| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix DMA-API call trace on NVMe LS requests
The following message and call trace was seen with debug kernels:
DMA-API: qla2xxx 0000:41:00.0: device driver failed to check map
error [device address=0x00000002a3ff38d8] [size=1024 bytes] [mapped as
single]
WARNING: CPU: 0 PID: 2930 at kernel/dma/debug.c:1017
check_unmap+0xf42/0x1990
Call Trace:
debug_dma_unmap_page+0xc9/0x100
qla_nvme_ls_unmap+0x141/0x210 [qla2xxx]
Remove DMA mapping from the driver altogether, as it is already done by FC
layer. This prevents the warning. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: rndis_host: Secure rndis_query check against int overflow
Variables off and len typed as uint32 in rndis_query function
are controlled by incoming RNDIS response message thus their
value may be manipulated. Setting off to a unexpectetly large
value will cause the sum with len and 8 to overflow and pass
the implemented validation step. Consequently the response
pointer will be referring to a location past the expected
buffer boundaries allowing information leakage e.g. via
RNDIS_OID_802_3_PERMANENT_ADDRESS OID. |
| In the Linux kernel, the following vulnerability has been resolved:
kcm: Fix memory leak in error path of kcm_sendmsg()
syzbot reported a memory leak like below:
BUG: memory leak
unreferenced object 0xffff88810b088c00 (size 240):
comm "syz-executor186", pid 5012, jiffies 4294943306 (age 13.680s)
hex dump (first 32 bytes):
00 89 08 0b 81 88 ff ff 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff83e5d5ff>] __alloc_skb+0x1ef/0x230 net/core/skbuff.c:634
[<ffffffff84606e59>] alloc_skb include/linux/skbuff.h:1289 [inline]
[<ffffffff84606e59>] kcm_sendmsg+0x269/0x1050 net/kcm/kcmsock.c:815
[<ffffffff83e479c6>] sock_sendmsg_nosec net/socket.c:725 [inline]
[<ffffffff83e479c6>] sock_sendmsg+0x56/0xb0 net/socket.c:748
[<ffffffff83e47f55>] ____sys_sendmsg+0x365/0x470 net/socket.c:2494
[<ffffffff83e4c389>] ___sys_sendmsg+0xc9/0x130 net/socket.c:2548
[<ffffffff83e4c536>] __sys_sendmsg+0xa6/0x120 net/socket.c:2577
[<ffffffff84ad7bb8>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff84ad7bb8>] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
[<ffffffff84c0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
In kcm_sendmsg(), kcm_tx_msg(head)->last_skb is used as a cursor to append
newly allocated skbs to 'head'. If some bytes are copied, an error occurred,
and jumped to out_error label, 'last_skb' is left unmodified. A later
kcm_sendmsg() will use an obsoleted 'last_skb' reference, corrupting the
'head' frag_list and causing the leak.
This patch fixes this issue by properly updating the last allocated skb in
'last_skb'. |
| In the Linux kernel, the following vulnerability has been resolved:
net: nsh: Use correct mac_offset to unwind gso skb in nsh_gso_segment()
As the call trace shows, skb_panic was caused by wrong skb->mac_header
in nsh_gso_segment():
invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 3 PID: 2737 Comm: syz Not tainted 6.3.0-next-20230505 #1
RIP: 0010:skb_panic+0xda/0xe0
call Trace:
skb_push+0x91/0xa0
nsh_gso_segment+0x4f3/0x570
skb_mac_gso_segment+0x19e/0x270
__skb_gso_segment+0x1e8/0x3c0
validate_xmit_skb+0x452/0x890
validate_xmit_skb_list+0x99/0xd0
sch_direct_xmit+0x294/0x7c0
__dev_queue_xmit+0x16f0/0x1d70
packet_xmit+0x185/0x210
packet_snd+0xc15/0x1170
packet_sendmsg+0x7b/0xa0
sock_sendmsg+0x14f/0x160
The root cause is:
nsh_gso_segment() use skb->network_header - nhoff to reset mac_header
in skb_gso_error_unwind() if inner-layer protocol gso fails.
However, skb->network_header may be reset by inner-layer protocol
gso function e.g. mpls_gso_segment. skb->mac_header reset by the
inaccurate network_header will be larger than skb headroom.
nsh_gso_segment
nhoff = skb->network_header - skb->mac_header;
__skb_pull(skb,nsh_len)
skb_mac_gso_segment
mpls_gso_segment
skb_reset_network_header(skb);//skb->network_header+=nsh_len
return -EINVAL;
skb_gso_error_unwind
skb_push(skb, nsh_len);
skb->mac_header = skb->network_header - nhoff;
// skb->mac_header > skb->headroom, cause skb_push panic
Use correct mac_offset to restore mac_header and get rid of nhoff. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/dcssblk: fix kernel crash with list_add corruption
Commit fb08a1908cb1 ("dax: simplify the dax_device <-> gendisk
association") introduced new logic for gendisk association, requiring
drivers to explicitly call dax_add_host() and dax_remove_host().
For dcssblk driver, some dax_remove_host() calls were missing, e.g. in
device remove path. The commit also broke error handling for out_dax case
in device add path, resulting in an extra put_device() w/o the previous
get_device() in that case.
This lead to stale xarray entries after device add / remove cycles. In the
case when a previously used struct gendisk pointer (xarray index) would be
used again, because blk_alloc_disk() happened to return such a pointer, the
xa_insert() in dax_add_host() would fail and go to out_dax, doing the extra
put_device() in the error path. In combination with an already flawed error
handling in dcssblk (device_register() cleanup), which needs to be
addressed in a separate patch, this resulted in a missing device_del() /
klist_del(), and eventually in the kernel crash with list_add corruption on
a subsequent device_add() / klist_add().
Fix this by adding the missing dax_remove_host() calls, and also move the
put_device() in the error path to restore the previous logic. |
| In the Linux kernel, the following vulnerability has been resolved:
inotify: Avoid reporting event with invalid wd
When inotify_freeing_mark() races with inotify_handle_inode_event() it
can happen that inotify_handle_inode_event() sees that i_mark->wd got
already reset to -1 and reports this value to userspace which can
confuse the inotify listener. Avoid the problem by validating that wd is
sensible (and pretend the mark got removed before the event got
generated otherwise). |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: safexcel - Cleanup ring IRQ workqueues on load failure
A failure loading the safexcel driver results in the following warning
on boot, because the IRQ affinity has not been correctly cleaned up.
Ensure we clean up the affinity and workqueues on a failure to load the
driver.
crypto-safexcel: probe of f2800000.crypto failed with error -2
------------[ cut here ]------------
WARNING: CPU: 1 PID: 232 at kernel/irq/manage.c:1913 free_irq+0x300/0x340
Modules linked in: hwmon mdio_i2c crypto_safexcel(+) md5 sha256_generic libsha256 authenc libdes omap_rng rng_core nft_masq nft_nat nft_chain_nat nf_nat nft_ct nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables libcrc32c nfnetlink fuse autofs4
CPU: 1 PID: 232 Comm: systemd-udevd Tainted: G W 6.1.6-00002-g9d4898824677 #3
Hardware name: MikroTik RB5009 (DT)
pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : free_irq+0x300/0x340
lr : free_irq+0x2e0/0x340
sp : ffff800008fa3890
x29: ffff800008fa3890 x28: 0000000000000000 x27: 0000000000000000
x26: ffff8000008e6dc0 x25: ffff000009034cac x24: ffff000009034d50
x23: 0000000000000000 x22: 000000000000004a x21: ffff0000093e0d80
x20: ffff000009034c00 x19: ffff00000615fc00 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 000075f5c1584c5e
x14: 0000000000000017 x13: 0000000000000000 x12: 0000000000000040
x11: ffff000000579b60 x10: ffff000000579b62 x9 : ffff800008bbe370
x8 : ffff000000579dd0 x7 : 0000000000000000 x6 : ffff000000579e18
x5 : ffff000000579da8 x4 : ffff800008ca0000 x3 : ffff800008ca0188
x2 : 0000000013033204 x1 : ffff000009034c00 x0 : ffff8000087eadf0
Call trace:
free_irq+0x300/0x340
devm_irq_release+0x14/0x20
devres_release_all+0xa0/0x100
device_unbind_cleanup+0x14/0x60
really_probe+0x198/0x2d4
__driver_probe_device+0x74/0xdc
driver_probe_device+0x3c/0x110
__driver_attach+0x8c/0x190
bus_for_each_dev+0x6c/0xc0
driver_attach+0x20/0x30
bus_add_driver+0x148/0x1fc
driver_register+0x74/0x120
__platform_driver_register+0x24/0x30
safexcel_init+0x48/0x1000 [crypto_safexcel]
do_one_initcall+0x4c/0x1b0
do_init_module+0x44/0x1cc
load_module+0x1724/0x1be4
__do_sys_finit_module+0xbc/0x110
__arm64_sys_finit_module+0x1c/0x24
invoke_syscall+0x44/0x110
el0_svc_common.constprop.0+0xc0/0xe0
do_el0_svc+0x20/0x80
el0_svc+0x14/0x4c
el0t_64_sync_handler+0xb0/0xb4
el0t_64_sync+0x148/0x14c
---[ end trace 0000000000000000 ]--- |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: rt2x00: Fix memory leak when handling surveys
When removing a rt2x00 device, its associated channel surveys
are not freed, causing a memory leak observable with kmemleak:
unreferenced object 0xffff9620f0881a00 (size 512):
comm "systemd-udevd", pid 2290, jiffies 4294906974 (age 33.768s)
hex dump (first 32 bytes):
70 44 12 00 00 00 00 00 92 8a 00 00 00 00 00 00 pD..............
00 00 00 00 00 00 00 00 ab 87 01 00 00 00 00 00 ................
backtrace:
[<ffffffffb0ed858b>] __kmalloc+0x4b/0x130
[<ffffffffc1b0f29b>] rt2800_probe_hw+0xc2b/0x1380 [rt2800lib]
[<ffffffffc1a9496e>] rt2800usb_probe_hw+0xe/0x60 [rt2800usb]
[<ffffffffc1ae491a>] rt2x00lib_probe_dev+0x21a/0x7d0 [rt2x00lib]
[<ffffffffc1b3b83e>] rt2x00usb_probe+0x1be/0x980 [rt2x00usb]
[<ffffffffc05981e2>] usb_probe_interface+0xe2/0x310 [usbcore]
[<ffffffffb13be2d5>] really_probe+0x1a5/0x410
[<ffffffffb13be5c8>] __driver_probe_device+0x78/0x180
[<ffffffffb13be6fe>] driver_probe_device+0x1e/0x90
[<ffffffffb13be972>] __driver_attach+0xd2/0x1c0
[<ffffffffb13bbc57>] bus_for_each_dev+0x77/0xd0
[<ffffffffb13bd2a2>] bus_add_driver+0x112/0x210
[<ffffffffb13bfc6c>] driver_register+0x5c/0x120
[<ffffffffc0596ae8>] usb_register_driver+0x88/0x150 [usbcore]
[<ffffffffb0c011c4>] do_one_initcall+0x44/0x220
[<ffffffffb0d6134c>] do_init_module+0x4c/0x220
Fix this by freeing the channel surveys on device removal.
Tested with a RT3070 based USB wireless adapter. |
| In the Linux kernel, the following vulnerability has been resolved:
vfio/type1: fix cap_migration information leak
Fix an information leak where an uninitialized hole in struct
vfio_iommu_type1_info_cap_migration on the stack is exposed to userspace.
The definition of struct vfio_iommu_type1_info_cap_migration contains a hole as
shown in this pahole(1) output:
struct vfio_iommu_type1_info_cap_migration {
struct vfio_info_cap_header header; /* 0 8 */
__u32 flags; /* 8 4 */
/* XXX 4 bytes hole, try to pack */
__u64 pgsize_bitmap; /* 16 8 */
__u64 max_dirty_bitmap_size; /* 24 8 */
/* size: 32, cachelines: 1, members: 4 */
/* sum members: 28, holes: 1, sum holes: 4 */
/* last cacheline: 32 bytes */
};
The cap_mig variable is filled in without initializing the hole:
static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
struct vfio_info_cap *caps)
{
struct vfio_iommu_type1_info_cap_migration cap_mig;
cap_mig.header.id = VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION;
cap_mig.header.version = 1;
cap_mig.flags = 0;
/* support minimum pgsize */
cap_mig.pgsize_bitmap = (size_t)1 << __ffs(iommu->pgsize_bitmap);
cap_mig.max_dirty_bitmap_size = DIRTY_BITMAP_SIZE_MAX;
return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig));
}
The structure is then copied to a temporary location on the heap. At this point
it's already too late and ioctl(VFIO_IOMMU_GET_INFO) copies it to userspace
later:
int vfio_info_add_capability(struct vfio_info_cap *caps,
struct vfio_info_cap_header *cap, size_t size)
{
struct vfio_info_cap_header *header;
header = vfio_info_cap_add(caps, size, cap->id, cap->version);
if (IS_ERR(header))
return PTR_ERR(header);
memcpy(header + 1, cap + 1, size - sizeof(*header));
return 0;
}
This issue was found by code inspection. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Fix kernel warning during topology setup
This patch fixes the following kernel warning seen during
driver load by correctly initializing the p2plink attr before
creating the sysfs file:
[ +0.002865] ------------[ cut here ]------------
[ +0.002327] kobject: '(null)' (0000000056260cfb): is not initialized, yet kobject_put() is being called.
[ +0.004780] WARNING: CPU: 32 PID: 1006 at lib/kobject.c:718 kobject_put+0xaa/0x1c0
[ +0.001361] Call Trace:
[ +0.001234] <TASK>
[ +0.001067] kfd_remove_sysfs_node_entry+0x24a/0x2d0 [amdgpu]
[ +0.003147] kfd_topology_update_sysfs+0x3d/0x750 [amdgpu]
[ +0.002890] kfd_topology_add_device+0xbd7/0xc70 [amdgpu]
[ +0.002844] ? lock_release+0x13c/0x2e0
[ +0.001936] ? smu_cmn_send_smc_msg_with_param+0x1e8/0x2d0 [amdgpu]
[ +0.003313] ? amdgpu_dpm_get_mclk+0x54/0x60 [amdgpu]
[ +0.002703] kgd2kfd_device_init.cold+0x39f/0x4ed [amdgpu]
[ +0.002930] amdgpu_amdkfd_device_init+0x13d/0x1f0 [amdgpu]
[ +0.002944] amdgpu_device_init.cold+0x1464/0x17b4 [amdgpu]
[ +0.002970] ? pci_bus_read_config_word+0x43/0x80
[ +0.002380] amdgpu_driver_load_kms+0x15/0x100 [amdgpu]
[ +0.002744] amdgpu_pci_probe+0x147/0x370 [amdgpu]
[ +0.002522] local_pci_probe+0x40/0x80
[ +0.001896] work_for_cpu_fn+0x10/0x20
[ +0.001892] process_one_work+0x26e/0x5a0
[ +0.002029] worker_thread+0x1fd/0x3e0
[ +0.001890] ? process_one_work+0x5a0/0x5a0
[ +0.002115] kthread+0xea/0x110
[ +0.001618] ? kthread_complete_and_exit+0x20/0x20
[ +0.002422] ret_from_fork+0x1f/0x30
[ +0.001808] </TASK>
[ +0.001103] irq event stamp: 59837
[ +0.001718] hardirqs last enabled at (59849): [<ffffffffb30fab12>] __up_console_sem+0x52/0x60
[ +0.004414] hardirqs last disabled at (59860): [<ffffffffb30faaf7>] __up_console_sem+0x37/0x60
[ +0.004414] softirqs last enabled at (59654): [<ffffffffb307d9c7>] irq_exit_rcu+0xd7/0x130
[ +0.004205] softirqs last disabled at (59649): [<ffffffffb307d9c7>] irq_exit_rcu+0xd7/0x130
[ +0.004203] ---[ end trace 0000000000000000 ]--- |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: drop unnecessary user-triggerable WARN_ONCE in verifierl log
It's trivial for user to trigger "verifier log line truncated" warning,
as verifier has a fixed-sized buffer of 1024 bytes (as of now), and there are at
least two pieces of user-provided information that can be output through
this buffer, and both can be arbitrarily sized by user:
- BTF names;
- BTF.ext source code lines strings.
Verifier log buffer should be properly sized for typical verifier state
output. But it's sort-of expected that this buffer won't be long enough
in some circumstances. So let's drop the check. In any case code will
work correctly, at worst truncating a part of a single line output. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd: Fix an out of bounds error in BIOS parser
The array is hardcoded to 8 in atomfirmware.h, but firmware provides
a bigger one sometimes. Deferencing the larger array causes an out
of bounds error.
commit 4fc1ba4aa589 ("drm/amd/display: fix array index out of bound error
in bios parser") fixed some of this, but there are two other cases
not covered by it. Fix those as well. |
| In the Linux kernel, the following vulnerability has been resolved:
net: core: remove unnecessary frame_sz check in bpf_xdp_adjust_tail()
Syzkaller reported the following issue:
=======================================
Too BIG xdp->frame_sz = 131072
WARNING: CPU: 0 PID: 5020 at net/core/filter.c:4121
____bpf_xdp_adjust_tail net/core/filter.c:4121 [inline]
WARNING: CPU: 0 PID: 5020 at net/core/filter.c:4121
bpf_xdp_adjust_tail+0x466/0xa10 net/core/filter.c:4103
...
Call Trace:
<TASK>
bpf_prog_4add87e5301a4105+0x1a/0x1c
__bpf_prog_run include/linux/filter.h:600 [inline]
bpf_prog_run_xdp include/linux/filter.h:775 [inline]
bpf_prog_run_generic_xdp+0x57e/0x11e0 net/core/dev.c:4721
netif_receive_generic_xdp net/core/dev.c:4807 [inline]
do_xdp_generic+0x35c/0x770 net/core/dev.c:4866
tun_get_user+0x2340/0x3ca0 drivers/net/tun.c:1919
tun_chr_write_iter+0xe8/0x210 drivers/net/tun.c:2043
call_write_iter include/linux/fs.h:1871 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x650/0xe40 fs/read_write.c:584
ksys_write+0x12f/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
xdp->frame_sz > PAGE_SIZE check was introduced in commit c8741e2bfe87
("xdp: Allow bpf_xdp_adjust_tail() to grow packet size"). But Jesper
Dangaard Brouer <jbrouer@redhat.com> noted that after introducing the
xdp_init_buff() which all XDP driver use - it's safe to remove this
check. The original intend was to catch cases where XDP drivers have
not been updated to use xdp.frame_sz, but that is not longer a concern
(since xdp_init_buff).
Running the initial syzkaller repro it was discovered that the
contiguous physical memory allocation is used for both xdp paths in
tun_get_user(), e.g. tun_build_skb() and tun_alloc_skb(). It was also
stated by Jesper Dangaard Brouer <jbrouer@redhat.com> that XDP can
work on higher order pages, as long as this is contiguous physical
memory (e.g. a page). |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: dice: fix buffer overflow in detect_stream_formats()
The function detect_stream_formats() reads the stream_count value directly
from a FireWire device without validating it. This can lead to
out-of-bounds writes when a malicious device provides a stream_count value
greater than MAX_STREAMS.
Fix by applying the same validation to both TX and RX stream counts in
detect_stream_formats(). |
| In the Linux kernel, the following vulnerability has been resolved:
can: hi311x: fix null pointer dereference when resuming from sleep before interface was enabled
This issue is similar to the vulnerability in the `mcp251x` driver,
which was fixed in commit 03c427147b2d ("can: mcp251x: fix resume from
sleep before interface was brought up").
In the `hi311x` driver, when the device resumes from sleep, the driver
schedules `priv->restart_work`. However, if the network interface was
not previously enabled, the `priv->wq` (workqueue) is not allocated and
initialized, leading to a null pointer dereference.
To fix this, we move the allocation and initialization of the workqueue
from the `hi3110_open` function to the `hi3110_can_probe` function.
This ensures that the workqueue is properly initialized before it is
used during device resume. And added logic to destroy the workqueue
in the error handling paths of `hi3110_can_probe` and in the
`hi3110_can_remove` function to prevent resource leaks. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: Fix peer lookup in ath12k_dp_mon_rx_deliver_msdu()
In ath12k_dp_mon_rx_deliver_msdu(), peer lookup fails because
rxcb->peer_id is not updated with a valid value. This is expected
in monitor mode, where RX frames bypass the regular RX
descriptor path that typically sets rxcb->peer_id.
As a result, the peer is NULL, and link_id and link_valid fields
in the RX status are not populated. This leads to a WARN_ON in
mac80211 when it receives data frame from an associated station
with invalid link_id.
Fix this potential issue by using ppduinfo->peer_id, which holds
the correct peer id for the received frame. This ensures that the
peer is correctly found and the associated link metadata is updated
accordingly.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1 |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Free special fields when update [lru_,]percpu_hash maps
As [lru_,]percpu_hash maps support BPF_KPTR_{REF,PERCPU}, missing
calls to 'bpf_obj_free_fields()' in 'pcpu_copy_value()' could cause the
memory referenced by BPF_KPTR_{REF,PERCPU} fields to be held until the
map gets freed.
Fix this by calling 'bpf_obj_free_fields()' after
'copy_map_value[,_long]()' in 'pcpu_copy_value()'. |
| In the Linux kernel, the following vulnerability has been resolved:
comedi: fix divide-by-zero in comedi_buf_munge()
The comedi_buf_munge() function performs a modulo operation
`async->munge_chan %= async->cmd.chanlist_len` without first
checking if chanlist_len is zero. If a user program submits a command with
chanlist_len set to zero, this causes a divide-by-zero error when the device
processes data in the interrupt handler path.
Add a check for zero chanlist_len at the beginning of the
function, similar to the existing checks for !map and
CMDF_RAWDATA flag. When chanlist_len is zero, update
munge_count and return early, indicating the data was
handled without munging.
This prevents potential kernel panics from malformed user commands. |
| In the Linux kernel, the following vulnerability has been resolved:
block: Use RCU in blk_mq_[un]quiesce_tagset() instead of set->tag_list_lock
blk_mq_{add,del}_queue_tag_set() functions add and remove queues from
tagset, the functions make sure that tagset and queues are marked as
shared when two or more queues are attached to the same tagset.
Initially a tagset starts as unshared and when the number of added
queues reaches two, blk_mq_add_queue_tag_set() marks it as shared along
with all the queues attached to it. When the number of attached queues
drops to 1 blk_mq_del_queue_tag_set() need to mark both the tagset and
the remaining queues as unshared.
Both functions need to freeze current queues in tagset before setting on
unsetting BLK_MQ_F_TAG_QUEUE_SHARED flag. While doing so, both functions
hold set->tag_list_lock mutex, which makes sense as we do not want
queues to be added or deleted in the process. This used to work fine
until commit 98d81f0df70c ("nvme: use blk_mq_[un]quiesce_tagset")
made the nvme driver quiesce tagset instead of quiscing individual
queues. blk_mq_quiesce_tagset() does the job and quiesce the queues in
set->tag_list while holding set->tag_list_lock also.
This results in deadlock between two threads with these stacktraces:
__schedule+0x47c/0xbb0
? timerqueue_add+0x66/0xb0
schedule+0x1c/0xa0
schedule_preempt_disabled+0xa/0x10
__mutex_lock.constprop.0+0x271/0x600
blk_mq_quiesce_tagset+0x25/0xc0
nvme_dev_disable+0x9c/0x250
nvme_timeout+0x1fc/0x520
blk_mq_handle_expired+0x5c/0x90
bt_iter+0x7e/0x90
blk_mq_queue_tag_busy_iter+0x27e/0x550
? __blk_mq_complete_request_remote+0x10/0x10
? __blk_mq_complete_request_remote+0x10/0x10
? __call_rcu_common.constprop.0+0x1c0/0x210
blk_mq_timeout_work+0x12d/0x170
process_one_work+0x12e/0x2d0
worker_thread+0x288/0x3a0
? rescuer_thread+0x480/0x480
kthread+0xb8/0xe0
? kthread_park+0x80/0x80
ret_from_fork+0x2d/0x50
? kthread_park+0x80/0x80
ret_from_fork_asm+0x11/0x20
__schedule+0x47c/0xbb0
? xas_find+0x161/0x1a0
schedule+0x1c/0xa0
blk_mq_freeze_queue_wait+0x3d/0x70
? destroy_sched_domains_rcu+0x30/0x30
blk_mq_update_tag_set_shared+0x44/0x80
blk_mq_exit_queue+0x141/0x150
del_gendisk+0x25a/0x2d0
nvme_ns_remove+0xc9/0x170
nvme_remove_namespaces+0xc7/0x100
nvme_remove+0x62/0x150
pci_device_remove+0x23/0x60
device_release_driver_internal+0x159/0x200
unbind_store+0x99/0xa0
kernfs_fop_write_iter+0x112/0x1e0
vfs_write+0x2b1/0x3d0
ksys_write+0x4e/0xb0
do_syscall_64+0x5b/0x160
entry_SYSCALL_64_after_hwframe+0x4b/0x53
The top stacktrace is showing nvme_timeout() called to handle nvme
command timeout. timeout handler is trying to disable the controller and
as a first step, it needs to blk_mq_quiesce_tagset() to tell blk-mq not
to call queue callback handlers. The thread is stuck waiting for
set->tag_list_lock as it tries to walk the queues in set->tag_list.
The lock is held by the second thread in the bottom stack which is
waiting for one of queues to be frozen. The queue usage counter will
drop to zero after nvme_timeout() finishes, and this will not happen
because the thread will wait for this mutex forever.
Given that [un]quiescing queue is an operation that does not need to
sleep, update blk_mq_[un]quiesce_tagset() to use RCU instead of taking
set->tag_list_lock, update blk_mq_{add,del}_queue_tag_set() to use RCU
safe list operations. Also, delete INIT_LIST_HEAD(&q->tag_set_list)
in blk_mq_del_queue_tag_set() because we can not re-initialize it while
the list is being traversed under RCU. The deleted queue will not be
added/deleted to/from a tagset and it will be freed in blk_free_queue()
after the end of RCU grace period. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: dont report verifier bug for missing bpf_scc_visit on speculative path
Syzbot generated a program that triggers a verifier_bug() call in
maybe_exit_scc(). maybe_exit_scc() assumes that, when called for a
state with insn_idx in some SCC, there should be an instance of struct
bpf_scc_visit allocated for that SCC. Turns out the assumption does
not hold for speculative execution paths. See example in the next
patch.
maybe_scc_exit() is called from update_branch_counts() for states that
reach branch count of zero, meaning that path exploration for a
particular path is finished. Path exploration can finish in one of
three ways:
a. Verification error is found. In this case, update_branch_counts()
is called only for non-speculative paths.
b. Top level BPF_EXIT is reached. Such instructions are never a part of
an SCC, so compute_scc_callchain() in maybe_scc_exit() will return
false, and maybe_scc_exit() will return early.
c. A checkpoint is reached and matched. Checkpoints are created by
is_state_visited(), which calls maybe_enter_scc(), which allocates
bpf_scc_visit instances for checkpoints within SCCs.
Hence, for non-speculative symbolic execution paths, the assumption
still holds: if maybe_scc_exit() is called for a state within an SCC,
bpf_scc_visit instance must exist.
This patch removes the verifier_bug() call for speculative paths. |
