| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
bfq: Update cgroup information before merging bio
When the process is migrated to a different cgroup (or in case of
writeback just starts submitting bios associated with a different
cgroup) bfq_merge_bio() can operate with stale cgroup information in
bic. Thus the bio can be merged to a request from a different cgroup or
it can result in merging of bfqqs for different cgroups or bfqqs of
already dead cgroups and causing possible use-after-free issues. Fix the
problem by updating cgroup information in bfq_merge_bio(). |
| In the Linux kernel, the following vulnerability has been resolved:
bfq: Make sure bfqg for which we are queueing requests is online
Bios queued into BFQ IO scheduler can be associated with a cgroup that
was already offlined. This may then cause insertion of this bfq_group
into a service tree. But this bfq_group will get freed as soon as last
bio associated with it is completed leading to use after free issues for
service tree users. Fix the problem by making sure we always operate on
online bfq_group. If the bfq_group associated with the bio is not
online, we pick the first online parent. |
| In the Linux kernel, the following vulnerability has been resolved:
ubi: ubi_create_volume: Fix use-after-free when volume creation failed
There is an use-after-free problem for 'eba_tbl' in ubi_create_volume()'s
error handling path:
ubi_eba_replace_table(vol, eba_tbl)
vol->eba_tbl = tbl
out_mapping:
ubi_eba_destroy_table(eba_tbl) // Free 'eba_tbl'
out_unlock:
put_device(&vol->dev)
vol_release
kfree(tbl->entries) // UAF
Fix it by removing redundant 'eba_tbl' releasing.
Fetch a reproducer in [Link]. |
| In the Linux kernel, the following vulnerability has been resolved:
driver: base: fix UAF when driver_attach failed
When driver_attach(drv); failed, the driver_private will be freed.
But it has been added to the bus, which caused a UAF.
To fix it, we need to delete it from the bus when failed. |
| In the Linux kernel, the following vulnerability has been resolved:
blk-mq: don't touch ->tagset in blk_mq_get_sq_hctx
blk_mq_run_hw_queues() could be run when there isn't queued request and
after queue is cleaned up, at that time tagset is freed, because tagset
lifetime is covered by driver, and often freed after blk_cleanup_queue()
returns.
So don't touch ->tagset for figuring out current default hctx by the mapping
built in request queue, so use-after-free on tagset can be avoided. Meantime
this way should be fast than retrieving mapping from tagset. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: Fix potential use-after-free in nfsd_file_put()
nfsd_file_put_noref() can free @nf, so don't dereference @nf
immediately upon return from nfsd_file_put_noref(). |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix use-after-free in ext4_rename_dir_prepare
We got issue as follows:
EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue
ext4_get_first_dir_block: bh->b_data=0xffff88810bee6000 len=34478
ext4_get_first_dir_block: *parent_de=0xffff88810beee6ae bh->b_data=0xffff88810bee6000
ext4_rename_dir_prepare: [1] parent_de=0xffff88810beee6ae
==================================================================
BUG: KASAN: use-after-free in ext4_rename_dir_prepare+0x152/0x220
Read of size 4 at addr ffff88810beee6ae by task rep/1895
CPU: 13 PID: 1895 Comm: rep Not tainted 5.10.0+ #241
Call Trace:
dump_stack+0xbe/0xf9
print_address_description.constprop.0+0x1e/0x220
kasan_report.cold+0x37/0x7f
ext4_rename_dir_prepare+0x152/0x220
ext4_rename+0xf44/0x1ad0
ext4_rename2+0x11c/0x170
vfs_rename+0xa84/0x1440
do_renameat2+0x683/0x8f0
__x64_sys_renameat+0x53/0x60
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f45a6fc41c9
RSP: 002b:00007ffc5a470218 EFLAGS: 00000246 ORIG_RAX: 0000000000000108
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f45a6fc41c9
RDX: 0000000000000005 RSI: 0000000020000180 RDI: 0000000000000005
RBP: 00007ffc5a470240 R08: 00007ffc5a470160 R09: 0000000020000080
R10: 00000000200001c0 R11: 0000000000000246 R12: 0000000000400bb0
R13: 00007ffc5a470320 R14: 0000000000000000 R15: 0000000000000000
The buggy address belongs to the page:
page:00000000440015ce refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x10beee
flags: 0x200000000000000()
raw: 0200000000000000 ffffea00043ff4c8 ffffea0004325608 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88810beee580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88810beee600: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88810beee680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff88810beee700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88810beee780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
Disabling lock debugging due to kernel taint
ext4_rename_dir_prepare: [2] parent_de->inode=3537895424
ext4_rename_dir_prepare: [3] dir=0xffff888124170140
ext4_rename_dir_prepare: [4] ino=2
ext4_rename_dir_prepare: ent->dir->i_ino=2 parent=-757071872
Reason is first directory entry which 'rec_len' is 34478, then will get illegal
parent entry. Now, we do not check directory entry after read directory block
in 'ext4_get_first_dir_block'.
To solve this issue, check directory entry in 'ext4_get_first_dir_block'.
[ Trigger an ext4_error() instead of just warning if the directory is
missing a '.' or '..' entry. Also make sure we return an error code
if the file system is corrupted. -TYT ] |
| In the Linux kernel, the following vulnerability has been resolved:
mt76: fix use-after-free by removing a non-RCU wcid pointer
Fixes an issue caught by KASAN about use-after-free in mt76_txq_schedule
by protecting mtxq->wcid with rcu_lock between mt76_txq_schedule and
sta_info_[alloc, free].
[18853.876689] ==================================================================
[18853.876751] BUG: KASAN: use-after-free in mt76_txq_schedule+0x204/0xaf8 [mt76]
[18853.876773] Read of size 8 at addr ffffffaf989a2138 by task mt76-tx phy0/883
[18853.876786]
[18853.876810] CPU: 5 PID: 883 Comm: mt76-tx phy0 Not tainted 5.10.100-fix-510-56778d365941-kasan #5 0b01fbbcf41a530f52043508fec2e31a4215
[18853.876840] Call trace:
[18853.876861] dump_backtrace+0x0/0x3ec
[18853.876878] show_stack+0x20/0x2c
[18853.876899] dump_stack+0x11c/0x1ac
[18853.876918] print_address_description+0x74/0x514
[18853.876934] kasan_report+0x134/0x174
[18853.876948] __asan_report_load8_noabort+0x44/0x50
[18853.876976] mt76_txq_schedule+0x204/0xaf8 [mt76 074e03e4640e97fe7405ee1fab547b81c4fa45d2]
[18853.877002] mt76_txq_schedule_all+0x2c/0x48 [mt76 074e03e4640e97fe7405ee1fab547b81c4fa45d2]
[18853.877030] mt7921_tx_worker+0xa0/0x1cc [mt7921_common f0875ebac9d7b4754e1010549e7db50fbd90a047]
[18853.877054] __mt76_worker_fn+0x190/0x22c [mt76 074e03e4640e97fe7405ee1fab547b81c4fa45d2]
[18853.877071] kthread+0x2f8/0x3b8
[18853.877087] ret_from_fork+0x10/0x30
[18853.877098]
[18853.877112] Allocated by task 941:
[18853.877131] kasan_save_stack+0x38/0x68
[18853.877147] __kasan_kmalloc+0xd4/0xfc
[18853.877163] kasan_kmalloc+0x10/0x1c
[18853.877177] __kmalloc+0x264/0x3c4
[18853.877294] sta_info_alloc+0x460/0xf88 [mac80211]
[18853.877410] ieee80211_prep_connection+0x204/0x1ee0 [mac80211]
[18853.877523] ieee80211_mgd_auth+0x6c4/0xa4c [mac80211]
[18853.877635] ieee80211_auth+0x20/0x2c [mac80211]
[18853.877733] rdev_auth+0x7c/0x438 [cfg80211]
[18853.877826] cfg80211_mlme_auth+0x26c/0x390 [cfg80211]
[18853.877919] nl80211_authenticate+0x6d4/0x904 [cfg80211]
[18853.877938] genl_rcv_msg+0x748/0x93c
[18853.877954] netlink_rcv_skb+0x160/0x2a8
[18853.877969] genl_rcv+0x3c/0x54
[18853.877985] netlink_unicast_kernel+0x104/0x1ec
[18853.877999] netlink_unicast+0x178/0x268
[18853.878015] netlink_sendmsg+0x3cc/0x5f0
[18853.878030] sock_sendmsg+0xb4/0xd8
[18853.878043] ____sys_sendmsg+0x2f8/0x53c
[18853.878058] ___sys_sendmsg+0xe8/0x150
[18853.878071] __sys_sendmsg+0xc4/0x1f4
[18853.878087] __arm64_compat_sys_sendmsg+0x88/0x9c
[18853.878101] el0_svc_common+0x1b4/0x390
[18853.878115] do_el0_svc_compat+0x8c/0xdc
[18853.878131] el0_svc_compat+0x10/0x1c
[18853.878146] el0_sync_compat_handler+0xa8/0xcc
[18853.878161] el0_sync_compat+0x188/0x1c0
[18853.878171]
[18853.878183] Freed by task 10927:
[18853.878200] kasan_save_stack+0x38/0x68
[18853.878215] kasan_set_track+0x28/0x3c
[18853.878228] kasan_set_free_info+0x24/0x48
[18853.878244] __kasan_slab_free+0x11c/0x154
[18853.878259] kasan_slab_free+0x14/0x24
[18853.878273] slab_free_freelist_hook+0xac/0x1b0
[18853.878287] kfree+0x104/0x390
[18853.878402] sta_info_free+0x198/0x210 [mac80211]
[18853.878515] __sta_info_destroy_part2+0x230/0x2d4 [mac80211]
[18853.878628] __sta_info_flush+0x300/0x37c [mac80211]
[18853.878740] ieee80211_set_disassoc+0x2cc/0xa7c [mac80211]
[18853.878851] ieee80211_mgd_deauth+0x4a4/0x10a0 [mac80211]
[18853.878962] ieee80211_deauth+0x20/0x2c [mac80211]
[18853.879057] rdev_deauth+0x7c/0x438 [cfg80211]
[18853.879150] cfg80211_mlme_deauth+0x274/0x414 [cfg80211]
[18853.879243] cfg80211_mlme_down+0xe4/0x118 [cfg80211]
[18853.879335] cfg80211_disconnect+0x218/0x2d8 [cfg80211]
[18853.879427] __cfg80211_leave+0x17c/0x240 [cfg80211]
[18853.879519] cfg80211_leave+0x3c/0x58 [cfg80211]
[18853.879611] wiphy_suspend+0xdc/0x200 [cfg80211]
[18853.879628] dpm_run_callback+0x58/0x408
[18853.879642] __device_suspend+0x4cc/0x864
[18853.879658] async_suspend+0x34/0xf4
[18
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
drivers: staging: rtl8723bs: Fix deadlock in rtw_surveydone_event_callback()
There is a deadlock in rtw_surveydone_event_callback(),
which is shown below:
(Thread 1) | (Thread 2)
| _set_timer()
rtw_surveydone_event_callback()| mod_timer()
spin_lock_bh() //(1) | (wait a time)
... | rtw_scan_timeout_handler()
del_timer_sync() | spin_lock_bh() //(2)
(wait timer to stop) | ...
We hold pmlmepriv->lock in position (1) of thread 1 and use
del_timer_sync() to wait timer to stop, but timer handler
also need pmlmepriv->lock in position (2) of thread 2.
As a result, rtw_surveydone_event_callback() will block forever.
This patch extracts del_timer_sync() from the protection of
spin_lock_bh(), which could let timer handler to obtain
the needed lock. What`s more, we change spin_lock_bh() in
rtw_scan_timeout_handler() to spin_lock_irq(). Otherwise,
spin_lock_bh() will also cause deadlock() in timer handler. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: pcm: Fix races among concurrent hw_params and hw_free calls
Currently we have neither proper check nor protection against the
concurrent calls of PCM hw_params and hw_free ioctls, which may result
in a UAF. Since the existing PCM stream lock can't be used for
protecting the whole ioctl operations, we need a new mutex to protect
those racy calls.
This patch introduced a new mutex, runtime->buffer_mutex, and applies
it to both hw_params and hw_free ioctl code paths. Along with it, the
both functions are slightly modified (the mmap_count check is moved
into the state-check block) for code simplicity. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: pcm: Fix races among concurrent prealloc proc writes
We have no protection against concurrent PCM buffer preallocation
changes via proc files, and it may potentially lead to UAF or some
weird problem. This patch applies the PCM open_mutex to the proc
write operation for avoiding the racy proc writes and the PCM stream
open (and further operations). |
| In the Linux kernel, the following vulnerability has been resolved:
tpm: fix reference counting for struct tpm_chip
The following sequence of operations results in a refcount warning:
1. Open device /dev/tpmrm.
2. Remove module tpm_tis_spi.
3. Write a TPM command to the file descriptor opened at step 1.
------------[ cut here ]------------
WARNING: CPU: 3 PID: 1161 at lib/refcount.c:25 kobject_get+0xa0/0xa4
refcount_t: addition on 0; use-after-free.
Modules linked in: tpm_tis_spi tpm_tis_core tpm mdio_bcm_unimac brcmfmac
sha256_generic libsha256 sha256_arm hci_uart btbcm bluetooth cfg80211 vc4
brcmutil ecdh_generic ecc snd_soc_core crc32_arm_ce libaes
raspberrypi_hwmon ac97_bus snd_pcm_dmaengine bcm2711_thermal snd_pcm
snd_timer genet snd phy_generic soundcore [last unloaded: spi_bcm2835]
CPU: 3 PID: 1161 Comm: hold_open Not tainted 5.10.0ls-main-dirty #2
Hardware name: BCM2711
[<c0410c3c>] (unwind_backtrace) from [<c040b580>] (show_stack+0x10/0x14)
[<c040b580>] (show_stack) from [<c1092174>] (dump_stack+0xc4/0xd8)
[<c1092174>] (dump_stack) from [<c0445a30>] (__warn+0x104/0x108)
[<c0445a30>] (__warn) from [<c0445aa8>] (warn_slowpath_fmt+0x74/0xb8)
[<c0445aa8>] (warn_slowpath_fmt) from [<c08435d0>] (kobject_get+0xa0/0xa4)
[<c08435d0>] (kobject_get) from [<bf0a715c>] (tpm_try_get_ops+0x14/0x54 [tpm])
[<bf0a715c>] (tpm_try_get_ops [tpm]) from [<bf0a7d6c>] (tpm_common_write+0x38/0x60 [tpm])
[<bf0a7d6c>] (tpm_common_write [tpm]) from [<c05a7ac0>] (vfs_write+0xc4/0x3c0)
[<c05a7ac0>] (vfs_write) from [<c05a7ee4>] (ksys_write+0x58/0xcc)
[<c05a7ee4>] (ksys_write) from [<c04001a0>] (ret_fast_syscall+0x0/0x4c)
Exception stack(0xc226bfa8 to 0xc226bff0)
bfa0: 00000000 000105b4 00000003 beafe664 00000014 00000000
bfc0: 00000000 000105b4 000103f8 00000004 00000000 00000000 b6f9c000 beafe684
bfe0: 0000006c beafe648 0001056c b6eb6944
---[ end trace d4b8409def9b8b1f ]---
The reason for this warning is the attempt to get the chip->dev reference
in tpm_common_write() although the reference counter is already zero.
Since commit 8979b02aaf1d ("tpm: Fix reference count to main device") the
extra reference used to prevent a premature zero counter is never taken,
because the required TPM_CHIP_FLAG_TPM2 flag is never set.
Fix this by moving the TPM 2 character device handling from
tpm_chip_alloc() to tpm_add_char_device() which is called at a later point
in time when the flag has been set in case of TPM2.
Commit fdc915f7f719 ("tpm: expose spaces via a device link /dev/tpmrm<n>")
already introduced function tpm_devs_release() to release the extra
reference but did not implement the required put on chip->devs that results
in the call of this function.
Fix this by putting chip->devs in tpm_chip_unregister().
Finally move the new implementation for the TPM 2 handling into a new
function to avoid multiple checks for the TPM_CHIP_FLAG_TPM2 flag in the
good case and error cases. |
| In the Linux kernel, the following vulnerability has been resolved:
can: m_can: m_can_tx_handler(): fix use after free of skb
can_put_echo_skb() will clone skb then free the skb. Move the
can_put_echo_skb() for the m_can version 3.0.x directly before the
start of the xmit in hardware, similar to the 3.1.x branch. |
| In the Linux kernel, the following vulnerability has been resolved:
dm: fix use-after-free in dm_cleanup_zoned_dev()
dm_cleanup_zoned_dev() uses queue, so it must be called
before blk_cleanup_disk() starts its killing:
blk_cleanup_disk->blk_cleanup_queue()->kobject_put()->blk_release_queue()->
->...RCU...->blk_free_queue_rcu()->kmem_cache_free()
Otherwise, RCU callback may be executed first and
dm_cleanup_zoned_dev() will touch free'd memory:
BUG: KASAN: use-after-free in dm_cleanup_zoned_dev+0x33/0xd0
Read of size 8 at addr ffff88805ac6e430 by task dmsetup/681
CPU: 4 PID: 681 Comm: dmsetup Not tainted 5.17.0-rc2+ #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x57/0x7d
print_address_description.constprop.0+0x1f/0x150
? dm_cleanup_zoned_dev+0x33/0xd0
kasan_report.cold+0x7f/0x11b
? dm_cleanup_zoned_dev+0x33/0xd0
dm_cleanup_zoned_dev+0x33/0xd0
__dm_destroy+0x26a/0x400
? dm_blk_ioctl+0x230/0x230
? up_write+0xd8/0x270
dev_remove+0x156/0x1d0
ctl_ioctl+0x269/0x530
? table_clear+0x140/0x140
? lock_release+0xb2/0x750
? remove_all+0x40/0x40
? rcu_read_lock_sched_held+0x12/0x70
? lock_downgrade+0x3c0/0x3c0
? rcu_read_lock_sched_held+0x12/0x70
dm_ctl_ioctl+0xa/0x10
__x64_sys_ioctl+0xb9/0xf0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fb6dfa95c27 |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: ccree - Fix use after free in cc_cipher_exit()
kfree_sensitive(ctx_p->user.key) will free the ctx_p->user.key. But
ctx_p->user.key is still used in the next line, which will lead to a
use after free.
We can call kfree_sensitive() after dev_dbg() to avoid the uaf. |
| In the Linux kernel, the following vulnerability has been resolved:
ath11k: free peer for station when disconnect from AP for QCA6390/WCN6855
Commit b4a0f54156ac ("ath11k: move peer delete after vdev stop of station
for QCA6390 and WCN6855") is to fix firmware crash by changing the WMI
command sequence, but actually skip all the peer delete operation, then
it lead commit 58595c9874c6 ("ath11k: Fixing dangling pointer issue upon
peer delete failure") not take effect, and then happened a use-after-free
warning from KASAN. because the peer->sta is not set to NULL and then used
later.
Change to only skip the WMI_PEER_DELETE_CMDID for QCA6390/WCN6855.
log of user-after-free:
[ 534.888665] BUG: KASAN: use-after-free in ath11k_dp_rx_update_peer_stats+0x912/0xc10 [ath11k]
[ 534.888696] Read of size 8 at addr ffff8881396bb1b8 by task rtcwake/2860
[ 534.888705] CPU: 4 PID: 2860 Comm: rtcwake Kdump: loaded Tainted: G W 5.15.0-wt-ath+ #523
[ 534.888712] Hardware name: Intel(R) Client Systems NUC8i7HVK/NUC8i7HVB, BIOS HNKBLi70.86A.0067.2021.0528.1339 05/28/2021
[ 534.888716] Call Trace:
[ 534.888720] <IRQ>
[ 534.888726] dump_stack_lvl+0x57/0x7d
[ 534.888736] print_address_description.constprop.0+0x1f/0x170
[ 534.888745] ? ath11k_dp_rx_update_peer_stats+0x912/0xc10 [ath11k]
[ 534.888771] kasan_report.cold+0x83/0xdf
[ 534.888783] ? ath11k_dp_rx_update_peer_stats+0x912/0xc10 [ath11k]
[ 534.888810] ath11k_dp_rx_update_peer_stats+0x912/0xc10 [ath11k]
[ 534.888840] ath11k_dp_rx_process_mon_status+0x529/0xa70 [ath11k]
[ 534.888874] ? ath11k_dp_rx_mon_status_bufs_replenish+0x3f0/0x3f0 [ath11k]
[ 534.888897] ? check_prev_add+0x20f0/0x20f0
[ 534.888922] ? __lock_acquire+0xb72/0x1870
[ 534.888937] ? find_held_lock+0x33/0x110
[ 534.888954] ath11k_dp_rx_process_mon_rings+0x297/0x520 [ath11k]
[ 534.888981] ? rcu_read_unlock+0x40/0x40
[ 534.888990] ? ath11k_dp_rx_pdev_alloc+0xd90/0xd90 [ath11k]
[ 534.889026] ath11k_dp_service_mon_ring+0x67/0xe0 [ath11k]
[ 534.889053] ? ath11k_dp_rx_process_mon_rings+0x520/0x520 [ath11k]
[ 534.889075] call_timer_fn+0x167/0x4a0
[ 534.889084] ? add_timer_on+0x3b0/0x3b0
[ 534.889103] ? lockdep_hardirqs_on_prepare.part.0+0x18c/0x370
[ 534.889117] __run_timers.part.0+0x539/0x8b0
[ 534.889123] ? ath11k_dp_rx_process_mon_rings+0x520/0x520 [ath11k]
[ 534.889157] ? call_timer_fn+0x4a0/0x4a0
[ 534.889164] ? mark_lock_irq+0x1c30/0x1c30
[ 534.889173] ? clockevents_program_event+0xdd/0x280
[ 534.889189] ? mark_held_locks+0xa5/0xe0
[ 534.889203] run_timer_softirq+0x97/0x180
[ 534.889213] __do_softirq+0x276/0x86a
[ 534.889230] __irq_exit_rcu+0x11c/0x180
[ 534.889238] irq_exit_rcu+0x5/0x20
[ 534.889244] sysvec_apic_timer_interrupt+0x8e/0xc0
[ 534.889251] </IRQ>
[ 534.889254] <TASK>
[ 534.889259] asm_sysvec_apic_timer_interrupt+0x12/0x20
[ 534.889265] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70
[ 534.889271] Code: 74 24 10 e8 ea c2 bf fd 48 89 ef e8 12 53 c0 fd 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 13 a7 b5 fd 65 8b 05 cc d9 9c 5e 85 c0 74 0a 5b 5d c3 e8 a0 ee
[ 534.889276] RSP: 0018:ffffc90002e5f880 EFLAGS: 00000206
[ 534.889284] RAX: 0000000000000006 RBX: 0000000000000200 RCX: ffffffff9f256f10
[ 534.889289] RDX: 0000000000000000 RSI: ffffffffa1c6e420 RDI: 0000000000000001
[ 534.889293] RBP: ffff8881095e6200 R08: 0000000000000001 R09: ffffffffa40d2b8f
[ 534.889298] R10: fffffbfff481a571 R11: 0000000000000001 R12: ffff8881095e6e68
[ 534.889302] R13: ffffc90002e5f908 R14: 0000000000000246 R15: 0000000000000000
[ 534.889316] ? mark_lock+0xd0/0x14a0
[ 534.889332] klist_next+0x1d4/0x450
[ 534.889340] ? dpm_wait_for_subordinate+0x2d0/0x2d0
[ 534.889350] device_for_each_child+0xa8/0x140
[ 534.889360] ? device_remove_class_symlinks+0x1b0/0x1b0
[ 534.889370] ? __lock_release+0x4bd/0x9f0
[ 534.889378] ? dpm_suspend+0x26b/0x3f0
[ 534.889390] dpm_wait_for_subordinate+
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix UAF due to race between btf_try_get_module and load_module
While working on code to populate kfunc BTF ID sets for module BTF from
its initcall, I noticed that by the time the initcall is invoked, the
module BTF can already be seen by userspace (and the BPF verifier). The
existing btf_try_get_module calls try_module_get which only fails if
mod->state == MODULE_STATE_GOING, i.e. it can increment module reference
when module initcall is happening in parallel.
Currently, BTF parsing happens from MODULE_STATE_COMING notifier
callback. At this point, the module initcalls have not been invoked.
The notifier callback parses and prepares the module BTF, allocates an
ID, which publishes it to userspace, and then adds it to the btf_modules
list allowing the kernel to invoke btf_try_get_module for the BTF.
However, at this point, the module has not been fully initialized (i.e.
its initcalls have not finished). The code in module.c can still fail
and free the module, without caring for other users. However, nothing
stops btf_try_get_module from succeeding between the state transition
from MODULE_STATE_COMING to MODULE_STATE_LIVE.
This leads to a use-after-free issue when BPF program loads
successfully in the state transition, load_module's do_init_module call
fails and frees the module, and BPF program fd on close calls module_put
for the freed module. Future patch has test case to verify we don't
regress in this area in future.
There are multiple points after prepare_coming_module (in load_module)
where failure can occur and module loading can return error. We
illustrate and test for the race using the last point where it can
practically occur (in module __init function).
An illustration of the race:
CPU 0 CPU 1
load_module
notifier_call(MODULE_STATE_COMING)
btf_parse_module
btf_alloc_id // Published to userspace
list_add(&btf_mod->list, btf_modules)
mod->init(...)
... ^
bpf_check |
check_pseudo_btf_id |
btf_try_get_module |
returns true | ...
... | module __init in progress
return prog_fd | ...
... V
if (ret < 0)
free_module(mod)
...
close(prog_fd)
...
bpf_prog_free_deferred
module_put(used_btf.mod) // use-after-free
We fix this issue by setting a flag BTF_MODULE_F_LIVE, from the notifier
callback when MODULE_STATE_LIVE state is reached for the module, so that
we return NULL from btf_try_get_module for modules that are not fully
formed. Since try_module_get already checks that module is not in
MODULE_STATE_GOING state, and that is the only transition a live module
can make before being removed from btf_modules list, this is enough to
close the race and prevent the bug.
A later selftest patch crafts the race condition artifically to verify
that it has been fixed, and that verifier fails to load program (with
ENXIO).
Lastly, a couple of comments:
1. Even if this race didn't exist, it seems more appropriate to only
access resources (ksyms and kfuncs) of a fully formed module which
has been initialized completely.
2. This patch was born out of need for synchronization against module
initcall for the next patch, so it is needed for correctness even
without the aforementioned race condition. The BTF resources
initialized by module initcall are set up once and then only looked
up, so just waiting until the initcall has finished ensures correct
behavior. |
| In the Linux kernel, the following vulnerability has been resolved:
cxl/port: Hold port reference until decoder release
KASAN + DEBUG_KOBJECT_RELEASE reports a potential use-after-free in
cxl_decoder_release() where it goes to reference its parent, a cxl_port,
to free its id back to port->decoder_ida.
BUG: KASAN: use-after-free in to_cxl_port+0x18/0x90 [cxl_core]
Read of size 8 at addr ffff888119270908 by task kworker/35:2/379
CPU: 35 PID: 379 Comm: kworker/35:2 Tainted: G OE 5.17.0-rc2+ #198
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Workqueue: events kobject_delayed_cleanup
Call Trace:
<TASK>
dump_stack_lvl+0x59/0x73
print_address_description.constprop.0+0x1f/0x150
? to_cxl_port+0x18/0x90 [cxl_core]
kasan_report.cold+0x83/0xdf
? to_cxl_port+0x18/0x90 [cxl_core]
to_cxl_port+0x18/0x90 [cxl_core]
cxl_decoder_release+0x2a/0x60 [cxl_core]
device_release+0x5f/0x100
kobject_cleanup+0x80/0x1c0
The device core only guarantees parent lifetime until all children are
unregistered. If a child needs a parent to complete its ->release()
callback that child needs to hold a reference to extend the lifetime of
the parent. |
| In the Linux kernel, the following vulnerability has been resolved:
vfio/pci: fix memory leak during D3hot to D0 transition
If 'vfio_pci_core_device::needs_pm_restore' is set (PCI device does
not have No_Soft_Reset bit set in its PMCSR config register), then
the current PCI state will be saved locally in
'vfio_pci_core_device::pm_save' during D0->D3hot transition and same
will be restored back during D3hot->D0 transition.
For saving the PCI state locally, pci_store_saved_state() is being
used and the pci_load_and_free_saved_state() will free the allocated
memory.
But for reset related IOCTLs, vfio driver calls PCI reset-related
API's which will internally change the PCI power state back to D0. So,
when the guest resumes, then it will get the current state as D0 and it
will skip the call to vfio_pci_set_power_state() for changing the
power state to D0 explicitly. In this case, the memory pointed by
'pm_save' will never be freed. In a malicious sequence, the state changing
to D3hot followed by VFIO_DEVICE_RESET/VFIO_DEVICE_PCI_HOT_RESET can be
run in a loop and it can cause an OOM situation.
This patch frees the earlier allocated memory first before overwriting
'pm_save' to prevent the mentioned memory leak. |
| In the Linux kernel, the following vulnerability has been resolved:
kernel/resource: fix kfree() of bootmem memory again
Since commit ebff7d8f270d ("mem hotunplug: fix kfree() of bootmem
memory"), we could get a resource allocated during boot via
alloc_resource(). And it's required to release the resource using
free_resource(). Howerver, many people use kfree directly which will
result in kernel BUG. In order to fix this without fixing every call
site, just leak a couple of bytes in such corner case. |
