Linux: >> Linux Kernel >> 2.6.31.4 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: mesh: Fix leak of mesh_preq_queue objects
The hwmp code use objects of type mesh_preq_queue, added to a list in
ieee80211_if_mesh, to keep track of mpath we need to resolve. If the mpath
gets deleted, ex mesh interface is removed, the entries in that list will
never get cleaned. Fix this by flushing all corresponding items of the
preq_queue in mesh_path_flush_pending().
This should take care of KASAN reports like this:
unreferenced object 0xffff00000668d800 (size 128):
comm "kworker/u8:4", pid 67, jiffies 4295419552 (age 1836.444s)
hex dump (first 32 bytes):
00 1f 05 09 00 00 ff ff 00 d5 68 06 00 00 ff ff ..........h.....
8e 97 ea eb 3e b8 01 00 00 00 00 00 00 00 00 00 ....>...........
backtrace:
[<000000007302a0b6>] __kmem_cache_alloc_node+0x1e0/0x35c
[<00000000049bd418>] kmalloc_trace+0x34/0x80
[<0000000000d792bb>] mesh_queue_preq+0x44/0x2a8
[<00000000c99c3696>] mesh_nexthop_resolve+0x198/0x19c
[<00000000926bf598>] ieee80211_xmit+0x1d0/0x1f4
[<00000000fc8c2284>] __ieee80211_subif_start_xmit+0x30c/0x764
[<000000005926ee38>] ieee80211_subif_start_xmit+0x9c/0x7a4
[<000000004c86e916>] dev_hard_start_xmit+0x174/0x440
[<0000000023495647>] __dev_queue_xmit+0xe24/0x111c
[<00000000cfe9ca78>] batadv_send_skb_packet+0x180/0x1e4
[<000000007bacc5d5>] batadv_v_elp_periodic_work+0x2f4/0x508
[<00000000adc3cd94>] process_one_work+0x4b8/0xa1c
[<00000000b36425d1>] worker_thread+0x9c/0x634
[<0000000005852dd5>] kthread+0x1bc/0x1c4
[<000000005fccd770>] ret_from_fork+0x10/0x20
unreferenced object 0xffff000009051f00 (size 128):
comm "kworker/u8:4", pid 67, jiffies 4295419553 (age 1836.440s)
hex dump (first 32 bytes):
90 d6 92 0d 00 00 ff ff 00 d8 68 06 00 00 ff ff ..........h.....
36 27 92 e4 02 e0 01 00 00 58 79 06 00 00 ff ff 6'.......Xy.....
backtrace:
[<000000007302a0b6>] __kmem_cache_alloc_node+0x1e0/0x35c
[<00000000049bd418>] kmalloc_trace+0x34/0x80
[<0000000000d792bb>] mesh_queue_preq+0x44/0x2a8
[<00000000c99c3696>] mesh_nexthop_resolve+0x198/0x19c
[<00000000926bf598>] ieee80211_xmit+0x1d0/0x1f4
[<00000000fc8c2284>] __ieee80211_subif_start_xmit+0x30c/0x764
[<000000005926ee38>] ieee80211_subif_start_xmit+0x9c/0x7a4
[<000000004c86e916>] dev_hard_start_xmit+0x174/0x440
[<0000000023495647>] __dev_queue_xmit+0xe24/0x111c
[<00000000cfe9ca78>] batadv_send_skb_packet+0x180/0x1e4
[<000000007bacc5d5>] batadv_v_elp_periodic_work+0x2f4/0x508
[<00000000adc3cd94>] process_one_work+0x4b8/0xa1c
[<00000000b36425d1>] worker_thread+0x9c/0x634
[<0000000005852dd5>] kthread+0x1bc/0x1c4
[<000000005fccd770>] ret_from_fork+0x10/0x20
CVSS Score
5.5
EPSS Score
0.0
Published
2024-07-12
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix races between hole punching and AIO+DIO
After commit "ocfs2: return real error code in ocfs2_dio_wr_get_block",
fstests/generic/300 become from always failed to sometimes failed:
========================================================================
[ 473.293420 ] run fstests generic/300
[ 475.296983 ] JBD2: Ignoring recovery information on journal
[ 475.302473 ] ocfs2: Mounting device (253,1) on (node local, slot 0) with ordered data mode.
[ 494.290998 ] OCFS2: ERROR (device dm-1): ocfs2_change_extent_flag: Owner 5668 has an extent at cpos 78723 which can no longer be found
[ 494.291609 ] On-disk corruption discovered. Please run fsck.ocfs2 once the filesystem is unmounted.
[ 494.292018 ] OCFS2: File system is now read-only.
[ 494.292224 ] (kworker/19:11,2628,19):ocfs2_mark_extent_written:5272 ERROR: status = -30
[ 494.292602 ] (kworker/19:11,2628,19):ocfs2_dio_end_io_write:2374 ERROR: status = -3
fio: io_u error on file /mnt/scratch/racer: Read-only file system: write offset=460849152, buflen=131072
=========================================================================
In __blockdev_direct_IO, ocfs2_dio_wr_get_block is called to add unwritten
extents to a list. extents are also inserted into extent tree in
ocfs2_write_begin_nolock. Then another thread call fallocate to puch a
hole at one of the unwritten extent. The extent at cpos was removed by
ocfs2_remove_extent(). At end io worker thread, ocfs2_search_extent_list
found there is no such extent at the cpos.
T1 T2 T3
inode lock
...
insert extents
...
inode unlock
ocfs2_fallocate
__ocfs2_change_file_space
inode lock
lock ip_alloc_sem
ocfs2_remove_inode_range inode
ocfs2_remove_btree_range
ocfs2_remove_extent
^---remove the extent at cpos 78723
...
unlock ip_alloc_sem
inode unlock
ocfs2_dio_end_io
ocfs2_dio_end_io_write
lock ip_alloc_sem
ocfs2_mark_extent_written
ocfs2_change_extent_flag
ocfs2_search_extent_list
^---failed to find extent
...
unlock ip_alloc_sem
In most filesystems, fallocate is not compatible with racing with AIO+DIO,
so fix it by adding to wait for all dio before fallocate/punch_hole like
ext4.
CVSS Score
4.7
EPSS Score
0.0
Published
2024-07-12
In the Linux kernel, the following vulnerability has been resolved:
drm/exynos/vidi: fix memory leak in .get_modes()
The duplicated EDID is never freed. Fix it.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-07-12
In the Linux kernel, the following vulnerability has been resolved:
parisc: Try to fix random segmentation faults in package builds
PA-RISC systems with PA8800 and PA8900 processors have had problems
with random segmentation faults for many years. Systems with earlier
processors are much more stable.
Systems with PA8800 and PA8900 processors have a large L2 cache which
needs per page flushing for decent performance when a large range is
flushed. The combined cache in these systems is also more sensitive to
non-equivalent aliases than the caches in earlier systems.
The majority of random segmentation faults that I have looked at
appear to be memory corruption in memory allocated using mmap and
malloc.
My first attempt at fixing the random faults didn't work. On
reviewing the cache code, I realized that there were two issues
which the existing code didn't handle correctly. Both relate
to cache move-in. Another issue is that the present bit in PTEs
is racy.
1) PA-RISC caches have a mind of their own and they can speculatively
load data and instructions for a page as long as there is a entry in
the TLB for the page which allows move-in. TLBs are local to each
CPU. Thus, the TLB entry for a page must be purged before flushing
the page. This is particularly important on SMP systems.
In some of the flush routines, the flush routine would be called
and then the TLB entry would be purged. This was because the flush
routine needed the TLB entry to do the flush.
2) My initial approach to trying the fix the random faults was to
try and use flush_cache_page_if_present for all flush operations.
This actually made things worse and led to a couple of hardware
lockups. It finally dawned on me that some lines weren't being
flushed because the pte check code was racy. This resulted in
random inequivalent mappings to physical pages.
The __flush_cache_page tmpalias flush sets up its own TLB entry
and it doesn't need the existing TLB entry. As long as we can find
the pte pointer for the vm page, we can get the pfn and physical
address of the page. We can also purge the TLB entry for the page
before doing the flush. Further, __flush_cache_page uses a special
TLB entry that inhibits cache move-in.
When switching page mappings, we need to ensure that lines are
removed from the cache. It is not sufficient to just flush the
lines to memory as they may come back.
This made it clear that we needed to implement all the required
flush operations using tmpalias routines. This includes flushes
for user and kernel pages.
After modifying the code to use tmpalias flushes, it became clear
that the random segmentation faults were not fully resolved. The
frequency of faults was worse on systems with a 64 MB L2 (PA8900)
and systems with more CPUs (rp4440).
The warning that I added to flush_cache_page_if_present to detect
pages that couldn't be flushed triggered frequently on some systems.
Helge and I looked at the pages that couldn't be flushed and found
that the PTE was either cleared or for a swap page. Ignoring pages
that were swapped out seemed okay but pages with cleared PTEs seemed
problematic.
I looked at routines related to pte_clear and noticed ptep_clear_flush.
The default implementation just flushes the TLB entry. However, it was
obvious that on parisc we need to flush the cache page as well. If
we don't flush the cache page, stale lines will be left in the cache
and cause random corruption. Once a PTE is cleared, there is no way
to find the physical address associated with the PTE and flush the
associated page at a later time.
I implemented an updated change with a parisc specific version of
ptep_clear_flush. It fixed the random data corruption on Helge's rp4440
and rp3440, as well as on my c8000.
At this point, I realized that I could restore the code where we only
flush in flush_cache_page_if_present if the page has been accessed.
However, for this, we also need to flush the cache when the accessed
bit is cleared in
---truncated---
CVSS Score
6.3
EPSS Score
0.0
Published
2024-07-12
In the Linux kernel, the following vulnerability has been resolved:
jfs: xattr: fix buffer overflow for invalid xattr
When an xattr size is not what is expected, it is printed out to the
kernel log in hex format as a form of debugging. But when that xattr
size is bigger than the expected size, printing it out can cause an
access off the end of the buffer.
Fix this all up by properly restricting the size of the debug hex dump
in the kernel log.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-07-12
In the Linux kernel, the following vulnerability has been resolved:
USB: class: cdc-wdm: Fix CPU lockup caused by excessive log messages
The syzbot fuzzer found that the interrupt-URB completion callback in
the cdc-wdm driver was taking too long, and the driver's immediate
resubmission of interrupt URBs with -EPROTO status combined with the
dummy-hcd emulation to cause a CPU lockup:
cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625]
CPU#0 Utilization every 4s during lockup:
#1: 98% system, 0% softirq, 3% hardirq, 0% idle
#2: 98% system, 0% softirq, 3% hardirq, 0% idle
#3: 98% system, 0% softirq, 3% hardirq, 0% idle
#4: 98% system, 0% softirq, 3% hardirq, 0% idle
#5: 98% system, 1% softirq, 3% hardirq, 0% idle
Modules linked in:
irq event stamp: 73096
hardirqs last enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline]
hardirqs last enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994
hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline]
softirqs last enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582
softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588
CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G W 6.10.0-rc2-syzkaller-g8867bbd4a056 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Testing showed that the problem did not occur if the two error
messages -- the first two lines above -- were removed; apparently adding
material to the kernel log takes a surprisingly large amount of time.
In any case, the best approach for preventing these lockups and to
avoid spamming the log with thousands of error messages per second is
to ratelimit the two dev_err() calls. Therefore we replace them with
dev_err_ratelimited().
CVSS Score
5.5
EPSS Score
0.0
Published
2024-07-12
In the Linux kernel, the following vulnerability has been resolved:
ima: Fix use-after-free on a dentry's dname.name
->d_name.name can change on rename and the earlier value can be freed;
there are conditions sufficient to stabilize it (->d_lock on dentry,
->d_lock on its parent, ->i_rwsem exclusive on the parent's inode,
rename_lock), but none of those are met at any of the sites. Take a stable
snapshot of the name instead.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-07-12
In the Linux kernel, the following vulnerability has been resolved:
greybus: Fix use-after-free bug in gb_interface_release due to race condition.
In gb_interface_create, &intf->mode_switch_completion is bound with
gb_interface_mode_switch_work. Then it will be started by
gb_interface_request_mode_switch. Here is the relevant code.
if (!queue_work(system_long_wq, &intf->mode_switch_work)) {
...
}
If we call gb_interface_release to make cleanup, there may be an
unfinished work. This function will call kfree to free the object
"intf". However, if gb_interface_mode_switch_work is scheduled to
run after kfree, it may cause use-after-free error as
gb_interface_mode_switch_work will use the object "intf".
The possible execution flow that may lead to the issue is as follows:
CPU0 CPU1
| gb_interface_create
| gb_interface_request_mode_switch
gb_interface_release |
kfree(intf) (free) |
| gb_interface_mode_switch_work
| mutex_lock(&intf->mutex) (use)
Fix it by canceling the work before kfree.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-07-12
In the Linux kernel, the following vulnerability has been resolved:
btrfs: zoned: fix use-after-free due to race with dev replace
While loading a zone's info during creation of a block group, we can race
with a device replace operation and then trigger a use-after-free on the
device that was just replaced (source device of the replace operation).
This happens because at btrfs_load_zone_info() we extract a device from
the chunk map into a local variable and then use the device while not
under the protection of the device replace rwsem. So if there's a device
replace operation happening when we extract the device and that device
is the source of the replace operation, we will trigger a use-after-free
if before we finish using the device the replace operation finishes and
frees the device.
Fix this by enlarging the critical section under the protection of the
device replace rwsem so that all uses of the device are done inside the
critical section.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-07-12
In the Linux kernel, the following vulnerability has been resolved:
xfs: fix log recovery buffer allocation for the legacy h_size fixup
Commit a70f9fe52daa ("xfs: detect and handle invalid iclog size set by
mkfs") added a fixup for incorrect h_size values used for the initial
umount record in old xfsprogs versions. Later commit 0c771b99d6c9
("xfs: clean up calculation of LR header blocks") cleaned up the log
reover buffer calculation, but stoped using the fixed up h_size value
to size the log recovery buffer, which can lead to an out of bounds
access when the incorrect h_size does not come from the old mkfs
tool, but a fuzzer.
Fix this by open coding xlog_logrec_hblks and taking the fixed h_size
into account for this calculation.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-07-05