_per_cpu_data+0xe6/0x240 [drop_monitor]
net_dm_cmd_trace+0x43d/0x17a0 [drop_monitor]
genl_family_rcv_msg_doit+0x22f/0x330 net/netlink/genetlink.c:739
genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]
genl_rcv_msg+0x341/0x5a0 net/netlink/genetlink.c:800
netlink_rcv_skb+0x14d/0x440 net/netlink/af_netlink.c:2497
genl_rcv+0x29/0x40 net/netlink/genetlink.c:811
netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]
netlink_unicast+0x54b/0x800 net/netlink/af_netlink.c:1348
netlink_sendmsg+0x914/0xe00 net/netlink/af_netlink.c:1916
sock_sendmsg_nosec net/socket.c:651 [inline]
__sock_sendmsg+0x157/0x190 net/socket.c:663
____sys_sendmsg+0x712/0x870 net/socket.c:2378
___sys_sendmsg+0xf8/0x170 net/socket.c:2432
__sys_sendmsg+0xea/0x1b0 net/socket.c:2461
do_syscall_64+0x30/0x40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x62/0xc7
RIP: 0033:0x7f3f9815aee9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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:00007f3f972bf0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f3f9826d050 RCX: 00007f3f9815aee9
RDX: 0000000020000000 RSI: 0000000020001300 RDI: 0000000000000007
RBP: 00007f3f981b63bd R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f3f9826d050 R15: 00007ffe01ee6768
If drop_monitor is built as a kernel module, syzkaller may have time
to send a netlink NET_DM_CMD_START message during the module loading.
This will call the net_dm_monitor_start() function that uses
a spinlock that has not yet been initialized.
To fix this, let's place resource initialization above the registration
of a generic netlink family.
Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with Syzkaller.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-03-12
In the Linux kernel, the following vulnerability has been resolved:
io_uring: prevent opcode speculation
sqe->opcode is used for different tables, make sure we santitise it
against speculations.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-03-12
In the Linux kernel, the following vulnerability has been resolved:
tcp: drop secpath at the same time as we currently drop dst
Xiumei reported hitting the WARN in xfrm6_tunnel_net_exit while
running tests that boil down to:
- create a pair of netns
- run a basic TCP test over ipcomp6
- delete the pair of netns
The xfrm_state found on spi_byaddr was not deleted at the time we
delete the netns, because we still have a reference on it. This
lingering reference comes from a secpath (which holds a ref on the
xfrm_state), which is still attached to an skb. This skb is not
leaked, it ends up on sk_receive_queue and then gets defer-free'd by
skb_attempt_defer_free.
The problem happens when we defer freeing an skb (push it on one CPU's
defer_list), and don't flush that list before the netns is deleted. In
that case, we still have a reference on the xfrm_state that we don't
expect at this point.
We already drop the skb's dst in the TCP receive path when it's no
longer needed, so let's also drop the secpath. At this point,
tcp_filter has already called into the LSM hooks that may require the
secpath, so it should not be needed anymore. However, in some of those
places, the MPTCP extension has just been attached to the skb, so we
cannot simply drop all extensions.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-03-12
In the Linux kernel, the following vulnerability has been resolved:
powerpc/code-patching: Fix KASAN hit by not flagging text patching area as VM_ALLOC
Erhard reported the following KASAN hit while booting his PowerMac G4
with a KASAN-enabled kernel 6.13-rc6:
BUG: KASAN: vmalloc-out-of-bounds in copy_to_kernel_nofault+0xd8/0x1c8
Write of size 8 at addr f1000000 by task chronyd/1293
CPU: 0 UID: 123 PID: 1293 Comm: chronyd Tainted: G W 6.13.0-rc6-PMacG4 #2
Tainted: [W]=WARN
Hardware name: PowerMac3,6 7455 0x80010303 PowerMac
Call Trace:
[c2437590] [c1631a84] dump_stack_lvl+0x70/0x8c (unreliable)
[c24375b0] [c0504998] print_report+0xdc/0x504
[c2437610] [c050475c] kasan_report+0xf8/0x108
[c2437690] [c0505a3c] kasan_check_range+0x24/0x18c
[c24376a0] [c03fb5e4] copy_to_kernel_nofault+0xd8/0x1c8
[c24376c0] [c004c014] patch_instructions+0x15c/0x16c
[c2437710] [c00731a8] bpf_arch_text_copy+0x60/0x7c
[c2437730] [c0281168] bpf_jit_binary_pack_finalize+0x50/0xac
[c2437750] [c0073cf4] bpf_int_jit_compile+0xb30/0xdec
[c2437880] [c0280394] bpf_prog_select_runtime+0x15c/0x478
[c24378d0] [c1263428] bpf_prepare_filter+0xbf8/0xc14
[c2437990] [c12677ec] bpf_prog_create_from_user+0x258/0x2b4
[c24379d0] [c027111c] do_seccomp+0x3dc/0x1890
[c2437ac0] [c001d8e0] system_call_exception+0x2dc/0x420
[c2437f30] [c00281ac] ret_from_syscall+0x0/0x2c
--- interrupt: c00 at 0x5a1274
NIP: 005a1274 LR: 006a3b3c CTR: 005296c8
REGS: c2437f40 TRAP: 0c00 Tainted: G W (6.13.0-rc6-PMacG4)
MSR: 0200f932 <VEC,EE,PR,FP,ME,IR,DR,RI> CR: 24004422 XER: 00000000
GPR00: 00000166 af8f3fa0 a7ee3540 00000001 00000000 013b6500 005a5858 0200f932
GPR08: 00000000 00001fe9 013d5fc8 005296c8 2822244c 00b2fcd8 00000000 af8f4b57
GPR16: 00000000 00000001 00000000 00000000 00000000 00000001 00000000 00000002
GPR24: 00afdbb0 00000000 00000000 00000000 006e0004 013ce060 006e7c1c 00000001
NIP [005a1274] 0x5a1274
LR [006a3b3c] 0x6a3b3c
--- interrupt: c00
The buggy address belongs to the virtual mapping at
[f1000000, f1002000) created by:
text_area_cpu_up+0x20/0x190
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:00000000 index:0x0 pfn:0x76e30
flags: 0x80000000(zone=2)
raw: 80000000 00000000 00000122 00000000 00000000 00000000 ffffffff 00000001
raw: 00000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
f0ffff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
f0ffff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>f1000000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
^
f1000080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
f1000100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
==================================================================
f8 corresponds to KASAN_VMALLOC_INVALID which means the area is not
initialised hence not supposed to be used yet.
Powerpc text patching infrastructure allocates a virtual memory area
using get_vm_area() and flags it as VM_ALLOC. But that flag is meant
to be used for vmalloc() and vmalloc() allocated memory is not
supposed to be used before a call to __vmalloc_node_range() which is
never called for that area.
That went undetected until commit e4137f08816b ("mm, kasan, kmsan:
instrument copy_from/to_kernel_nofault")
The area allocated by text_area_cpu_up() is not vmalloc memory, it is
mapped directly on demand when needed by map_kernel_page(). There is
no VM flag corresponding to such usage, so just pass no flag. That way
the area will be unpoisonned and usable immediately.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-03-12
In the Linux kernel, the following vulnerability has been resolved:
bpf: avoid holding freeze_mutex during mmap operation
We use map->freeze_mutex to prevent races between map_freeze() and
memory mapping BPF map contents with writable permissions. The way we
naively do this means we'll hold freeze_mutex for entire duration of all
the mm and VMA manipulations, which is completely unnecessary. This can
potentially also lead to deadlocks, as reported by syzbot in [0].
So, instead, hold freeze_mutex only during writeability checks, bump
(proactively) "write active" count for the map, unlock the mutex and
proceed with mmap logic. And only if something went wrong during mmap
logic, then undo that "write active" counter increment.
[0] https://lore.kernel.org/bpf/678dcbc9.050a0220.303755.0066.GAE@google.com/
CVSS Score
5.5
EPSS Score
0.001
Published
2025-03-12
In the Linux kernel, the following vulnerability has been resolved:
sockmap, vsock: For connectible sockets allow only connected
sockmap expects all vsocks to have a transport assigned, which is expressed
in vsock_proto::psock_update_sk_prot(). However, there is an edge case
where an unconnected (connectible) socket may lose its previously assigned
transport. This is handled with a NULL check in the vsock/BPF recv path.
Another design detail is that listening vsocks are not supposed to have any
transport assigned at all. Which implies they are not supported by the
sockmap. But this is complicated by the fact that a socket, before
switching to TCP_LISTEN, may have had some transport assigned during a
failed connect() attempt. Hence, we may end up with a listening vsock in a
sockmap, which blows up quickly:
KASAN: null-ptr-deref in range [0x0000000000000120-0x0000000000000127]
CPU: 7 UID: 0 PID: 56 Comm: kworker/7:0 Not tainted 6.14.0-rc1+
Workqueue: vsock-loopback vsock_loopback_work
RIP: 0010:vsock_read_skb+0x4b/0x90
Call Trace:
sk_psock_verdict_data_ready+0xa4/0x2e0
virtio_transport_recv_pkt+0x1ca8/0x2acc
vsock_loopback_work+0x27d/0x3f0
process_one_work+0x846/0x1420
worker_thread+0x5b3/0xf80
kthread+0x35a/0x700
ret_from_fork+0x2d/0x70
ret_from_fork_asm+0x1a/0x30
For connectible sockets, instead of relying solely on the state of
vsk->transport, tell sockmap to only allow those representing established
connections. This aligns with the behaviour for AF_INET and AF_UNIX.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-03-12
In the Linux kernel, the following vulnerability has been resolved:
ibmvnic: Don't reference skb after sending to VIOS
Previously, after successfully flushing the xmit buffer to VIOS,
the tx_bytes stat was incremented by the length of the skb.
It is invalid to access the skb memory after sending the buffer to
the VIOS because, at any point after sending, the VIOS can trigger
an interrupt to free this memory. A race between reading skb->len
and freeing the skb is possible (especially during LPM) and will
result in use-after-free:
==================================================================
BUG: KASAN: slab-use-after-free in ibmvnic_xmit+0x75c/0x1808 [ibmvnic]
Read of size 4 at addr c00000024eb48a70 by task hxecom/14495
<...>
Call Trace:
[c000000118f66cf0] [c0000000018cba6c] dump_stack_lvl+0x84/0xe8 (unreliable)
[c000000118f66d20] [c0000000006f0080] print_report+0x1a8/0x7f0
[c000000118f66df0] [c0000000006f08f0] kasan_report+0x128/0x1f8
[c000000118f66f00] [c0000000006f2868] __asan_load4+0xac/0xe0
[c000000118f66f20] [c0080000046eac84] ibmvnic_xmit+0x75c/0x1808 [ibmvnic]
[c000000118f67340] [c0000000014be168] dev_hard_start_xmit+0x150/0x358
<...>
Freed by task 0:
kasan_save_stack+0x34/0x68
kasan_save_track+0x2c/0x50
kasan_save_free_info+0x64/0x108
__kasan_mempool_poison_object+0x148/0x2d4
napi_skb_cache_put+0x5c/0x194
net_tx_action+0x154/0x5b8
handle_softirqs+0x20c/0x60c
do_softirq_own_stack+0x6c/0x88
<...>
The buggy address belongs to the object at c00000024eb48a00 which
belongs to the cache skbuff_head_cache of size 224
==================================================================
CVSS Score
7.8
EPSS Score
0.0
Published
2025-03-12
In the Linux kernel, the following vulnerability has been resolved:
s390/ism: add release function for struct device
According to device_release() in /drivers/base/core.c,
a device without a release function is a broken device
and must be fixed.
The current code directly frees the device after calling device_add()
without waiting for other kernel parts to release their references.
Thus, a reference could still be held to a struct device,
e.g., by sysfs, leading to potential use-after-free
issues if a proper release function is not set.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-03-12
In the Linux kernel, the following vulnerability has been resolved:
net/sched: cls_api: fix error handling causing NULL dereference
tcf_exts_miss_cookie_base_alloc() calls xa_alloc_cyclic() which can
return 1 if the allocation succeeded after wrapping. This was treated as
an error, with value 1 returned to caller tcf_exts_init_ex() which sets
exts->actions to NULL and returns 1 to caller fl_change().
fl_change() treats err == 1 as success, calling tcf_exts_validate_ex()
which calls tcf_action_init() with exts->actions as argument, where it
is dereferenced.
Example trace:
BUG: kernel NULL pointer dereference, address: 0000000000000000
CPU: 114 PID: 16151 Comm: handler114 Kdump: loaded Not tainted 5.14.0-503.16.1.el9_5.x86_64 #1
RIP: 0010:tcf_action_init+0x1f8/0x2c0
Call Trace:
tcf_action_init+0x1f8/0x2c0
tcf_exts_validate_ex+0x175/0x190
fl_change+0x537/0x1120 [cls_flower]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-03-12