| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| Git is a revision control system. Prior to versions 2.30.9, 2.31.8, 2.32.7, 2.33.8, 2.34.8, 2.35.8, 2.36.6, 2.37.7, 2.38.5, 2.39.3, and 2.40.1, by feeding specially crafted input to `git apply --reject`, a path outside the working tree can be overwritten with partially controlled contents (corresponding to the rejected hunk(s) from the given patch). A fix is available in versions 2.30.9, 2.31.8, 2.32.7, 2.33.8, 2.34.8, 2.35.8, 2.36.6, 2.37.7, 2.38.5, 2.39.3, and 2.40.1. As a workaround, avoid using `git apply` with `--reject` when applying patches from an untrusted source. Use `git apply --stat` to inspect a patch before applying; avoid applying one that create a conflict where a link corresponding to the `*.rej` file exists. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/msm/gem: Fix error code msm_parse_deps()
The SUBMIT_ERROR() macro turns the error code negative. This extra '-'
operation turns it back to positive EINVAL again. The error code is
passed to ERR_PTR() and since positive values are not an IS_ERR() it
eventually will lead to an oops. Delete the '-'.
Patchwork: https://patchwork.freedesktop.org/patch/637625/ |
| In the Linux kernel, the following vulnerability has been resolved:
net: libwx: fix Tx L4 checksum
The hardware only supports L4 checksum offload for TCP/UDP/SCTP protocol.
There was a bug to set Tx checksum flag for the other protocol that results
in Tx ring hang. Fix to compute software checksum for these packets. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btnxpuart: Fix kernel panic during FW release
This fixes a kernel panic seen during release FW in a stress test
scenario where WLAN and BT FW download occurs simultaneously, and due to
a HW bug, chip sends out only 1 bootloader signatures.
When driver receives the bootloader signature, it enters FW download
mode, but since no consequtive bootloader signatures seen, FW file is
not requested.
After 60 seconds, when FW download times out, release_firmware causes a
kernel panic.
[ 2601.949184] Unable to handle kernel paging request at virtual address 0000312e6f006573
[ 2601.992076] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000111802000
[ 2601.992080] [0000312e6f006573] pgd=0000000000000000, p4d=0000000000000000
[ 2601.992087] Internal error: Oops: 0000000096000021 [#1] PREEMPT SMP
[ 2601.992091] Modules linked in: algif_hash algif_skcipher af_alg btnxpuart(O) pciexxx(O) mlan(O) overlay fsl_jr_uio caam_jr caamkeyblob_desc caamhash_desc caamalg_desc crypto_engine authenc libdes crct10dif_ce polyval_ce snd_soc_fsl_easrc snd_soc_fsl_asoc_card imx8_media_dev(C) snd_soc_fsl_micfil polyval_generic snd_soc_fsl_xcvr snd_soc_fsl_sai snd_soc_imx_audmux snd_soc_fsl_asrc snd_soc_imx_card snd_soc_imx_hdmi snd_soc_fsl_aud2htx snd_soc_fsl_utils imx_pcm_dma dw_hdmi_cec flexcan can_dev
[ 2602.001825] CPU: 2 PID: 20060 Comm: hciconfig Tainted: G C O 6.6.23-lts-next-06236-gb586a521770e #1
[ 2602.010182] Hardware name: NXP i.MX8MPlus EVK board (DT)
[ 2602.010185] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 2602.010191] pc : _raw_spin_lock+0x34/0x68
[ 2602.010201] lr : free_fw_priv+0x20/0xfc
[ 2602.020561] sp : ffff800089363b30
[ 2602.020563] x29: ffff800089363b30 x28: ffff0000d0eb5880 x27: 0000000000000000
[ 2602.020570] x26: 0000000000000000 x25: ffff0000d728b330 x24: 0000000000000000
[ 2602.020577] x23: ffff0000dc856f38
[ 2602.033797] x22: ffff800089363b70 x21: ffff0000dc856000
[ 2602.033802] x20: ff00312e6f006573 x19: ffff0000d0d9ea80 x18: 0000000000000000
[ 2602.033809] x17: 0000000000000000 x16: 0000000000000000 x15: 0000aaaad80dd480
[ 2602.083320] x14: 0000000000000000 x13: 00000000000001b9 x12: 0000000000000002
[ 2602.083326] x11: 0000000000000000 x10: 0000000000000a60 x9 : ffff800089363a30
[ 2602.083333] x8 : ffff0001793d75c0 x7 : ffff0000d6dbc400 x6 : 0000000000000000
[ 2602.083339] x5 : 00000000410fd030 x4 : 0000000000000000 x3 : 0000000000000001
[ 2602.083346] x2 : 0000000000000000 x1 : 0000000000000001 x0 : ff00312e6f006573
[ 2602.083354] Call trace:
[ 2602.083356] _raw_spin_lock+0x34/0x68
[ 2602.083364] release_firmware+0x48/0x6c
[ 2602.083370] nxp_setup+0x3c4/0x540 [btnxpuart]
[ 2602.083383] hci_dev_open_sync+0xf0/0xa34
[ 2602.083391] hci_dev_open+0xd8/0x178
[ 2602.083399] hci_sock_ioctl+0x3b0/0x590
[ 2602.083405] sock_do_ioctl+0x60/0x118
[ 2602.083413] sock_ioctl+0x2f4/0x374
[ 2602.091430] __arm64_sys_ioctl+0xac/0xf0
[ 2602.091437] invoke_syscall+0x48/0x110
[ 2602.091445] el0_svc_common.constprop.0+0xc0/0xe0
[ 2602.091452] do_el0_svc+0x1c/0x28
[ 2602.091457] el0_svc+0x40/0xe4
[ 2602.091465] el0t_64_sync_handler+0x120/0x12c
[ 2602.091470] el0t_64_sync+0x190/0x194 |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid panic once fallocation fails for pinfile
syzbot reports a f2fs bug as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:2746!
CPU: 0 UID: 0 PID: 5323 Comm: syz.0.0 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0
RIP: 0010:get_new_segment fs/f2fs/segment.c:2746 [inline]
RIP: 0010:new_curseg+0x1f52/0x1f70 fs/f2fs/segment.c:2876
Call Trace:
<TASK>
__allocate_new_segment+0x1ce/0x940 fs/f2fs/segment.c:3210
f2fs_allocate_new_section fs/f2fs/segment.c:3224 [inline]
f2fs_allocate_pinning_section+0xfa/0x4e0 fs/f2fs/segment.c:3238
f2fs_expand_inode_data+0x696/0xca0 fs/f2fs/file.c:1830
f2fs_fallocate+0x537/0xa10 fs/f2fs/file.c:1940
vfs_fallocate+0x569/0x6e0 fs/open.c:327
do_vfs_ioctl+0x258c/0x2e40 fs/ioctl.c:885
__do_sys_ioctl fs/ioctl.c:904 [inline]
__se_sys_ioctl+0x80/0x170 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Concurrent pinfile allocation may run out of free section, result in
panic in get_new_segment(), let's expand pin_sem lock coverage to
include f2fs_gc(), so that we can make sure to reclaim enough free
space for following allocation.
In addition, do below changes to enhance error path handling:
- call f2fs_bug_on() only in non-pinfile allocation path in
get_new_segment().
- call reset_curseg_fields() to reset all fields of curseg in
new_curseg() |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: quota: fix to avoid warning in dquot_writeback_dquots()
F2FS-fs (dm-59): checkpoint=enable has some unwritten data.
------------[ cut here ]------------
WARNING: CPU: 6 PID: 8013 at fs/quota/dquot.c:691 dquot_writeback_dquots+0x2fc/0x308
pc : dquot_writeback_dquots+0x2fc/0x308
lr : f2fs_quota_sync+0xcc/0x1c4
Call trace:
dquot_writeback_dquots+0x2fc/0x308
f2fs_quota_sync+0xcc/0x1c4
f2fs_write_checkpoint+0x3d4/0x9b0
f2fs_issue_checkpoint+0x1bc/0x2c0
f2fs_sync_fs+0x54/0x150
f2fs_do_sync_file+0x2f8/0x814
__f2fs_ioctl+0x1960/0x3244
f2fs_ioctl+0x54/0xe0
__arm64_sys_ioctl+0xa8/0xe4
invoke_syscall+0x58/0x114
checkpoint and f2fs_remount may race as below, resulting triggering warning
in dquot_writeback_dquots().
atomic write remount
- do_remount
- down_write(&sb->s_umount);
- f2fs_remount
- ioctl
- f2fs_do_sync_file
- f2fs_sync_fs
- f2fs_write_checkpoint
- block_operations
- locked = down_read_trylock(&sbi->sb->s_umount)
: fail to lock due to the write lock was held by remount
- up_write(&sb->s_umount);
- f2fs_quota_sync
- dquot_writeback_dquots
- WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount))
: trigger warning because s_umount lock was unlocked by remount
If checkpoint comes from mount/umount/remount/freeze/quotactl, caller of
checkpoint has already held s_umount lock, calling dquot_writeback_dquots()
in the context should be safe.
So let's record task to sbi->umount_lock_holder, so that checkpoint can
know whether the lock has held in the context or not by checking current
w/ it.
In addition, in order to not misrepresent caller of checkpoint, we should
not allow to trigger async checkpoint for those callers: mount/umount/remount/
freeze/quotactl. |
| In the Linux kernel, the following vulnerability has been resolved:
RISC-V: KVM: Teardown riscv specific bits after kvm_exit
During a module removal, kvm_exit invokes arch specific disable
call which disables AIA. However, we invoke aia_exit before kvm_exit
resulting in the following warning. KVM kernel module can't be inserted
afterwards due to inconsistent state of IRQ.
[25469.031389] percpu IRQ 31 still enabled on CPU0!
[25469.031732] WARNING: CPU: 3 PID: 943 at kernel/irq/manage.c:2476 __free_percpu_irq+0xa2/0x150
[25469.031804] Modules linked in: kvm(-)
[25469.031848] CPU: 3 UID: 0 PID: 943 Comm: rmmod Not tainted 6.14.0-rc5-06947-g91c763118f47-dirty #2
[25469.031905] Hardware name: riscv-virtio,qemu (DT)
[25469.031928] epc : __free_percpu_irq+0xa2/0x150
[25469.031976] ra : __free_percpu_irq+0xa2/0x150
[25469.032197] epc : ffffffff8007db1e ra : ffffffff8007db1e sp : ff2000000088bd50
[25469.032241] gp : ffffffff8131cef8 tp : ff60000080b96400 t0 : ff2000000088baf8
[25469.032285] t1 : fffffffffffffffc t2 : 5249207570637265 s0 : ff2000000088bd90
[25469.032329] s1 : ff60000098b21080 a0 : 037d527a15eb4f00 a1 : 037d527a15eb4f00
[25469.032372] a2 : 0000000000000023 a3 : 0000000000000001 a4 : ffffffff8122dbf8
[25469.032410] a5 : 0000000000000fff a6 : 0000000000000000 a7 : ffffffff8122dc10
[25469.032448] s2 : ff60000080c22eb0 s3 : 0000000200000022 s4 : 000000000000001f
[25469.032488] s5 : ff60000080c22e00 s6 : ffffffff80c351c0 s7 : 0000000000000000
[25469.032582] s8 : 0000000000000003 s9 : 000055556b7fb490 s10: 00007ffff0e12fa0
[25469.032621] s11: 00007ffff0e13e9a t3 : ffffffff81354ac7 t4 : ffffffff81354ac7
[25469.032664] t5 : ffffffff81354ac8 t6 : ffffffff81354ac7
[25469.032698] status: 0000000200000100 badaddr: ffffffff8007db1e cause: 0000000000000003
[25469.032738] [<ffffffff8007db1e>] __free_percpu_irq+0xa2/0x150
[25469.032797] [<ffffffff8007dbfc>] free_percpu_irq+0x30/0x5e
[25469.032856] [<ffffffff013a57dc>] kvm_riscv_aia_exit+0x40/0x42 [kvm]
[25469.033947] [<ffffffff013b4e82>] cleanup_module+0x10/0x32 [kvm]
[25469.035300] [<ffffffff8009b150>] __riscv_sys_delete_module+0x18e/0x1fc
[25469.035374] [<ffffffff8000c1ca>] syscall_handler+0x3a/0x46
[25469.035456] [<ffffffff809ec9a4>] do_trap_ecall_u+0x72/0x134
[25469.035536] [<ffffffff809f5e18>] handle_exception+0x148/0x156
Invoke aia_exit and other arch specific cleanup functions after kvm_exit
so that disable gets a chance to be called first before exit. |
| In the Linux kernel, the following vulnerability has been resolved:
watch_queue: fix pipe accounting mismatch
Currently, watch_queue_set_size() modifies the pipe buffers charged to
user->pipe_bufs without updating the pipe->nr_accounted on the pipe
itself, due to the if (!pipe_has_watch_queue()) test in
pipe_resize_ring(). This means that when the pipe is ultimately freed,
we decrement user->pipe_bufs by something other than what than we had
charged to it, potentially leading to an underflow. This in turn can
cause subsequent too_many_pipe_buffers_soft() tests to fail with -EPERM.
To remedy this, explicitly account for the pipe usage in
watch_queue_set_size() to match the number set via account_pipe_buffers()
(It's unclear why watch_queue_set_size() does not update nr_accounted;
it may be due to intentional overprovisioning in watch_queue_set_size()?) |
| IBM Data Risk Manager 2.0.1, 2.0.2, 2.0.3, 2.0.4, 2.0.5, and 2.0.6 could allow a remote attacker to bypass security restrictions when configured with SAML authentication. By sending a specially crafted HTTP request, an attacker could exploit this vulnerability to bypass the authentication process and gain full administrative access to the system. IBM X-Force ID: 180532. |
| A flaw was found in OpenStack due to an inconsistency between Cinder and Nova. This issue can be triggered intentionally or by accident. A remote, authenticated attacker could exploit this vulnerability by detaching one of their volumes from Cinder. The highest impact is to confidentiality. |
| An issue was found in Git before v2.24.1, v2.23.1, v2.22.2, v2.21.1, v2.20.2, v2.19.3, v2.18.2, v2.17.3, v2.16.6, v2.15.4, and v2.14.6. Recursive clones are currently affected by a vulnerability that is caused by too-lax validation of submodule names, allowing very targeted attacks via remote code execution in recursive clones. |
| BlueZ HID over GATT Profile Improper Access Control Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of BlueZ. Authentication is not required to exploit this vulnerability.
The specific flaw exists within the implementation of the HID over GATT Profile. The issue results from the lack of authorization prior to allowing access to functionality. An attacker can leverage this vulnerability to execute code in the context of the current user. Was ZDI-CAN-25177. |
| When almost out-of-memory an elliptic curve key which was never allocated could have been freed again. This vulnerability affects Firefox < 128 and Thunderbird < 128. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_event: Align BR/EDR JUST_WORKS paring with LE
This aligned BR/EDR JUST_WORKS method with LE which since 92516cd97fd4
("Bluetooth: Always request for user confirmation for Just Works")
always request user confirmation with confirm_hint set since the
likes of bluetoothd have dedicated policy around JUST_WORKS method
(e.g. main.conf:JustWorksRepairing).
CVE: CVE-2024-8805 |
| In the Linux kernel, the following vulnerability has been resolved:
netlink: terminate outstanding dump on socket close
Netlink supports iterative dumping of data. It provides the families
the following ops:
- start - (optional) kicks off the dumping process
- dump - actual dump helper, keeps getting called until it returns 0
- done - (optional) pairs with .start, can be used for cleanup
The whole process is asynchronous and the repeated calls to .dump
don't actually happen in a tight loop, but rather are triggered
in response to recvmsg() on the socket.
This gives the user full control over the dump, but also means that
the user can close the socket without getting to the end of the dump.
To make sure .start is always paired with .done we check if there
is an ongoing dump before freeing the socket, and if so call .done.
The complication is that sockets can get freed from BH and .done
is allowed to sleep. So we use a workqueue to defer the call, when
needed.
Unfortunately this does not work correctly. What we defer is not
the cleanup but rather releasing a reference on the socket.
We have no guarantee that we own the last reference, if someone
else holds the socket they may release it in BH and we're back
to square one.
The whole dance, however, appears to be unnecessary. Only the user
can interact with dumps, so we can clean up when socket is closed.
And close always happens in process context. Some async code may
still access the socket after close, queue notification skbs to it etc.
but no dumps can start, end or otherwise make progress.
Delete the workqueue and flush the dump state directly from the release
handler. Note that further cleanup is possible in -next, for instance
we now always call .done before releasing the main module reference,
so dump doesn't have to take a reference of its own. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Bury Intel PT virtualization (guest/host mode) behind CONFIG_BROKEN
Hide KVM's pt_mode module param behind CONFIG_BROKEN, i.e. disable support
for virtualizing Intel PT via guest/host mode unless BROKEN=y. There are
myriad bugs in the implementation, some of which are fatal to the guest,
and others which put the stability and health of the host at risk.
For guest fatalities, the most glaring issue is that KVM fails to ensure
tracing is disabled, and *stays* disabled prior to VM-Enter, which is
necessary as hardware disallows loading (the guest's) RTIT_CTL if tracing
is enabled (enforced via a VMX consistency check). Per the SDM:
If the logical processor is operating with Intel PT enabled (if
IA32_RTIT_CTL.TraceEn = 1) at the time of VM entry, the "load
IA32_RTIT_CTL" VM-entry control must be 0.
On the host side, KVM doesn't validate the guest CPUID configuration
provided by userspace, and even worse, uses the guest configuration to
decide what MSRs to save/load at VM-Enter and VM-Exit. E.g. configuring
guest CPUID to enumerate more address ranges than are supported in hardware
will result in KVM trying to passthrough, save, and load non-existent MSRs,
which generates a variety of WARNs, ToPA ERRORs in the host, a potential
deadlock, etc. |
| In the Linux kernel, the following vulnerability has been resolved:
Revert "mmc: dw_mmc: Fix IDMAC operation with pages bigger than 4K"
The commit 8396c793ffdf ("mmc: dw_mmc: Fix IDMAC operation with pages
bigger than 4K") increased the max_req_size, even for 4K pages, causing
various issues:
- Panic booting the kernel/rootfs from an SD card on Rockchip RK3566
- Panic booting the kernel/rootfs from an SD card on StarFive JH7100
- "swiotlb buffer is full" and data corruption on StarFive JH7110
At this stage no fix have been found, so it's probably better to just
revert the change.
This reverts commit 8396c793ffdf28bb8aee7cfe0891080f8cab7890. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: uncache inode which has failed entering the group
Syzbot has reported the following BUG:
kernel BUG at fs/ocfs2/uptodate.c:509!
...
Call Trace:
<TASK>
? __die_body+0x5f/0xb0
? die+0x9e/0xc0
? do_trap+0x15a/0x3a0
? ocfs2_set_new_buffer_uptodate+0x145/0x160
? do_error_trap+0x1dc/0x2c0
? ocfs2_set_new_buffer_uptodate+0x145/0x160
? __pfx_do_error_trap+0x10/0x10
? handle_invalid_op+0x34/0x40
? ocfs2_set_new_buffer_uptodate+0x145/0x160
? exc_invalid_op+0x38/0x50
? asm_exc_invalid_op+0x1a/0x20
? ocfs2_set_new_buffer_uptodate+0x2e/0x160
? ocfs2_set_new_buffer_uptodate+0x144/0x160
? ocfs2_set_new_buffer_uptodate+0x145/0x160
ocfs2_group_add+0x39f/0x15a0
? __pfx_ocfs2_group_add+0x10/0x10
? __pfx_lock_acquire+0x10/0x10
? mnt_get_write_access+0x68/0x2b0
? __pfx_lock_release+0x10/0x10
? rcu_read_lock_any_held+0xb7/0x160
? __pfx_rcu_read_lock_any_held+0x10/0x10
? smack_log+0x123/0x540
? mnt_get_write_access+0x68/0x2b0
? mnt_get_write_access+0x68/0x2b0
? mnt_get_write_access+0x226/0x2b0
ocfs2_ioctl+0x65e/0x7d0
? __pfx_ocfs2_ioctl+0x10/0x10
? smack_file_ioctl+0x29e/0x3a0
? __pfx_smack_file_ioctl+0x10/0x10
? lockdep_hardirqs_on_prepare+0x43d/0x780
? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
? __pfx_ocfs2_ioctl+0x10/0x10
__se_sys_ioctl+0xfb/0x170
do_syscall_64+0xf3/0x230
entry_SYSCALL_64_after_hwframe+0x77/0x7f
...
</TASK>
When 'ioctl(OCFS2_IOC_GROUP_ADD, ...)' has failed for the particular
inode in 'ocfs2_verify_group_and_input()', corresponding buffer head
remains cached and subsequent call to the same 'ioctl()' for the same
inode issues the BUG() in 'ocfs2_set_new_buffer_uptodate()' (trying
to cache the same buffer head of that inode). Fix this by uncaching
the buffer head with 'ocfs2_remove_from_cache()' on error path in
'ocfs2_group_add()'. |
| In the Linux kernel, the following vulnerability has been resolved:
mm: krealloc: Fix MTE false alarm in __do_krealloc
This patch addresses an issue introduced by commit 1a83a716ec233 ("mm:
krealloc: consider spare memory for __GFP_ZERO") which causes MTE
(Memory Tagging Extension) to falsely report a slab-out-of-bounds error.
The problem occurs when zeroing out spare memory in __do_krealloc. The
original code only considered software-based KASAN and did not account
for MTE. It does not reset the KASAN tag before calling memset, leading
to a mismatch between the pointer tag and the memory tag, resulting
in a false positive.
Example of the error:
==================================================================
swapper/0: BUG: KASAN: slab-out-of-bounds in __memset+0x84/0x188
swapper/0: Write at addr f4ffff8005f0fdf0 by task swapper/0/1
swapper/0: Pointer tag: [f4], memory tag: [fe]
swapper/0:
swapper/0: CPU: 4 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.
swapper/0: Hardware name: MT6991(ENG) (DT)
swapper/0: Call trace:
swapper/0: dump_backtrace+0xfc/0x17c
swapper/0: show_stack+0x18/0x28
swapper/0: dump_stack_lvl+0x40/0xa0
swapper/0: print_report+0x1b8/0x71c
swapper/0: kasan_report+0xec/0x14c
swapper/0: __do_kernel_fault+0x60/0x29c
swapper/0: do_bad_area+0x30/0xdc
swapper/0: do_tag_check_fault+0x20/0x34
swapper/0: do_mem_abort+0x58/0x104
swapper/0: el1_abort+0x3c/0x5c
swapper/0: el1h_64_sync_handler+0x80/0xcc
swapper/0: el1h_64_sync+0x68/0x6c
swapper/0: __memset+0x84/0x188
swapper/0: btf_populate_kfunc_set+0x280/0x3d8
swapper/0: __register_btf_kfunc_id_set+0x43c/0x468
swapper/0: register_btf_kfunc_id_set+0x48/0x60
swapper/0: register_nf_nat_bpf+0x1c/0x40
swapper/0: nf_nat_init+0xc0/0x128
swapper/0: do_one_initcall+0x184/0x464
swapper/0: do_initcall_level+0xdc/0x1b0
swapper/0: do_initcalls+0x70/0xc0
swapper/0: do_basic_setup+0x1c/0x28
swapper/0: kernel_init_freeable+0x144/0x1b8
swapper/0: kernel_init+0x20/0x1a8
swapper/0: ret_from_fork+0x10/0x20
================================================================== |
| In the Linux kernel, the following vulnerability has been resolved:
mm: resolve faulty mmap_region() error path behaviour
The mmap_region() function is somewhat terrifying, with spaghetti-like
control flow and numerous means by which issues can arise and incomplete
state, memory leaks and other unpleasantness can occur.
A large amount of the complexity arises from trying to handle errors late
in the process of mapping a VMA, which forms the basis of recently
observed issues with resource leaks and observable inconsistent state.
Taking advantage of previous patches in this series we move a number of
checks earlier in the code, simplifying things by moving the core of the
logic into a static internal function __mmap_region().
Doing this allows us to perform a number of checks up front before we do
any real work, and allows us to unwind the writable unmap check
unconditionally as required and to perform a CONFIG_DEBUG_VM_MAPLE_TREE
validation unconditionally also.
We move a number of things here:
1. We preallocate memory for the iterator before we call the file-backed
memory hook, allowing us to exit early and avoid having to perform
complicated and error-prone close/free logic. We carefully free
iterator state on both success and error paths.
2. The enclosing mmap_region() function handles the mapping_map_writable()
logic early. Previously the logic had the mapping_map_writable() at the
point of mapping a newly allocated file-backed VMA, and a matching
mapping_unmap_writable() on success and error paths.
We now do this unconditionally if this is a file-backed, shared writable
mapping. If a driver changes the flags to eliminate VM_MAYWRITE, however
doing so does not invalidate the seal check we just performed, and we in
any case always decrement the counter in the wrapper.
We perform a debug assert to ensure a driver does not attempt to do the
opposite.
3. We also move arch_validate_flags() up into the mmap_region()
function. This is only relevant on arm64 and sparc64, and the check is
only meaningful for SPARC with ADI enabled. We explicitly add a warning
for this arch if a driver invalidates this check, though the code ought
eventually to be fixed to eliminate the need for this.
With all of these measures in place, we no longer need to explicitly close
the VMA on error paths, as we place all checks which might fail prior to a
call to any driver mmap hook.
This eliminates an entire class of errors, makes the code easier to reason
about and more robust. |
