| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Zeroing allocated object from slab in bpf memory allocator
Currently the freed element in bpf memory allocator may be immediately
reused, for htab map the reuse will reinitialize special fields in map
value (e.g., bpf_spin_lock), but lookup procedure may still access
these special fields, and it may lead to hard-lockup as shown below:
NMI backtrace for cpu 16
CPU: 16 PID: 2574 Comm: htab.bin Tainted: G L 6.1.0+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
RIP: 0010:queued_spin_lock_slowpath+0x283/0x2c0
......
Call Trace:
<TASK>
copy_map_value_locked+0xb7/0x170
bpf_map_copy_value+0x113/0x3c0
__sys_bpf+0x1c67/0x2780
__x64_sys_bpf+0x1c/0x20
do_syscall_64+0x30/0x60
entry_SYSCALL_64_after_hwframe+0x46/0xb0
......
</TASK>
For htab map, just like the preallocated case, these is no need to
initialize these special fields in map value again once these fields
have been initialized. For preallocated htab map, these fields are
initialized through __GFP_ZERO in bpf_map_area_alloc(), so do the
similar thing for non-preallocated htab in bpf memory allocator. And
there is no need to use __GFP_ZERO for per-cpu bpf memory allocator,
because __alloc_percpu_gfp() does it implicitly. |
| In the Linux kernel, the following vulnerability has been resolved:
md: fix warning for holder mismatch from export_rdev()
Commit a1d767191096 ("md: use mddev->external to select holder in
export_rdev()") fix the problem that 'claim_rdev' is used for
blkdev_get_by_dev() while 'rdev' is used for blkdev_put().
However, if mddev->external is changed from 0 to 1, then 'rdev' is used
for blkdev_get_by_dev() while 'claim_rdev' is used for blkdev_put(). And
this problem can be reporduced reliably by following:
New file: mdadm/tests/23rdev-lifetime
devname=${dev0##*/}
devt=`cat /sys/block/$devname/dev`
pid=""
runtime=2
clean_up_test() {
pill -9 $pid
echo clear > /sys/block/md0/md/array_state
}
trap 'clean_up_test' EXIT
add_by_sysfs() {
while true; do
echo $devt > /sys/block/md0/md/new_dev
done
}
remove_by_sysfs(){
while true; do
echo remove > /sys/block/md0/md/dev-${devname}/state
done
}
echo md0 > /sys/module/md_mod/parameters/new_array || die "create md0 failed"
add_by_sysfs &
pid="$pid $!"
remove_by_sysfs &
pid="$pid $!"
sleep $runtime
exit 0
Test cmd:
./test --save-logs --logdir=/tmp/ --keep-going --dev=loop --tests=23rdev-lifetime
Test result:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 960 at block/bdev.c:618 blkdev_put+0x27c/0x330
Modules linked in: multipath md_mod loop
CPU: 0 PID: 960 Comm: test Not tainted 6.5.0-rc2-00121-g01e55c376936-dirty #50
RIP: 0010:blkdev_put+0x27c/0x330
Call Trace:
<TASK>
export_rdev.isra.23+0x50/0xa0 [md_mod]
mddev_unlock+0x19d/0x300 [md_mod]
rdev_attr_store+0xec/0x190 [md_mod]
sysfs_kf_write+0x52/0x70
kernfs_fop_write_iter+0x19a/0x2a0
vfs_write+0x3b5/0x770
ksys_write+0x74/0x150
__x64_sys_write+0x22/0x30
do_syscall_64+0x40/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fix the problem by recording if 'rdev' is used as holder. |
| In the Linux kernel, the following vulnerability has been resolved:
ethtool: Fix uninitialized number of lanes
It is not possible to set the number of lanes when setting link modes
using the legacy IOCTL ethtool interface. Since 'struct
ethtool_link_ksettings' is not initialized in this path, drivers receive
an uninitialized number of lanes in 'struct
ethtool_link_ksettings::lanes'.
When this information is later queried from drivers, it results in the
ethtool code making decisions based on uninitialized memory, leading to
the following KMSAN splat [1]. In practice, this most likely only
happens with the tun driver that simply returns whatever it got in the
set operation.
As far as I can tell, this uninitialized memory is not leaked to user
space thanks to the 'ethtool_ops->cap_link_lanes_supported' check in
linkmodes_prepare_data().
Fix by initializing the structure in the IOCTL path. Did not find any
more call sites that pass an uninitialized structure when calling
'ethtool_ops::set_link_ksettings()'.
[1]
BUG: KMSAN: uninit-value in ethnl_update_linkmodes net/ethtool/linkmodes.c:273 [inline]
BUG: KMSAN: uninit-value in ethnl_set_linkmodes+0x190b/0x19d0 net/ethtool/linkmodes.c:333
ethnl_update_linkmodes net/ethtool/linkmodes.c:273 [inline]
ethnl_set_linkmodes+0x190b/0x19d0 net/ethtool/linkmodes.c:333
ethnl_default_set_doit+0x88d/0xde0 net/ethtool/netlink.c:640
genl_family_rcv_msg_doit net/netlink/genetlink.c:968 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:1048 [inline]
genl_rcv_msg+0x141a/0x14c0 net/netlink/genetlink.c:1065
netlink_rcv_skb+0x3f8/0x750 net/netlink/af_netlink.c:2577
genl_rcv+0x40/0x60 net/netlink/genetlink.c:1076
netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
netlink_unicast+0xf41/0x1270 net/netlink/af_netlink.c:1365
netlink_sendmsg+0x127d/0x1430 net/netlink/af_netlink.c:1942
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
____sys_sendmsg+0xa24/0xe40 net/socket.c:2501
___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2555
__sys_sendmsg net/socket.c:2584 [inline]
__do_sys_sendmsg net/socket.c:2593 [inline]
__se_sys_sendmsg net/socket.c:2591 [inline]
__x64_sys_sendmsg+0x36b/0x540 net/socket.c:2591
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Uninit was stored to memory at:
tun_get_link_ksettings+0x37/0x60 drivers/net/tun.c:3544
__ethtool_get_link_ksettings+0x17b/0x260 net/ethtool/ioctl.c:441
ethnl_set_linkmodes+0xee/0x19d0 net/ethtool/linkmodes.c:327
ethnl_default_set_doit+0x88d/0xde0 net/ethtool/netlink.c:640
genl_family_rcv_msg_doit net/netlink/genetlink.c:968 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:1048 [inline]
genl_rcv_msg+0x141a/0x14c0 net/netlink/genetlink.c:1065
netlink_rcv_skb+0x3f8/0x750 net/netlink/af_netlink.c:2577
genl_rcv+0x40/0x60 net/netlink/genetlink.c:1076
netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
netlink_unicast+0xf41/0x1270 net/netlink/af_netlink.c:1365
netlink_sendmsg+0x127d/0x1430 net/netlink/af_netlink.c:1942
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
____sys_sendmsg+0xa24/0xe40 net/socket.c:2501
___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2555
__sys_sendmsg net/socket.c:2584 [inline]
__do_sys_sendmsg net/socket.c:2593 [inline]
__se_sys_sendmsg net/socket.c:2591 [inline]
__x64_sys_sendmsg+0x36b/0x540 net/socket.c:2591
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Uninit was stored to memory at:
tun_set_link_ksettings+0x37/0x60 drivers/net/tun.c:3553
ethtool_set_link_ksettings+0x600/0x690 net/ethtool/ioctl.c:609
__dev_ethtool net/ethtool/ioctl.c:3024 [inline]
dev_ethtool+0x1db9/0x2a70 net/ethtool/ioctl.c:3078
dev_ioctl+0xb07/0x1270 net/core/dev_ioctl.c:524
sock_do_ioctl+0x295/0x540 net/socket.c:1213
sock_i
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: api - Use work queue in crypto_destroy_instance
The function crypto_drop_spawn expects to be called in process
context. However, when an instance is unregistered while it still
has active users, the last user may cause the instance to be freed
in atomic context.
Fix this by delaying the freeing to a work queue. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: ses: Fix slab-out-of-bounds in ses_enclosure_data_process()
A fix for:
BUG: KASAN: slab-out-of-bounds in ses_enclosure_data_process+0x949/0xe30 [ses]
Read of size 1 at addr ffff88a1b043a451 by task systemd-udevd/3271
Checking after (and before in next loop) addl_desc_ptr[1] is sufficient, we
expect the size to be sanitized before first access to addl_desc_ptr[1].
Make sure we don't walk beyond end of page. |
| In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix use-after-free bug of nilfs_root in nilfs_evict_inode()
During unmount process of nilfs2, nothing holds nilfs_root structure after
nilfs2 detaches its writer in nilfs_detach_log_writer(). However, since
nilfs_evict_inode() uses nilfs_root for some cleanup operations, it may
cause use-after-free read if inodes are left in "garbage_list" and
released by nilfs_dispose_list() at the end of nilfs_detach_log_writer().
Fix this issue by modifying nilfs_evict_inode() to only clear inode
without additional metadata changes that use nilfs_root if the file system
is degraded to read-only or the writer is detached. |
| In the Linux kernel, the following vulnerability has been resolved:
clk: clocking-wizard: Fix Oops in clk_wzrd_register_divider()
Smatch detected this potential error pointer dereference
clk_wzrd_register_divider(). If devm_clk_hw_register() fails then
it sets "hw" to an error pointer and then dereferences it on the
next line. Return the error directly instead. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mwifiex: fix memory leak in mwifiex_histogram_read()
Always free the zeroed page on return from 'mwifiex_histogram_read()'. |
| In the Linux kernel, the following vulnerability has been resolved:
blk-mq: release crypto keyslot before reporting I/O complete
Once all I/O using a blk_crypto_key has completed, filesystems can call
blk_crypto_evict_key(). However, the block layer currently doesn't call
blk_crypto_put_keyslot() until the request is being freed, which happens
after upper layers have been told (via bio_endio()) the I/O has
completed. This causes a race condition where blk_crypto_evict_key()
can see 'slot_refs != 0' without there being an actual bug.
This makes __blk_crypto_evict_key() hit the
'WARN_ON_ONCE(atomic_read(&slot->slot_refs) != 0)' and return without
doing anything, eventually causing a use-after-free in
blk_crypto_reprogram_all_keys(). (This is a very rare bug and has only
been seen when per-file keys are being used with fscrypt.)
There are two options to fix this: either release the keyslot before
bio_endio() is called on the request's last bio, or make
__blk_crypto_evict_key() ignore slot_refs. Let's go with the first
solution, since it preserves the ability to report bugs (via
WARN_ON_ONCE) where a key is evicted while still in-use. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/irdma: Cap MSIX used to online CPUs + 1
The irdma driver can use a maximum number of msix vectors equal
to num_online_cpus() + 1 and the kernel warning stack below is shown
if that number is exceeded.
The kernel throws a warning as the driver tries to update the affinity
hint with a CPU mask greater than the max CPU IDs. Fix this by capping
the MSIX vectors to num_online_cpus() + 1.
WARNING: CPU: 7 PID: 23655 at include/linux/cpumask.h:106 irdma_cfg_ceq_vector+0x34c/0x3f0 [irdma]
RIP: 0010:irdma_cfg_ceq_vector+0x34c/0x3f0 [irdma]
Call Trace:
irdma_rt_init_hw+0xa62/0x1290 [irdma]
? irdma_alloc_local_mac_entry+0x1a0/0x1a0 [irdma]
? __is_kernel_percpu_address+0x63/0x310
? rcu_read_lock_held_common+0xe/0xb0
? irdma_lan_unregister_qset+0x280/0x280 [irdma]
? irdma_request_reset+0x80/0x80 [irdma]
? ice_get_qos_params+0x84/0x390 [ice]
irdma_probe+0xa40/0xfc0 [irdma]
? rcu_read_lock_bh_held+0xd0/0xd0
? irdma_remove+0x140/0x140 [irdma]
? rcu_read_lock_sched_held+0x62/0xe0
? down_write+0x187/0x3d0
? auxiliary_match_id+0xf0/0x1a0
? irdma_remove+0x140/0x140 [irdma]
auxiliary_bus_probe+0xa6/0x100
__driver_probe_device+0x4a4/0xd50
? __device_attach_driver+0x2c0/0x2c0
driver_probe_device+0x4a/0x110
__driver_attach+0x1aa/0x350
bus_for_each_dev+0x11d/0x1b0
? subsys_dev_iter_init+0xe0/0xe0
bus_add_driver+0x3b1/0x610
driver_register+0x18e/0x410
? 0xffffffffc0b88000
irdma_init_module+0x50/0xaa [irdma]
do_one_initcall+0x103/0x5f0
? perf_trace_initcall_level+0x420/0x420
? do_init_module+0x4e/0x700
? __kasan_kmalloc+0x7d/0xa0
? kmem_cache_alloc_trace+0x188/0x2b0
? kasan_unpoison+0x21/0x50
do_init_module+0x1d1/0x700
load_module+0x3867/0x5260
? layout_and_allocate+0x3990/0x3990
? rcu_read_lock_held_common+0xe/0xb0
? rcu_read_lock_sched_held+0x62/0xe0
? rcu_read_lock_bh_held+0xd0/0xd0
? __vmalloc_node_range+0x46b/0x890
? lock_release+0x5c8/0xba0
? alloc_vm_area+0x120/0x120
? selinux_kernel_module_from_file+0x2a5/0x300
? __inode_security_revalidate+0xf0/0xf0
? __do_sys_init_module+0x1db/0x260
__do_sys_init_module+0x1db/0x260
? load_module+0x5260/0x5260
? do_syscall_64+0x22/0x450
do_syscall_64+0xa5/0x450
entry_SYSCALL_64_after_hwframe+0x66/0xdb |
| In the Linux kernel, the following vulnerability has been resolved:
media: mediatek: vcodec: fix decoder disable pm crash
Can't call pm_runtime_disable when the architecture support sub device for
'dev->pm.dev' is NUll, or will get below crash log.
[ 10.771551] pc : _raw_spin_lock_irq+0x4c/0xa0
[ 10.771556] lr : __pm_runtime_disable+0x30/0x130
[ 10.771558] sp : ffffffc01e4cb800
[ 10.771559] x29: ffffffc01e4cb800 x28: ffffffdf082108a8
[ 10.771563] x27: ffffffc01e4cbd70 x26: ffffff8605df55f0
[ 10.771567] x25: 0000000000000002 x24: 0000000000000002
[ 10.771570] x23: ffffff85c0dc9c00 x22: 0000000000000001
[ 10.771573] x21: 0000000000000001 x20: 0000000000000000
[ 10.771577] x19: 00000000000000f4 x18: ffffffdf2e9fbe18
[ 10.771580] x17: 0000000000000000 x16: ffffffdf2df13c74
[ 10.771583] x15: 00000000000002ea x14: 0000000000000058
[ 10.771587] x13: ffffffdf2de1b62c x12: ffffffdf2e9e30e4
[ 10.771590] x11: 0000000000000000 x10: 0000000000000001
[ 10.771593] x9 : 0000000000000000 x8 : 00000000000000f4
[ 10.771596] x7 : 6bff6264632c6264 x6 : 0000000000008000
[ 10.771600] x5 : 0080000000000000 x4 : 0000000000000001
[ 10.771603] x3 : 0000000000000008 x2 : 0000000000000001
[ 10.771608] x1 : 0000000000000000 x0 : 00000000000000f4
[ 10.771613] Call trace:
[ 10.771617] _raw_spin_lock_irq+0x4c/0xa0
[ 10.771620] __pm_runtime_disable+0x30/0x130
[ 10.771657] mtk_vcodec_probe+0x69c/0x728 [mtk_vcodec_dec 800cc929d6631f79f9b273254c8db94d0d3500dc]
[ 10.771662] platform_drv_probe+0x9c/0xbc
[ 10.771665] really_probe+0x13c/0x3a0
[ 10.771668] driver_probe_device+0x84/0xc0
[ 10.771671] device_driver_attach+0x54/0x78 |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix rbtree traversal bug in ext4_mb_use_preallocated
During allocations, while looking for preallocations(PA) in the per
inode rbtree, we can't do a direct traversal of the tree because
ext4_mb_discard_group_preallocation() can paralelly mark the pa deleted
and that can cause direct traversal to skip some entries. This was
leading to a BUG_ON() being hit [1] when we missed a PA that could satisfy
our request and ultimately tried to create a new PA that would overlap
with the missed one.
To makes sure we handle that case while still keeping the performance of
the rbtree, we make use of the fact that the only pa that could possibly
overlap the original goal start is the one that satisfies the below
conditions:
1. It must have it's logical start immediately to the left of
(ie less than) original logical start.
2. It must not be deleted
To find this pa we use the following traversal method:
1. Descend into the rbtree normally to find the immediate neighboring
PA. Here we keep descending irrespective of if the PA is deleted or if
it overlaps with our request etc. The goal is to find an immediately
adjacent PA.
2. If the found PA is on right of original goal, use rb_prev() to find
the left adjacent PA.
3. Check if this PA is deleted and keep moving left with rb_prev() until
a non deleted PA is found.
4. This is the PA we are looking for. Now we can check if it can satisfy
the original request and proceed accordingly.
This approach also takes care of having deleted PAs in the tree.
(While we are at it, also fix a possible overflow bug in calculating the
end of a PA)
[1] https://lore.kernel.org/linux-ext4/CA+G9fYv2FRpLqBZf34ZinR8bU2_ZRAUOjKAD3+tKRFaEQHtt8Q@mail.gmail.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
PCI: Fix dropping valid root bus resources with .end = zero
On r8a7791/koelsch:
kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
# cat /sys/kernel/debug/kmemleak
unreferenced object 0xc3a34e00 (size 64):
comm "swapper/0", pid 1, jiffies 4294937460 (age 199.080s)
hex dump (first 32 bytes):
b4 5d 81 f0 b4 5d 81 f0 c0 b0 a2 c3 00 00 00 00 .]...]..........
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<fe3aa979>] __kmalloc+0xf0/0x140
[<34bd6bc0>] resource_list_create_entry+0x18/0x38
[<767046bc>] pci_add_resource_offset+0x20/0x68
[<b3f3edf2>] devm_of_pci_get_host_bridge_resources.constprop.0+0xb0/0x390
When coalescing two resources for a contiguous aperture, the second
resource is enlarged to cover the full contiguous range, while the first
resource is marked invalid. This invalidation is done by clearing the
flags, start, and end members.
When adding the initial resources to the bus later, invalid resources are
skipped. Unfortunately, the check for an invalid resource considers only
the end member, causing false positives.
E.g. on r8a7791/koelsch, root bus resource 0 ("bus 00") is skipped, and no
longer registered with pci_bus_insert_busn_res() (causing the memory leak),
nor printed:
pci-rcar-gen2 ee090000.pci: host bridge /soc/pci@ee090000 ranges:
pci-rcar-gen2 ee090000.pci: MEM 0x00ee080000..0x00ee08ffff -> 0x00ee080000
pci-rcar-gen2 ee090000.pci: PCI: revision 11
pci-rcar-gen2 ee090000.pci: PCI host bridge to bus 0000:00
-pci_bus 0000:00: root bus resource [bus 00]
pci_bus 0000:00: root bus resource [mem 0xee080000-0xee08ffff]
Fix this by only skipping resources where all of the flags, start, and end
members are zero. |
| In the Linux kernel, the following vulnerability has been resolved:
posix-timers: Prevent RT livelock in itimer_delete()
itimer_delete() has a retry loop when the timer is concurrently expired. On
non-RT kernels this just spin-waits until the timer callback has completed,
except for posix CPU timers which have HAVE_POSIX_CPU_TIMERS_TASK_WORK
enabled.
In that case and on RT kernels the existing task could live lock when
preempting the task which does the timer delivery.
Replace spin_unlock() with an invocation of timer_wait_running() to handle
it the same way as the other retry loops in the posix timer code. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: fix potential kgd_mem UAFs
kgd_mem pointers returned by kfd_process_device_translate_handle are
only guaranteed to be valid while p->mutex is held. As soon as the mutex
is unlocked, another thread can free the BO. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: lib/mpi - avoid null pointer deref in mpi_cmp_ui()
During NVMeTCP Authentication a controller can trigger a kernel
oops by specifying the 8192 bit Diffie Hellman group and passing
a correctly sized, but zeroed Diffie Hellamn value.
mpi_cmp_ui() was detecting this if the second parameter was 0,
but 1 is passed from dh_is_pubkey_valid(). This causes the null
pointer u->d to be dereferenced towards the end of mpi_cmp_ui() |
| In the Linux kernel, the following vulnerability has been resolved:
ARM: zynq: Fix refcount leak in zynq_early_slcr_init
of_find_compatible_node() returns a node pointer with refcount incremented,
we should use of_node_put() on error path.
Add missing of_node_put() to avoid refcount leak. |
| In the Linux kernel, the following vulnerability has been resolved:
loop: loop_set_status_from_info() check before assignment
In loop_set_status_from_info(), lo->lo_offset and lo->lo_sizelimit should
be checked before reassignment, because if an overflow error occurs, the
original correct value will be changed to the wrong value, and it will not
be changed back.
More, the original patch did not solve the problem, the value was set and
ioctl returned an error, but the subsequent io used the value in the loop
driver, which still caused an alarm:
loop_handle_cmd
do_req_filebacked
loff_t pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
lo_rw_aio
cmd->iocb.ki_pos = pos |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: Ignore frags from uninitialized peer in dp.
When max virtual ap interfaces are configured in all the bands with
ACS and hostapd restart is done every 60s, a crash is observed at
random times.
In this certain scenario, a fragmented packet is received for
self peer, for which rx_tid and rx_frags are not initialized in
datapath. While handling this fragment, crash is observed as the
rx_frag list is uninitialised and when we walk in
ath11k_dp_rx_h_sort_frags, skb null leads to exception.
To address this, before processing received fragments we check
dp_setup_done flag is set to ensure that peer has completed its
dp peer setup for fragment queue, else ignore processing the
fragments.
Call trace:
ath11k_dp_process_rx_err+0x550/0x1084 [ath11k]
ath11k_dp_service_srng+0x70/0x370 [ath11k]
0xffffffc009693a04
__napi_poll+0x30/0xa4
net_rx_action+0x118/0x270
__do_softirq+0x10c/0x244
irq_exit+0x64/0xb4
__handle_domain_irq+0x88/0xac
gic_handle_irq+0x74/0xbc
el1_irq+0xf0/0x1c0
arch_cpu_idle+0x10/0x18
do_idle+0x104/0x248
cpu_startup_entry+0x20/0x64
rest_init+0xd0/0xdc
arch_call_rest_init+0xc/0x14
start_kernel+0x480/0x4b8
Code: f9400281 f94066a2 91405021 b94a0023 (f9406401)
Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.7.0.1-01744-QCAHKSWPL_SILICONZ-1 |
| In the Linux kernel, the following vulnerability has been resolved:
block/rq_qos: protect rq_qos apis with a new lock
commit 50e34d78815e ("block: disable the elevator int del_gendisk")
move rq_qos_exit() from disk_release() to del_gendisk(), this will
introduce some problems:
1) If rq_qos_add() is triggered by enabling iocost/iolatency through
cgroupfs, then it can concurrent with del_gendisk(), it's not safe to
write 'q->rq_qos' concurrently.
2) Activate cgroup policy that is relied on rq_qos will call
rq_qos_add() and blkcg_activate_policy(), and if rq_qos_exit() is
called in the middle, null-ptr-dereference will be triggered in
blkcg_activate_policy().
3) blkg_conf_open_bdev() can call blkdev_get_no_open() first to find the
disk, then if rq_qos_exit() from del_gendisk() is done before
rq_qos_add(), then memory will be leaked.
This patch add a new disk level mutex 'rq_qos_mutex':
1) The lock will protect rq_qos_exit() directly.
2) For wbt that doesn't relied on blk-cgroup, rq_qos_add() can only be
called from disk initialization for now because wbt can't be
destructed until rq_qos_exit(), so it's safe not to protect wbt for
now. Hoever, in case that rq_qos dynamically destruction is supported
in the furture, this patch also protect rq_qos_add() from wbt_init()
directly, this is enough because blk-sysfs already synchronize
writers with disk removal.
3) For iocost and iolatency, in order to synchronize disk removal and
cgroup configuration, the lock is held after blkdev_get_no_open()
from blkg_conf_open_bdev(), and is released in blkg_conf_exit().
In order to fix the above memory leak, disk_live() is checked after
holding the new lock. |
