Linux: >> Linux Kernel >> 2.6.37.1 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
cdrom: rearrange last_media_change check to avoid unintentional overflow
When running syzkaller with the newly reintroduced signed integer wrap
sanitizer we encounter this splat:
[ 366.015950] UBSAN: signed-integer-overflow in ../drivers/cdrom/cdrom.c:2361:33
[ 366.021089] -9223372036854775808 - 346321 cannot be represented in type '__s64' (aka 'long long')
[ 366.025894] program syz-executor.4 is using a deprecated SCSI ioctl, please convert it to SG_IO
[ 366.027502] CPU: 5 PID: 28472 Comm: syz-executor.7 Not tainted 6.8.0-rc2-00035-gb3ef86b5a957 #1
[ 366.027512] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 366.027518] Call Trace:
[ 366.027523] <TASK>
[ 366.027533] dump_stack_lvl+0x93/0xd0
[ 366.027899] handle_overflow+0x171/0x1b0
[ 366.038787] ata1.00: invalid multi_count 32 ignored
[ 366.043924] cdrom_ioctl+0x2c3f/0x2d10
[ 366.063932] ? __pm_runtime_resume+0xe6/0x130
[ 366.071923] sr_block_ioctl+0x15d/0x1d0
[ 366.074624] ? __pfx_sr_block_ioctl+0x10/0x10
[ 366.077642] blkdev_ioctl+0x419/0x500
[ 366.080231] ? __pfx_blkdev_ioctl+0x10/0x10
...
Historically, the signed integer overflow sanitizer did not work in the
kernel due to its interaction with `-fwrapv` but this has since been
changed [1] in the newest version of Clang. It was re-enabled in the
kernel with Commit 557f8c582a9ba8ab ("ubsan: Reintroduce signed overflow
sanitizer").
Let's rearrange the check to not perform any arithmetic, thus not
tripping the sanitizer.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-07-30
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Add NULL pointer check for kzalloc
[Why & How]
Check return pointer of kzalloc before using it.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-07-30
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: fix double free err_addr pointer warnings
In amdgpu_umc_bad_page_polling_timeout, the amdgpu_umc_handle_bad_pages
will be run many times so that double free err_addr in some special case.
So set the err_addr to NULL to avoid the warnings.
CVSS Score
4.4
EPSS Score
0.0
Published
2024-07-30
In the Linux kernel, the following vulnerability has been resolved:
drm/nouveau: fix null pointer dereference in nouveau_connector_get_modes
In nouveau_connector_get_modes(), the return value of drm_mode_duplicate()
is assigned to mode, which will lead to a possible NULL pointer
dereference on failure of drm_mode_duplicate(). Add a check to avoid npd.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-07-30
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: add missing check for inode numbers on directory entries
Syzbot reported that mounting and unmounting a specific pattern of
corrupted nilfs2 filesystem images causes a use-after-free of metadata
file inodes, which triggers a kernel bug in lru_add_fn().
As Jan Kara pointed out, this is because the link count of a metadata file
gets corrupted to 0, and nilfs_evict_inode(), which is called from iput(),
tries to delete that inode (ifile inode in this case).
The inconsistency occurs because directories containing the inode numbers
of these metadata files that should not be visible in the namespace are
read without checking.
Fix this issue by treating the inode numbers of these internal files as
errors in the sanity check helper when reading directory folios/pages.
Also thanks to Hillf Danton and Matthew Wilcox for their initial mm-layer
analysis.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-07-30
In the Linux kernel, the following vulnerability has been resolved:
x86: stop playing stack games in profile_pc()
The 'profile_pc()' function is used for timer-based profiling, which
isn't really all that relevant any more to begin with, but it also ends
up making assumptions based on the stack layout that aren't necessarily
valid.
Basically, the code tries to account the time spent in spinlocks to the
caller rather than the spinlock, and while I support that as a concept,
it's not worth the code complexity or the KASAN warnings when no serious
profiling is done using timers anyway these days.
And the code really does depend on stack layout that is only true in the
simplest of cases. We've lost the comment at some point (I think when
the 32-bit and 64-bit code was unified), but it used to say:
Assume the lock function has either no stack frame or a copy
of eflags from PUSHF.
which explains why it just blindly loads a word or two straight off the
stack pointer and then takes a minimal look at the values to just check
if they might be eflags or the return pc:
Eflags always has bits 22 and up cleared unlike kernel addresses
but that basic stack layout assumption assumes that there isn't any lock
debugging etc going on that would complicate the code and cause a stack
frame.
It causes KASAN unhappiness reported for years by syzkaller [1] and
others [2].
With no real practical reason for this any more, just remove the code.
Just for historical interest, here's some background commits relating to
this code from 2006:
0cb91a229364 ("i386: Account spinlocks to the caller during profiling for !FP kernels")
31679f38d886 ("Simplify profile_pc on x86-64")
and a code unification from 2009:
ef4512882dbe ("x86: time_32/64.c unify profile_pc")
but the basics of this thing actually goes back to before the git tree.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-07-29
In the Linux kernel, the following vulnerability has been resolved:
net/dpaa2: Avoid explicit cpumask var allocation on stack
For CONFIG_CPUMASK_OFFSTACK=y kernel, explicit allocation of cpumask
variable on stack is not recommended since it can cause potential stack
overflow.
Instead, kernel code should always use *cpumask_var API(s) to allocate
cpumask var in config-neutral way, leaving allocation strategy to
CONFIG_CPUMASK_OFFSTACK.
Use *cpumask_var API(s) to address it.
CVSS Score
7.3
EPSS Score
0.0
Published
2024-07-29
In the Linux kernel, the following vulnerability has been resolved:
net/iucv: Avoid explicit cpumask var allocation on stack
For CONFIG_CPUMASK_OFFSTACK=y kernel, explicit allocation of cpumask
variable on stack is not recommended since it can cause potential stack
overflow.
Instead, kernel code should always use *cpumask_var API(s) to allocate
cpumask var in config-neutral way, leaving allocation strategy to
CONFIG_CPUMASK_OFFSTACK.
Use *cpumask_var API(s) to address it.
CVSS Score
7.1
EPSS Score
0.0
Published
2024-07-29
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix DIO failure due to insufficient transaction credits
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits(). This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.
Extent tree manipulations do often extend the current transaction but not
in all of the cases. For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents. Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error. This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.
To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().
Heming Zhao said:
------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"
PID: xxx TASK: xxxx CPU: 5 COMMAND: "SubmitThread-CA"
#0 machine_kexec at ffffffff8c069932
#1 __crash_kexec at ffffffff8c1338fa
#2 panic at ffffffff8c1d69b9
#3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
#4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
#5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
#6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
#7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
#8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
#9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba
CVSS Score
5.5
EPSS Score
0.0
Published
2024-07-29
In the Linux kernel, the following vulnerability has been resolved:
nfsd: initialise nfsd_info.mutex early.
nfsd_info.mutex can be dereferenced by svc_pool_stats_start()
immediately after the new netns is created. Currently this can
trigger an oops.
Move the initialisation earlier before it can possibly be dereferenced.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-07-29