Linux: >> Linux Kernel >> 3.0.94 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
serial: max310x: fix NULL pointer dereference in I2C instantiation
When trying to instantiate a max14830 device from userspace:
echo max14830 0x60 > /sys/bus/i2c/devices/i2c-2/new_device
we get the following error:
Unable to handle kernel NULL pointer dereference at virtual address...
...
Call trace:
max310x_i2c_probe+0x48/0x170 [max310x]
i2c_device_probe+0x150/0x2a0
...
Add check for validity of devtype to prevent the error, and abort probe
with a meaningful error message.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix OOB in nilfs_set_de_type
The size of the nilfs_type_by_mode array in the fs/nilfs2/dir.c file is
defined as "S_IFMT >> S_SHIFT", but the nilfs_set_de_type() function,
which uses this array, specifies the index to read from the array in the
same way as "(mode & S_IFMT) >> S_SHIFT".
static void nilfs_set_de_type(struct nilfs_dir_entry *de, struct inode
*inode)
{
umode_t mode = inode->i_mode;
de->file_type = nilfs_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; // oob
}
However, when the index is determined this way, an out-of-bounds (OOB)
error occurs by referring to an index that is 1 larger than the array size
when the condition "mode & S_IFMT == S_IFMT" is satisfied. Therefore, a
patch to resize the nilfs_type_by_mode array should be applied to prevent
OOB errors.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved:
Squashfs: check the inode number is not the invalid value of zero
Syskiller has produced an out of bounds access in fill_meta_index().
That out of bounds access is ultimately caused because the inode
has an inode number with the invalid value of zero, which was not checked.
The reason this causes the out of bounds access is due to following
sequence of events:
1. Fill_meta_index() is called to allocate (via empty_meta_index())
and fill a metadata index. It however suffers a data read error
and aborts, invalidating the newly returned empty metadata index.
It does this by setting the inode number of the index to zero,
which means unused (zero is not a valid inode number).
2. When fill_meta_index() is subsequently called again on another
read operation, locate_meta_index() returns the previous index
because it matches the inode number of 0. Because this index
has been returned it is expected to have been filled, and because
it hasn't been, an out of bounds access is performed.
This patch adds a sanity check which checks that the inode number
is not zero when the inode is created and returns -EINVAL if it is.
[phillip@squashfs.org.uk: whitespace fix]
CVSS Score
7.1
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved:
KVM: Always flush async #PF workqueue when vCPU is being destroyed
Always flush the per-vCPU async #PF workqueue when a vCPU is clearing its
completion queue, e.g. when a VM and all its vCPUs is being destroyed.
KVM must ensure that none of its workqueue callbacks is running when the
last reference to the KVM _module_ is put. Gifting a reference to the
associated VM prevents the workqueue callback from dereferencing freed
vCPU/VM memory, but does not prevent the KVM module from being unloaded
before the callback completes.
Drop the misguided VM refcount gifting, as calling kvm_put_kvm() from
async_pf_execute() if kvm_put_kvm() flushes the async #PF workqueue will
result in deadlock. async_pf_execute() can't return until kvm_put_kvm()
finishes, and kvm_put_kvm() can't return until async_pf_execute() finishes:
WARNING: CPU: 8 PID: 251 at virt/kvm/kvm_main.c:1435 kvm_put_kvm+0x2d/0x320 [kvm]
Modules linked in: vhost_net vhost vhost_iotlb tap kvm_intel kvm irqbypass
CPU: 8 PID: 251 Comm: kworker/8:1 Tainted: G W 6.6.0-rc1-e7af8d17224a-x86/gmem-vm #119
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Workqueue: events async_pf_execute [kvm]
RIP: 0010:kvm_put_kvm+0x2d/0x320 [kvm]
Call Trace:
<TASK>
async_pf_execute+0x198/0x260 [kvm]
process_one_work+0x145/0x2d0
worker_thread+0x27e/0x3a0
kthread+0xba/0xe0
ret_from_fork+0x2d/0x50
ret_from_fork_asm+0x11/0x20
</TASK>
---[ end trace 0000000000000000 ]---
INFO: task kworker/8:1:251 blocked for more than 120 seconds.
Tainted: G W 6.6.0-rc1-e7af8d17224a-x86/gmem-vm #119
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/8:1 state:D stack:0 pid:251 ppid:2 flags:0x00004000
Workqueue: events async_pf_execute [kvm]
Call Trace:
<TASK>
__schedule+0x33f/0xa40
schedule+0x53/0xc0
schedule_timeout+0x12a/0x140
__wait_for_common+0x8d/0x1d0
__flush_work.isra.0+0x19f/0x2c0
kvm_clear_async_pf_completion_queue+0x129/0x190 [kvm]
kvm_arch_destroy_vm+0x78/0x1b0 [kvm]
kvm_put_kvm+0x1c1/0x320 [kvm]
async_pf_execute+0x198/0x260 [kvm]
process_one_work+0x145/0x2d0
worker_thread+0x27e/0x3a0
kthread+0xba/0xe0
ret_from_fork+0x2d/0x50
ret_from_fork_asm+0x11/0x20
</TASK>
If kvm_clear_async_pf_completion_queue() actually flushes the workqueue,
then there's no need to gift async_pf_execute() a reference because all
invocations of async_pf_execute() will be forced to complete before the
vCPU and its VM are destroyed/freed. And that in turn fixes the module
unloading bug as __fput() won't do module_put() on the last vCPU reference
until the vCPU has been freed, e.g. if closing the vCPU file also puts the
last reference to the KVM module.
Note that kvm_check_async_pf_completion() may also take the work item off
the completion queue and so also needs to flush the work queue, as the
work will not be seen by kvm_clear_async_pf_completion_queue(). Waiting
on the workqueue could theoretically delay a vCPU due to waiting for the
work to complete, but that's a very, very small chance, and likely a very
small delay. kvm_arch_async_page_present_queued() unconditionally makes a
new request, i.e. will effectively delay entering the guest, so the
remaining work is really just:
trace_kvm_async_pf_completed(addr, cr2_or_gpa);
__kvm_vcpu_wake_up(vcpu);
mmput(mm);
and mmput() can't drop the last reference to the page tables if the vCPU is
still alive, i.e. the vCPU won't get stuck tearing down page tables.
Add a helper to do the flushing, specifically to deal with "wakeup all"
work items, as they aren't actually work items, i.e. are never placed in a
workqueue. Trying to flush a bogus workqueue entry rightly makes
__flush_work() complain (kudos to whoever added that sanity check).
Note, commit 5f6de5cbebee ("KVM: Prevent module exit until al
---truncated---
CVSS Score
7.0
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved:
nfs: fix UAF in direct writes
In production we have been hitting the following warning consistently
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 17 PID: 1800359 at lib/refcount.c:28 refcount_warn_saturate+0x9c/0xe0
Workqueue: nfsiod nfs_direct_write_schedule_work [nfs]
RIP: 0010:refcount_warn_saturate+0x9c/0xe0
PKRU: 55555554
Call Trace:
<TASK>
? __warn+0x9f/0x130
? refcount_warn_saturate+0x9c/0xe0
? report_bug+0xcc/0x150
? handle_bug+0x3d/0x70
? exc_invalid_op+0x16/0x40
? asm_exc_invalid_op+0x16/0x20
? refcount_warn_saturate+0x9c/0xe0
nfs_direct_write_schedule_work+0x237/0x250 [nfs]
process_one_work+0x12f/0x4a0
worker_thread+0x14e/0x3b0
? ZSTD_getCParams_internal+0x220/0x220
kthread+0xdc/0x120
? __btf_name_valid+0xa0/0xa0
ret_from_fork+0x1f/0x30
This is because we're completing the nfs_direct_request twice in a row.
The source of this is when we have our commit requests to submit, we
process them and send them off, and then in the completion path for the
commit requests we have
if (nfs_commit_end(cinfo.mds))
nfs_direct_write_complete(dreq);
However since we're submitting asynchronous requests we sometimes have
one that completes before we submit the next one, so we end up calling
complete on the nfs_direct_request twice.
The only other place we use nfs_generic_commit_list() is in
__nfs_commit_inode, which wraps this call in a
nfs_commit_begin();
nfs_commit_end();
Which is a common pattern for this style of completion handling, one
that is also repeated in the direct code with get_dreq()/put_dreq()
calls around where we process events as well as in the completion paths.
Fix this by using the same pattern for the commit requests.
Before with my 200 node rocksdb stress running this warning would pop
every 10ish minutes. With my patch the stress test has been running for
several hours without popping.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved:
dm-raid456, md/raid456: fix a deadlock for dm-raid456 while io concurrent with reshape
For raid456, if reshape is still in progress, then IO across reshape
position will wait for reshape to make progress. However, for dm-raid,
in following cases reshape will never make progress hence IO will hang:
1) the array is read-only;
2) MD_RECOVERY_WAIT is set;
3) MD_RECOVERY_FROZEN is set;
After commit c467e97f079f ("md/raid6: use valid sector values to determine
if an I/O should wait on the reshape") fix the problem that IO across
reshape position doesn't wait for reshape, the dm-raid test
shell/lvconvert-raid-reshape.sh start to hang:
[root@fedora ~]# cat /proc/979/stack
[<0>] wait_woken+0x7d/0x90
[<0>] raid5_make_request+0x929/0x1d70 [raid456]
[<0>] md_handle_request+0xc2/0x3b0 [md_mod]
[<0>] raid_map+0x2c/0x50 [dm_raid]
[<0>] __map_bio+0x251/0x380 [dm_mod]
[<0>] dm_submit_bio+0x1f0/0x760 [dm_mod]
[<0>] __submit_bio+0xc2/0x1c0
[<0>] submit_bio_noacct_nocheck+0x17f/0x450
[<0>] submit_bio_noacct+0x2bc/0x780
[<0>] submit_bio+0x70/0xc0
[<0>] mpage_readahead+0x169/0x1f0
[<0>] blkdev_readahead+0x18/0x30
[<0>] read_pages+0x7c/0x3b0
[<0>] page_cache_ra_unbounded+0x1ab/0x280
[<0>] force_page_cache_ra+0x9e/0x130
[<0>] page_cache_sync_ra+0x3b/0x110
[<0>] filemap_get_pages+0x143/0xa30
[<0>] filemap_read+0xdc/0x4b0
[<0>] blkdev_read_iter+0x75/0x200
[<0>] vfs_read+0x272/0x460
[<0>] ksys_read+0x7a/0x170
[<0>] __x64_sys_read+0x1c/0x30
[<0>] do_syscall_64+0xc6/0x230
[<0>] entry_SYSCALL_64_after_hwframe+0x6c/0x74
This is because reshape can't make progress.
For md/raid, the problem doesn't exist because register new sync_thread
doesn't rely on the IO to be done any more:
1) If array is read-only, it can switch to read-write by ioctl/sysfs;
2) md/raid never set MD_RECOVERY_WAIT;
3) If MD_RECOVERY_FROZEN is set, mddev_suspend() doesn't hold
'reconfig_mutex', hence it can be cleared and reshape can continue by
sysfs api 'sync_action'.
However, I'm not sure yet how to avoid the problem in dm-raid yet. This
patch on the one hand make sure raid_message() can't change
sync_thread() through raid_message() after presuspend(), on the other
hand detect the above 3 cases before wait for IO do be done in
dm_suspend(), and let dm-raid requeue those IO.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: prevent kernel bug at submit_bh_wbc()
Fix a bug where nilfs_get_block() returns a successful status when
searching and inserting the specified block both fail inconsistently. If
this inconsistent behavior is not due to a previously fixed bug, then an
unexpected race is occurring, so return a temporary error -EAGAIN instead.
This prevents callers such as __block_write_begin_int() from requesting a
read into a buffer that is not mapped, which would cause the BUG_ON check
for the BH_Mapped flag in submit_bh_wbc() to fail.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix failure to detect DAT corruption in btree and direct mappings
Patch series "nilfs2: fix kernel bug at submit_bh_wbc()".
This resolves a kernel BUG reported by syzbot. Since there are two
flaws involved, I've made each one a separate patch.
The first patch alone resolves the syzbot-reported bug, but I think
both fixes should be sent to stable, so I've tagged them as such.
This patch (of 2):
Syzbot has reported a kernel bug in submit_bh_wbc() when writing file data
to a nilfs2 file system whose metadata is corrupted.
There are two flaws involved in this issue.
The first flaw is that when nilfs_get_block() locates a data block using
btree or direct mapping, if the disk address translation routine
nilfs_dat_translate() fails with internal code -ENOENT due to DAT metadata
corruption, it can be passed back to nilfs_get_block(). This causes
nilfs_get_block() to misidentify an existing block as non-existent,
causing both data block lookup and insertion to fail inconsistently.
The second flaw is that nilfs_get_block() returns a successful status in
this inconsistent state. This causes the caller __block_write_begin_int()
or others to request a read even though the buffer is not mapped,
resulting in a BUG_ON check for the BH_Mapped flag in submit_bh_wbc()
failing.
This fixes the first issue by changing the return value to code -EINVAL
when a conversion using DAT fails with code -ENOENT, avoiding the
conflicting condition that leads to the kernel bug described above. Here,
code -EINVAL indicates that metadata corruption was detected during the
block lookup, which will be properly handled as a file system error and
converted to -EIO when passing through the nilfs2 bmap layer.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved:
s390/zcrypt: fix reference counting on zcrypt card objects
Tests with hot-plugging crytpo cards on KVM guests with debug
kernel build revealed an use after free for the load field of
the struct zcrypt_card. The reason was an incorrect reference
handling of the zcrypt card object which could lead to a free
of the zcrypt card object while it was still in use.
This is an example of the slab message:
kernel: 0x00000000885a7512-0x00000000885a7513 @offset=1298. First byte 0x68 instead of 0x6b
kernel: Allocated in zcrypt_card_alloc+0x36/0x70 [zcrypt] age=18046 cpu=3 pid=43
kernel: kmalloc_trace+0x3f2/0x470
kernel: zcrypt_card_alloc+0x36/0x70 [zcrypt]
kernel: zcrypt_cex4_card_probe+0x26/0x380 [zcrypt_cex4]
kernel: ap_device_probe+0x15c/0x290
kernel: really_probe+0xd2/0x468
kernel: driver_probe_device+0x40/0xf0
kernel: __device_attach_driver+0xc0/0x140
kernel: bus_for_each_drv+0x8c/0xd0
kernel: __device_attach+0x114/0x198
kernel: bus_probe_device+0xb4/0xc8
kernel: device_add+0x4d2/0x6e0
kernel: ap_scan_adapter+0x3d0/0x7c0
kernel: ap_scan_bus+0x5a/0x3b0
kernel: ap_scan_bus_wq_callback+0x40/0x60
kernel: process_one_work+0x26e/0x620
kernel: worker_thread+0x21c/0x440
kernel: Freed in zcrypt_card_put+0x54/0x80 [zcrypt] age=9024 cpu=3 pid=43
kernel: kfree+0x37e/0x418
kernel: zcrypt_card_put+0x54/0x80 [zcrypt]
kernel: ap_device_remove+0x4c/0xe0
kernel: device_release_driver_internal+0x1c4/0x270
kernel: bus_remove_device+0x100/0x188
kernel: device_del+0x164/0x3c0
kernel: device_unregister+0x30/0x90
kernel: ap_scan_adapter+0xc8/0x7c0
kernel: ap_scan_bus+0x5a/0x3b0
kernel: ap_scan_bus_wq_callback+0x40/0x60
kernel: process_one_work+0x26e/0x620
kernel: worker_thread+0x21c/0x440
kernel: kthread+0x150/0x168
kernel: __ret_from_fork+0x3c/0x58
kernel: ret_from_fork+0xa/0x30
kernel: Slab 0x00000372022169c0 objects=20 used=18 fp=0x00000000885a7c88 flags=0x3ffff00000000a00(workingset|slab|node=0|zone=1|lastcpupid=0x1ffff)
kernel: Object 0x00000000885a74b8 @offset=1208 fp=0x00000000885a7c88
kernel: Redzone 00000000885a74b0: bb bb bb bb bb bb bb bb ........
kernel: Object 00000000885a74b8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
kernel: Object 00000000885a74c8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
kernel: Object 00000000885a74d8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
kernel: Object 00000000885a74e8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
kernel: Object 00000000885a74f8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
kernel: Object 00000000885a7508: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 68 4b 6b 6b 6b a5 kkkkkkkkkkhKkkk.
kernel: Redzone 00000000885a7518: bb bb bb bb bb bb bb bb ........
kernel: Padding 00000000885a756c: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZ
kernel: CPU: 0 PID: 387 Comm: systemd-udevd Not tainted 6.8.0-HF #2
kernel: Hardware name: IBM 3931 A01 704 (KVM/Linux)
kernel: Call Trace:
kernel: [<00000000ca5ab5b8>] dump_stack_lvl+0x90/0x120
kernel: [<00000000c99d78bc>] check_bytes_and_report+0x114/0x140
kernel: [<00000000c99d53cc>] check_object+0x334/0x3f8
kernel: [<00000000c99d820c>] alloc_debug_processing+0xc4/0x1f8
kernel: [<00000000c99d852e>] get_partial_node.part.0+0x1ee/0x3e0
kernel: [<00000000c99d94ec>] ___slab_alloc+0xaf4/0x13c8
kernel: [<00000000c99d9e38>] __slab_alloc.constprop.0+0x78/0xb8
kernel: [<00000000c99dc8dc>] __kmalloc+0x434/0x590
kernel: [<00000000c9b4c0ce>] ext4_htree_store_dirent+0x4e/0x1c0
kernel: [<00000000c9b908a2>] htree_dirblock_to_tree+0x17a/0x3f0
kernel:
---truncated---
CVSS Score
7.8
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved:
crypto: iaa - Fix nr_cpus < nr_iaa case
If nr_cpus < nr_iaa, the calculated cpus_per_iaa will be 0, which
causes a divide-by-0 in rebalance_wq_table().
Make sure cpus_per_iaa is 1 in that case, and also in the nr_iaa == 0
case, even though cpus_per_iaa is never used if nr_iaa == 0, for
paranoia.
CVSS Score
8.4
EPSS Score
0.0
Published
2024-05-01