| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: mcast: extend RCU protection in igmp6_send()
igmp6_send() can be called without RTNL or RCU being held.
Extend RCU protection so that we can safely fetch the net pointer
and avoid a potential UAF.
Note that we no longer can use sock_alloc_send_skb() because
ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.
Instead use alloc_skb() and charge the net->ipv6.igmp_sk
socket under RCU protection. |
| In the Linux kernel, the following vulnerability has been resolved:
HID: hyperv: streamline driver probe to avoid devres issues
It was found that unloading 'hid_hyperv' module results in a devres
complaint:
...
hv_vmbus: unregistering driver hid_hyperv
------------[ cut here ]------------
WARNING: CPU: 2 PID: 3983 at drivers/base/devres.c:691 devres_release_group+0x1f2/0x2c0
...
Call Trace:
<TASK>
? devres_release_group+0x1f2/0x2c0
? __warn+0xd1/0x1c0
? devres_release_group+0x1f2/0x2c0
? report_bug+0x32a/0x3c0
? handle_bug+0x53/0xa0
? exc_invalid_op+0x18/0x50
? asm_exc_invalid_op+0x1a/0x20
? devres_release_group+0x1f2/0x2c0
? devres_release_group+0x90/0x2c0
? rcu_is_watching+0x15/0xb0
? __pfx_devres_release_group+0x10/0x10
hid_device_remove+0xf5/0x220
device_release_driver_internal+0x371/0x540
? klist_put+0xf3/0x170
bus_remove_device+0x1f1/0x3f0
device_del+0x33f/0x8c0
? __pfx_device_del+0x10/0x10
? cleanup_srcu_struct+0x337/0x500
hid_destroy_device+0xc8/0x130
mousevsc_remove+0xd2/0x1d0 [hid_hyperv]
device_release_driver_internal+0x371/0x540
driver_detach+0xc5/0x180
bus_remove_driver+0x11e/0x2a0
? __mutex_unlock_slowpath+0x160/0x5e0
vmbus_driver_unregister+0x62/0x2b0 [hv_vmbus]
...
And the issue seems to be that the corresponding devres group is not
allocated. Normally, devres_open_group() is called from
__hid_device_probe() but Hyper-V HID driver overrides 'hid_dev->driver'
with 'mousevsc_hid_driver' stub and basically re-implements
__hid_device_probe() by calling hid_parse() and hid_hw_start() but not
devres_open_group(). hid_device_probe() does not call __hid_device_probe()
for it. Later, when the driver is removed, hid_device_remove() calls
devres_release_group() as it doesn't check whether hdev->driver was
initially overridden or not.
The issue seems to be related to the commit 62c68e7cee33 ("HID: ensure
timely release of driver-allocated resources") but the commit itself seems
to be correct.
Fix the issue by dropping the 'hid_dev->driver' override and using
hid_register_driver()/hid_unregister_driver() instead. Alternatively, it
would have been possible to rely on the default handling but
HID_CONNECT_DEFAULT implies HID_CONNECT_HIDRAW and it doesn't seem to work
for mousevsc as-is. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/mediatek: Fix potential NULL dereference in mtk_crtc_destroy()
In mtk_crtc_create(), if the call to mbox_request_channel() fails then we
set the "mtk_crtc->cmdq_client.chan" pointer to NULL. In that situation,
we do not call cmdq_pkt_create().
During the cleanup, we need to check if the "mtk_crtc->cmdq_client.chan"
is NULL first before calling cmdq_pkt_destroy(). Calling
cmdq_pkt_destroy() is unnecessary if we didn't call cmdq_pkt_create() and
it will result in a NULL pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check null pointers before using them
[WHAT & HOW]
These pointers are null checked previously in the same function,
indicating they might be null as reported by Coverity. As a result,
they need to be checked when used again.
This fixes 3 FORWARD_NULL issue reported by Coverity. |
| In the Linux kernel, the following vulnerability has been resolved:
net/smc: check v2_ext_offset/eid_cnt/ism_gid_cnt when receiving proposal msg
When receiving proposal msg in server, the fields v2_ext_offset/
eid_cnt/ism_gid_cnt in proposal msg are from the remote client
and can not be fully trusted. Especially the field v2_ext_offset,
once exceed the max value, there has the chance to access wrong
address, and crash may happen.
This patch checks the fields v2_ext_offset/eid_cnt/ism_gid_cnt
before using them. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fail verification for sign-extension of packet data/data_end/data_meta
syzbot reported a kernel crash due to
commit 1f1e864b6555 ("bpf: Handle sign-extenstin ctx member accesses").
The reason is due to sign-extension of 32-bit load for
packet data/data_end/data_meta uapi field.
The original code looks like:
r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */
r3 = *(u32 *)(r1 + 80) /* load __sk_buff->data_end */
r0 = r2
r0 += 8
if r3 > r0 goto +1
...
Note that __sk_buff->data load has 32-bit sign extension.
After verification and convert_ctx_accesses(), the final asm code looks like:
r2 = *(u64 *)(r1 +208)
r2 = (s32)r2
r3 = *(u64 *)(r1 +80)
r0 = r2
r0 += 8
if r3 > r0 goto pc+1
...
Note that 'r2 = (s32)r2' may make the kernel __sk_buff->data address invalid
which may cause runtime failure.
Currently, in C code, typically we have
void *data = (void *)(long)skb->data;
void *data_end = (void *)(long)skb->data_end;
...
and it will generate
r2 = *(u64 *)(r1 +208)
r3 = *(u64 *)(r1 +80)
r0 = r2
r0 += 8
if r3 > r0 goto pc+1
If we allow sign-extension,
void *data = (void *)(long)(int)skb->data;
void *data_end = (void *)(long)skb->data_end;
...
the generated code looks like
r2 = *(u64 *)(r1 +208)
r2 <<= 32
r2 s>>= 32
r3 = *(u64 *)(r1 +80)
r0 = r2
r0 += 8
if r3 > r0 goto pc+1
and this will cause verification failure since "r2 <<= 32" is not allowed
as "r2" is a packet pointer.
To fix this issue for case
r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */
this patch added additional checking in is_valid_access() callback
function for packet data/data_end/data_meta access. If those accesses
are with sign-extenstion, the verification will fail.
[1] https://lore.kernel.org/bpf/000000000000c90eee061d236d37@google.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
net/smc: check smcd_v2_ext_offset when receiving proposal msg
When receiving proposal msg in server, the field smcd_v2_ext_offset in
proposal msg is from the remote client and can not be fully trusted.
Once the value of smcd_v2_ext_offset exceed the max value, there has
the chance to access wrong address, and crash may happen.
This patch checks the value of smcd_v2_ext_offset before using it. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Validate function returns
[WHAT & HOW]
Function return values must be checked before data can be used
in subsequent functions.
This fixes 4 CHECKED_RETURN issues reported by Coverity. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Ensure array index tg_inst won't be -1
[WHY & HOW]
tg_inst will be a negative if timing_generator_count equals 0, which
should be checked before used.
This fixes 2 OVERRUN issues reported by Coverity. |
| In the Linux kernel, the following vulnerability has been resolved:
net: mediatek: Fix potential NULL pointer dereference in dummy net_device handling
Move the freeing of the dummy net_device from mtk_free_dev() to
mtk_remove().
Previously, if alloc_netdev_dummy() failed in mtk_probe(),
eth->dummy_dev would be NULL. The error path would then call
mtk_free_dev(), which in turn called free_netdev() assuming dummy_dev
was allocated (but it was not), potentially causing a NULL pointer
dereference.
By moving free_netdev() to mtk_remove(), we ensure it's only called when
mtk_probe() has succeeded and dummy_dev is fully allocated. This
addresses a potential NULL pointer dereference detected by Smatch[1]. |
| In the Linux kernel, the following vulnerability has been resolved:
cxl/mem: Fix no cxl_nvd during pmem region auto-assembling
When CXL subsystem is auto-assembling a pmem region during cxl
endpoint port probing, always hit below calltrace.
BUG: kernel NULL pointer dereference, address: 0000000000000078
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
RIP: 0010:cxl_pmem_region_probe+0x22e/0x360 [cxl_pmem]
Call Trace:
<TASK>
? __die+0x24/0x70
? page_fault_oops+0x82/0x160
? do_user_addr_fault+0x65/0x6b0
? exc_page_fault+0x7d/0x170
? asm_exc_page_fault+0x26/0x30
? cxl_pmem_region_probe+0x22e/0x360 [cxl_pmem]
? cxl_pmem_region_probe+0x1ac/0x360 [cxl_pmem]
cxl_bus_probe+0x1b/0x60 [cxl_core]
really_probe+0x173/0x410
? __pfx___device_attach_driver+0x10/0x10
__driver_probe_device+0x80/0x170
driver_probe_device+0x1e/0x90
__device_attach_driver+0x90/0x120
bus_for_each_drv+0x84/0xe0
__device_attach+0xbc/0x1f0
bus_probe_device+0x90/0xa0
device_add+0x51c/0x710
devm_cxl_add_pmem_region+0x1b5/0x380 [cxl_core]
cxl_bus_probe+0x1b/0x60 [cxl_core]
The cxl_nvd of the memdev needs to be available during the pmem region
probe. Currently the cxl_nvd is registered after the endpoint port probe.
The endpoint probe, in the case of autoassembly of regions, can cause a
pmem region probe requiring the not yet available cxl_nvd. Adjust the
sequence so this dependency is met.
This requires adding a port parameter to cxl_find_nvdimm_bridge() that
can be used to query the ancestor root port. The endpoint port is not
yet available, but will share a common ancestor with its parent, so
start the query from there instead. |
| In the Linux kernel, the following vulnerability has been resolved:
nvme-fabrics: use reserved tag for reg read/write command
In some scenarios, if too many commands are issued by nvme command in
the same time by user tasks, this may exhaust all tags of admin_q. If
a reset (nvme reset or IO timeout) occurs before these commands finish,
reconnect routine may fail to update nvme regs due to insufficient tags,
which will cause kernel hang forever. In order to workaround this issue,
maybe we can let reg_read32()/reg_read64()/reg_write32() use reserved
tags. This maybe safe for nvmf:
1. For the disable ctrl path, we will not issue connect command
2. For the enable ctrl / fw activate path, since connect and reg_xx()
are called serially.
So the reserved tags may still be enough while reg_xx() use reserved tags. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Defer work in bpf_timer_cancel_and_free
Currently, the same case as previous patch (two timer callbacks trying
to cancel each other) can be invoked through bpf_map_update_elem as
well, or more precisely, freeing map elements containing timers. Since
this relies on hrtimer_cancel as well, it is prone to the same deadlock
situation as the previous patch.
It would be sufficient to use hrtimer_try_to_cancel to fix this problem,
as the timer cannot be enqueued after async_cancel_and_free. Once
async_cancel_and_free has been done, the timer must be reinitialized
before it can be armed again. The callback running in parallel trying to
arm the timer will fail, and freeing bpf_hrtimer without waiting is
sufficient (given kfree_rcu), and bpf_timer_cb will return
HRTIMER_NORESTART, preventing the timer from being rearmed again.
However, there exists a UAF scenario where the callback arms the timer
before entering this function, such that if cancellation fails (due to
timer callback invoking this routine, or the target timer callback
running concurrently). In such a case, if the timer expiration is
significantly far in the future, the RCU grace period expiration
happening before it will free the bpf_hrtimer state and along with it
the struct hrtimer, that is enqueued.
Hence, it is clear cancellation needs to occur after
async_cancel_and_free, and yet it cannot be done inline due to deadlock
issues. We thus modify bpf_timer_cancel_and_free to defer work to the
global workqueue, adding a work_struct alongside rcu_head (both used at
_different_ points of time, so can share space).
Update existing code comments to reflect the new state of affairs. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: fix kernel crash during resume
Currently during resume, QMI target memory is not properly handled, resulting
in kernel crash in case DMA remap is not supported:
BUG: Bad page state in process kworker/u16:54 pfn:36e80
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x36e80
page dumped because: nonzero _refcount
Call Trace:
bad_page
free_page_is_bad_report
__free_pages_ok
__free_pages
dma_direct_free
dma_free_attrs
ath12k_qmi_free_target_mem_chunk
ath12k_qmi_msg_mem_request_cb
The reason is:
Once ath12k module is loaded, firmware sends memory request to host. In case
DMA remap not supported, ath12k refuses the first request due to failure in
allocating with large segment size:
ath12k_pci 0000:04:00.0: qmi firmware request memory request
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 7077888
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 8454144
ath12k_pci 0000:04:00.0: qmi dma allocation failed (7077888 B type 1), will try later with small size
ath12k_pci 0000:04:00.0: qmi delays mem_request 2
ath12k_pci 0000:04:00.0: qmi firmware request memory request
Later firmware comes back with more but small segments and allocation
succeeds:
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 262144
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288
ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 65536
ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288
Now ath12k is working. If suspend is triggered, firmware will be reloaded
during resume. As same as before, firmware requests two large segments at
first. In ath12k_qmi_msg_mem_request_cb() segment count and size are
assigned:
ab->qmi.mem_seg_count == 2
ab->qmi.target_mem[0].size == 7077888
ab->qmi.target_mem[1].size == 8454144
Then allocation failed like before and ath12k_qmi_free_target_mem_chunk()
is called to free all allocated segments. Note the first segment is skipped
because its v.addr is cleared due to allocation failure:
chunk->v.addr = dma_alloc_coherent()
Also note that this leaks that segment because it has not been freed.
While freeing the second segment, a size of 8454144 is passed to
dma_free_coherent(). However remember that this segment is allocated at
the first time firmware is loaded, before suspend. So its real size is
524288, much smaller than 8454144. As a result kernel found we are freeing
some memory which is in use and thus cras
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Add a dc_state NULL check in dc_state_release
[How]
Check wheather state is NULL before releasing it. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: SOF: avoid a NULL dereference with unsupported widgets
If an IPC4 topology contains an unsupported widget, its .module_info
field won't be set, then sof_ipc4_route_setup() will cause a kernel
Oops trying to dereference it. Add a check for such cases. |
| In the Linux kernel, the following vulnerability has been resolved:
blk-mq: fix tags leak when shrink nr_hw_queues
Although we don't need to realloc set->tags[] when shrink nr_hw_queues,
we need to free them. Or these tags will be leaked.
How to reproduce:
1. mount -t configfs configfs /mnt
2. modprobe null_blk nr_devices=0 submit_queues=8
3. mkdir /mnt/nullb/nullb0
4. echo 1 > /mnt/nullb/nullb0/power
5. echo 4 > /mnt/nullb/nullb0/submit_queues
6. rmdir /mnt/nullb/nullb0
In step 4, will alloc 9 tags (8 submit queues and 1 poll queue), then
in step 5, new_nr_hw_queues = 5 (4 submit queues and 1 poll queue).
At last in step 6, only these 5 tags are freed, the other 4 tags leaked. |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: TC, Fix internal port memory leak
The flow rule can be splited, and the extra post_act rules are added
to post_act table. It's possible to trigger memleak when the rule
forwards packets from internal port and over tunnel, in the case that,
for example, CT 'new' state offload is allowed. As int_port object is
assigned to the flow attribute of post_act rule, and its refcnt is
incremented by mlx5e_tc_int_port_get(), but mlx5e_tc_int_port_put() is
not called, the refcnt is never decremented, then int_port is never
freed.
The kmemleak reports the following error:
unreferenced object 0xffff888128204b80 (size 64):
comm "handler20", pid 50121, jiffies 4296973009 (age 642.932s)
hex dump (first 32 bytes):
01 00 00 00 19 00 00 00 03 f0 00 00 04 00 00 00 ................
98 77 67 41 81 88 ff ff 98 77 67 41 81 88 ff ff .wgA.....wgA....
backtrace:
[<00000000e992680d>] kmalloc_trace+0x27/0x120
[<000000009e945a98>] mlx5e_tc_int_port_get+0x3f3/0xe20 [mlx5_core]
[<0000000035a537f0>] mlx5e_tc_add_fdb_flow+0x473/0xcf0 [mlx5_core]
[<0000000070c2cec6>] __mlx5e_add_fdb_flow+0x7cf/0xe90 [mlx5_core]
[<000000005cc84048>] mlx5e_configure_flower+0xd40/0x4c40 [mlx5_core]
[<000000004f8a2031>] mlx5e_rep_indr_offload.isra.0+0x10e/0x1c0 [mlx5_core]
[<000000007df797dc>] mlx5e_rep_indr_setup_tc_cb+0x90/0x130 [mlx5_core]
[<0000000016c15cc3>] tc_setup_cb_add+0x1cf/0x410
[<00000000a63305b4>] fl_hw_replace_filter+0x38f/0x670 [cls_flower]
[<000000008bc9e77c>] fl_change+0x1fd5/0x4430 [cls_flower]
[<00000000e7f766e4>] tc_new_tfilter+0x867/0x2010
[<00000000e101c0ef>] rtnetlink_rcv_msg+0x6fc/0x9f0
[<00000000e1111d44>] netlink_rcv_skb+0x12c/0x360
[<0000000082dd6c8b>] netlink_unicast+0x438/0x710
[<00000000fc568f70>] netlink_sendmsg+0x794/0xc50
[<0000000016e92590>] sock_sendmsg+0xc5/0x190
So fix this by moving int_port cleanup code to the flow attribute
free helper, which is used by all the attribute free cases. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: bpf_sk_storage: Fix invalid wait context lockdep report
'./test_progs -t test_local_storage' reported a splat:
[ 27.137569] =============================
[ 27.138122] [ BUG: Invalid wait context ]
[ 27.138650] 6.5.0-03980-gd11ae1b16b0a #247 Tainted: G O
[ 27.139542] -----------------------------
[ 27.140106] test_progs/1729 is trying to lock:
[ 27.140713] ffff8883ef047b88 (stock_lock){-.-.}-{3:3}, at: local_lock_acquire+0x9/0x130
[ 27.141834] other info that might help us debug this:
[ 27.142437] context-{5:5}
[ 27.142856] 2 locks held by test_progs/1729:
[ 27.143352] #0: ffffffff84bcd9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x40
[ 27.144492] #1: ffff888107deb2c0 (&storage->lock){..-.}-{2:2}, at: bpf_local_storage_update+0x39e/0x8e0
[ 27.145855] stack backtrace:
[ 27.146274] CPU: 0 PID: 1729 Comm: test_progs Tainted: G O 6.5.0-03980-gd11ae1b16b0a #247
[ 27.147550] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[ 27.149127] Call Trace:
[ 27.149490] <TASK>
[ 27.149867] dump_stack_lvl+0x130/0x1d0
[ 27.152609] dump_stack+0x14/0x20
[ 27.153131] __lock_acquire+0x1657/0x2220
[ 27.153677] lock_acquire+0x1b8/0x510
[ 27.157908] local_lock_acquire+0x29/0x130
[ 27.159048] obj_cgroup_charge+0xf4/0x3c0
[ 27.160794] slab_pre_alloc_hook+0x28e/0x2b0
[ 27.161931] __kmem_cache_alloc_node+0x51/0x210
[ 27.163557] __kmalloc+0xaa/0x210
[ 27.164593] bpf_map_kzalloc+0xbc/0x170
[ 27.165147] bpf_selem_alloc+0x130/0x510
[ 27.166295] bpf_local_storage_update+0x5aa/0x8e0
[ 27.167042] bpf_fd_sk_storage_update_elem+0xdb/0x1a0
[ 27.169199] bpf_map_update_value+0x415/0x4f0
[ 27.169871] map_update_elem+0x413/0x550
[ 27.170330] __sys_bpf+0x5e9/0x640
[ 27.174065] __x64_sys_bpf+0x80/0x90
[ 27.174568] do_syscall_64+0x48/0xa0
[ 27.175201] entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[ 27.175932] RIP: 0033:0x7effb40e41ad
[ 27.176357] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d8
[ 27.179028] RSP: 002b:00007ffe64c21fc8 EFLAGS: 00000202 ORIG_RAX: 0000000000000141
[ 27.180088] RAX: ffffffffffffffda RBX: 00007ffe64c22768 RCX: 00007effb40e41ad
[ 27.181082] RDX: 0000000000000020 RSI: 00007ffe64c22008 RDI: 0000000000000002
[ 27.182030] RBP: 00007ffe64c21ff0 R08: 0000000000000000 R09: 00007ffe64c22788
[ 27.183038] R10: 0000000000000064 R11: 0000000000000202 R12: 0000000000000000
[ 27.184006] R13: 00007ffe64c22788 R14: 00007effb42a1000 R15: 0000000000000000
[ 27.184958] </TASK>
It complains about acquiring a local_lock while holding a raw_spin_lock.
It means it should not allocate memory while holding a raw_spin_lock
since it is not safe for RT.
raw_spin_lock is needed because bpf_local_storage supports tracing
context. In particular for task local storage, it is easy to
get a "current" task PTR_TO_BTF_ID in tracing bpf prog.
However, task (and cgroup) local storage has already been moved to
bpf mem allocator which can be used after raw_spin_lock.
The splat is for the sk storage. For sk (and inode) storage,
it has not been moved to bpf mem allocator. Using raw_spin_lock or not,
kzalloc(GFP_ATOMIC) could theoretically be unsafe in tracing context.
However, the local storage helper requires a verifier accepted
sk pointer (PTR_TO_BTF_ID), it is hypothetical if that (mean running
a bpf prog in a kzalloc unsafe context and also able to hold a verifier
accepted sk pointer) could happen.
This patch avoids kzalloc after raw_spin_lock to silent the splat.
There is an existing kzalloc before the raw_spin_lock. At that point,
a kzalloc is very likely required because a lookup has just been done
before. Thus, this patch always does the kzalloc before acq
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
drm/msm/dp: Drop aux devices together with DP controller
Using devres to depopulate the aux bus made sure that upon a probe
deferral the EDP panel device would be destroyed and recreated upon next
attempt.
But the struct device which the devres is tied to is the DPUs
(drm_dev->dev), which may be happen after the DP controller is torn
down.
Indications of this can be seen in the commonly seen EDID-hexdump full
of zeros in the log, or the occasional/rare KASAN fault where the
panel's attempt to read the EDID information causes a use after free on
DP resources.
It's tempting to move the devres to the DP controller's struct device,
but the resources used by the device(s) on the aux bus are explicitly
torn down in the error path. The KASAN-reported use-after-free also
remains, as the DP aux "module" explicitly frees its devres-allocated
memory in this code path.
As such, explicitly depopulate the aux bus in the error path, and in the
component unbind path, to avoid these issues.
Patchwork: https://patchwork.freedesktop.org/patch/542163/ |
