| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix NULL pointer dereference in VRAM logic for APU devices
Previously, APU platforms (and other scenarios with uninitialized VRAM managers)
triggered a NULL pointer dereference in `ttm_resource_manager_usage()`. The root
cause is not that the `struct ttm_resource_manager *man` pointer itself is NULL,
but that `man->bdev` (the backing device pointer within the manager) remains
uninitialized (NULL) on APUs—since APUs lack dedicated VRAM and do not fully
set up VRAM manager structures. When `ttm_resource_manager_usage()` attempts to
acquire `man->bdev->lru_lock`, it dereferences the NULL `man->bdev`, leading to
a kernel OOPS.
1. **amdgpu_cs.c**: Extend the existing bandwidth control check in
`amdgpu_cs_get_threshold_for_moves()` to include a check for
`ttm_resource_manager_used()`. If the manager is not used (uninitialized
`bdev`), return 0 for migration thresholds immediately—skipping VRAM-specific
logic that would trigger the NULL dereference.
2. **amdgpu_kms.c**: Update the `AMDGPU_INFO_VRAM_USAGE` ioctl and memory info
reporting to use a conditional: if the manager is used, return the real VRAM
usage; otherwise, return 0. This avoids accessing `man->bdev` when it is
NULL.
3. **amdgpu_virt.c**: Modify the vf2pf (virtual function to physical function)
data write path. Use `ttm_resource_manager_used()` to check validity: if the
manager is usable, calculate `fb_usage` from VRAM usage; otherwise, set
`fb_usage` to 0 (APUs have no discrete framebuffer to report).
This approach is more robust than APU-specific checks because it:
- Works for all scenarios where the VRAM manager is uninitialized (not just APUs),
- Aligns with TTM's design by using its native helper function,
- Preserves correct behavior for discrete GPUs (which have fully initialized
`man->bdev` and pass the `ttm_resource_manager_used()` check).
v4: use ttm_resource_manager_used(&adev->mman.vram_mgr.manager) instead of checking the adev->gmc.is_app_apu flag (Christian) |
| In the Linux kernel, the following vulnerability has been resolved:
smb/server: fix possible refcount leak in smb2_sess_setup()
Reference count of ksmbd_session will leak when session need reconnect.
Fix this by adding the missing ksmbd_user_session_put(). |
| In the Linux kernel, the following vulnerability has been resolved:
fanotify: Validate the return value of mnt_ns_from_dentry() before dereferencing
The function do_fanotify_mark() does not validate if
mnt_ns_from_dentry() returns NULL before dereferencing mntns->user_ns.
This causes a NULL pointer dereference in do_fanotify_mark() if the
path is not a mount namespace object.
Fix this by checking mnt_ns_from_dentry()'s return value before
dereferencing it.
Before the patch
$ gcc fanotify_nullptr.c -o fanotify_nullptr
$ mkdir A
$ ./fanotify_nullptr
Fanotify fd: 3
fanotify_mark: Operation not permitted
$ unshare -Urm
Fanotify fd: 3
Killed
int main(void){
int ffd;
ffd = fanotify_init(FAN_CLASS_NOTIF | FAN_REPORT_MNT, 0);
if(ffd < 0){
perror("fanotify_init");
exit(EXIT_FAILURE);
}
printf("Fanotify fd: %d\n",ffd);
if(fanotify_mark(ffd, FAN_MARK_ADD | FAN_MARK_MNTNS,
FAN_MNT_ATTACH, AT_FDCWD, "A") < 0){
perror("fanotify_mark");
exit(EXIT_FAILURE);
}
return 0;
}
After the patch
$ gcc fanotify_nullptr.c -o fanotify_nullptr
$ mkdir A
$ ./fanotify_nullptr
Fanotify fd: 3
fanotify_mark: Operation not permitted
$ unshare -Urm
Fanotify fd: 3
fanotify_mark: Invalid argument
[ 25.694973] BUG: kernel NULL pointer dereference, address: 0000000000000038
[ 25.695006] #PF: supervisor read access in kernel mode
[ 25.695012] #PF: error_code(0x0000) - not-present page
[ 25.695017] PGD 109a30067 P4D 109a30067 PUD 142b46067 PMD 0
[ 25.695025] Oops: Oops: 0000 [#1] SMP NOPTI
[ 25.695032] CPU: 4 UID: 1000 PID: 1478 Comm: fanotify_nullpt Not
tainted 6.17.0-rc4 #1 PREEMPT(lazy)
[ 25.695040] Hardware name: VMware, Inc. VMware Virtual
Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
[ 25.695049] RIP: 0010:do_fanotify_mark+0x817/0x950
[ 25.695066] Code: 04 00 00 e9 45 fd ff ff 48 8b 7c 24 48 4c 89 54
24 18 4c 89 5c 24 10 4c 89 0c 24 e8 b3 11 fc ff 4c 8b 54 24 18 4c 8b
5c 24 10 <48> 8b 78 38 4c 8b 0c 24 49 89 c4 e9 13 fd ff ff 8b 4c 24 28
85 c9
[ 25.695081] RSP: 0018:ffffd31c469e3c08 EFLAGS: 00010203
[ 25.695104] RAX: 0000000000000000 RBX: 0000000001000000 RCX: ffff8eb48aebd220
[ 25.695110] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8eb4835e8180
[ 25.695115] RBP: 0000000000000111 R08: 0000000000000000 R09: 0000000000000000
[ 25.695142] R10: ffff8eb48a7d56c0 R11: ffff8eb482bede00 R12: 00000000004012a7
[ 25.695148] R13: 0000000000000110 R14: 0000000000000001 R15: ffff8eb48a7d56c0
[ 25.695154] FS: 00007f8733bda740(0000) GS:ffff8eb61ce5f000(0000)
knlGS:0000000000000000
[ 25.695162] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 25.695170] CR2: 0000000000000038 CR3: 0000000136994006 CR4: 00000000003706f0
[ 25.695201] Call Trace:
[ 25.695209] <TASK>
[ 25.695215] __x64_sys_fanotify_mark+0x1f/0x30
[ 25.695222] do_syscall_64+0x82/0x2c0
... |
| The VAPIX Edge storage API that allowed a privilege escalation, enabling a VAPIX administrator-privileged user to gain Linux Root privileges. This flaw can only be exploited after authenticating with an administrator-privileged service account. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/secretmem: fix use-after-free race in fault handler
When a page fault occurs in a secret memory file created with
`memfd_secret(2)`, the kernel will allocate a new folio for it, mark the
underlying page as not-present in the direct map, and add it to the file
mapping.
If two tasks cause a fault in the same page concurrently, both could end
up allocating a folio and removing the page from the direct map, but only
one would succeed in adding the folio to the file mapping. The task that
failed undoes the effects of its attempt by (a) freeing the folio again
and (b) putting the page back into the direct map. However, by doing
these two operations in this order, the page becomes available to the
allocator again before it is placed back in the direct mapping.
If another task attempts to allocate the page between (a) and (b), and the
kernel tries to access it via the direct map, it would result in a
supervisor not-present page fault.
Fix the ordering to restore the direct map before the folio is freed. |
| In the Linux kernel, the following vulnerability has been resolved:
cifs: client: fix memory leak in smb3_fs_context_parse_param
The user calls fsconfig twice, but when the program exits, free() only
frees ctx->source for the second fsconfig, not the first.
Regarding fc->source, there is no code in the fs context related to its
memory reclamation.
To fix this memory leak, release the source memory corresponding to ctx
or fc before each parsing.
syzbot reported:
BUG: memory leak
unreferenced object 0xffff888128afa360 (size 96):
backtrace (crc 79c9c7ba):
kstrdup+0x3c/0x80 mm/util.c:84
smb3_fs_context_parse_param+0x229b/0x36c0 fs/smb/client/fs_context.c:1444
BUG: memory leak
unreferenced object 0xffff888112c7d900 (size 96):
backtrace (crc 79c9c7ba):
smb3_fs_context_fullpath+0x70/0x1b0 fs/smb/client/fs_context.c:629
smb3_fs_context_parse_param+0x2266/0x36c0 fs/smb/client/fs_context.c:1438 |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: also call xfrm_state_delete_tunnel at destroy time for states that were never added
In commit b441cf3f8c4b ("xfrm: delete x->tunnel as we delete x"), I
missed the case where state creation fails between full
initialization (->init_state has been called) and being inserted on
the lists.
In this situation, ->init_state has been called, so for IPcomp
tunnels, the fallback tunnel has been created and added onto the
lists, but the user state never gets added, because we fail before
that. The user state doesn't go through __xfrm_state_delete, so we
don't call xfrm_state_delete_tunnel for those states, and we end up
leaking the FB tunnel.
There are several codepaths affected by this: the add/update paths, in
both net/key and xfrm, and the migrate code (xfrm_migrate,
xfrm_state_migrate). A "proper" rollback of the init_state work would
probably be doable in the add/update code, but for migrate it gets
more complicated as multiple states may be involved.
At some point, the new (not-inserted) state will be destroyed, so call
xfrm_state_delete_tunnel during xfrm_state_gc_destroy. Most states
will have their fallback tunnel cleaned up during __xfrm_state_delete,
which solves the issue that b441cf3f8c4b (and other patches before it)
aimed at. All states (including FB tunnels) will be removed from the
lists once xfrm_state_fini has called flush_work(&xfrm_state_gc_work). |
| In the Linux kernel, the following vulnerability has been resolved:
iio: imu: st_lsm6dsx: fix iio_chan_spec for sensors without event detection
The st_lsm6dsx_acc_channels array of struct iio_chan_spec has a non-NULL
event_spec field, indicating support for IIO events. However, event
detection is not supported for all sensors, and if userspace tries to
configure accelerometer wakeup events on a sensor device that does not
support them (e.g. LSM6DS0), st_lsm6dsx_write_event() dereferences a NULL
pointer when trying to write to the wakeup register.
Define an additional struct iio_chan_spec array whose members have a NULL
event_spec field, and use this array instead of st_lsm6dsx_acc_channels for
sensors without event detection capability. |
| In the Linux kernel, the following vulnerability has been resolved:
vfat: fix missing sb_min_blocksize() return value checks
When emulating an nvme device on qemu with both logical_block_size and
physical_block_size set to 8 KiB, but without format, a kernel panic
was triggered during the early boot stage while attempting to mount a
vfat filesystem.
[95553.682035] EXT4-fs (nvme0n1): unable to set blocksize
[95553.684326] EXT4-fs (nvme0n1): unable to set blocksize
[95553.686501] EXT4-fs (nvme0n1): unable to set blocksize
[95553.696448] ISOFS: unsupported/invalid hardware sector size 8192
[95553.697117] ------------[ cut here ]------------
[95553.697567] kernel BUG at fs/buffer.c:1582!
[95553.697984] Oops: invalid opcode: 0000 [#1] SMP NOPTI
[95553.698602] CPU: 0 UID: 0 PID: 7212 Comm: mount Kdump: loaded Not tainted 6.18.0-rc2+ #38 PREEMPT(voluntary)
[95553.699511] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[95553.700534] RIP: 0010:folio_alloc_buffers+0x1bb/0x1c0
[95553.701018] Code: 48 8b 15 e8 93 18 02 65 48 89 35 e0 93 18 02 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff c3 cc cc cc cc <0f> 0b 90 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f
[95553.702648] RSP: 0018:ffffd1b0c676f990 EFLAGS: 00010246
[95553.703132] RAX: ffff8cfc4176d820 RBX: 0000000000508c48 RCX: 0000000000000001
[95553.703805] RDX: 0000000000002000 RSI: 0000000000000000 RDI: 0000000000000000
[95553.704481] RBP: ffffd1b0c676f9c8 R08: 0000000000000000 R09: 0000000000000000
[95553.705148] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
[95553.705816] R13: 0000000000002000 R14: fffff8bc8257e800 R15: 0000000000000000
[95553.706483] FS: 000072ee77315840(0000) GS:ffff8cfdd2c8d000(0000) knlGS:0000000000000000
[95553.707248] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[95553.707782] CR2: 00007d8f2a9e5a20 CR3: 0000000039d0c006 CR4: 0000000000772ef0
[95553.708439] PKRU: 55555554
[95553.708734] Call Trace:
[95553.709015] <TASK>
[95553.709266] __getblk_slow+0xd2/0x230
[95553.709641] ? find_get_block_common+0x8b/0x530
[95553.710084] bdev_getblk+0x77/0xa0
[95553.710449] __bread_gfp+0x22/0x140
[95553.710810] fat_fill_super+0x23a/0xfc0
[95553.711216] ? __pfx_setup+0x10/0x10
[95553.711580] ? __pfx_vfat_fill_super+0x10/0x10
[95553.712014] vfat_fill_super+0x15/0x30
[95553.712401] get_tree_bdev_flags+0x141/0x1e0
[95553.712817] get_tree_bdev+0x10/0x20
[95553.713177] vfat_get_tree+0x15/0x20
[95553.713550] vfs_get_tree+0x2a/0x100
[95553.713910] vfs_cmd_create+0x62/0xf0
[95553.714273] __do_sys_fsconfig+0x4e7/0x660
[95553.714669] __x64_sys_fsconfig+0x20/0x40
[95553.715062] x64_sys_call+0x21ee/0x26a0
[95553.715453] do_syscall_64+0x80/0x670
[95553.715816] ? __fs_parse+0x65/0x1e0
[95553.716172] ? fat_parse_param+0x103/0x4b0
[95553.716587] ? vfs_parse_fs_param_source+0x21/0xa0
[95553.717034] ? __do_sys_fsconfig+0x3d9/0x660
[95553.717548] ? __x64_sys_fsconfig+0x20/0x40
[95553.717957] ? x64_sys_call+0x21ee/0x26a0
[95553.718360] ? do_syscall_64+0xb8/0x670
[95553.718734] ? __x64_sys_fsconfig+0x20/0x40
[95553.719141] ? x64_sys_call+0x21ee/0x26a0
[95553.719545] ? do_syscall_64+0xb8/0x670
[95553.719922] ? x64_sys_call+0x1405/0x26a0
[95553.720317] ? do_syscall_64+0xb8/0x670
[95553.720702] ? __x64_sys_close+0x3e/0x90
[95553.721080] ? x64_sys_call+0x1b5e/0x26a0
[95553.721478] ? do_syscall_64+0xb8/0x670
[95553.721841] ? irqentry_exit+0x43/0x50
[95553.722211] ? exc_page_fault+0x90/0x1b0
[95553.722681] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[95553.723166] RIP: 0033:0x72ee774f3afe
[95553.723562] Code: 73 01 c3 48 8b 0d 0a 33 0f 00 f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 49 89 ca b8 af 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d da 32 0f 00 f7 d8 64 89 01 48
[95553.725188] RSP: 002b:00007ffe97148978 EFLAGS: 00000246 ORIG_RAX: 00000000000001af
[95553.725892] RAX: ffffffffffffffda RBX:
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
remoteproc: pru: Fix potential NULL pointer dereference in pru_rproc_set_ctable()
pru_rproc_set_ctable() accessed rproc->priv before the IS_ERR_OR_NULL
check, which could lead to a null pointer dereference. Move the pru
assignment, ensuring we never dereference a NULL rproc pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
vhost: vringh: Fix copy_to_iter return value check
The return value of copy_to_iter can't be negative, check whether the
copied length is equal to the requested length instead of checking for
negative values. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7996: Check phy before init msta_link in mt7996_mac_sta_add_links()
In order to avoid a possible NULL pointer dereference in
mt7996_mac_sta_init_link routine, move the phy pointer check before
running mt7996_mac_sta_init_link() in mt7996_mac_sta_add_links routine. |
| NULL Pointer Dereference vulnerability in Avast Antivirus on MacOS, Avast Anitvirus on Linux when scanning a malformed Windows PE file causes the antivirus process to crash.This issue affects Antivirus: 16.0.0; Anitvirus: 3.0.3. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_rndis: Refactor bind path to use __free()
After an bind/unbind cycle, the rndis->notify_req is left stale. If a
subsequent bind fails, the unified error label attempts to free this
stale request, leading to a NULL pointer dereference when accessing
ep->ops->free_request.
Refactor the error handling in the bind path to use the __free()
automatic cleanup mechanism. |
| In the Linux kernel, the following vulnerability has been resolved:
md: avoid repeated calls to del_gendisk
There is a uaf problem which is found by case 23rdev-lifetime:
Oops: general protection fault, probably for non-canonical address 0xdead000000000122
RIP: 0010:bdi_unregister+0x4b/0x170
Call Trace:
<TASK>
__del_gendisk+0x356/0x3e0
mddev_unlock+0x351/0x360
rdev_attr_store+0x217/0x280
kernfs_fop_write_iter+0x14a/0x210
vfs_write+0x29e/0x550
ksys_write+0x74/0xf0
do_syscall_64+0xbb/0x380
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff5250a177e
The sequence is:
1. rdev remove path gets reconfig_mutex
2. rdev remove path release reconfig_mutex in mddev_unlock
3. md stop calls do_md_stop and sets MD_DELETED
4. rdev remove path calls del_gendisk because MD_DELETED is set
5. md stop path release reconfig_mutex and calls del_gendisk again
So there is a race condition we should resolve. This patch adds a
flag MD_DO_DELETE to avoid the race condition. |
| In the Linux kernel, the following vulnerability has been resolved:
exfat: fix divide-by-zero in exfat_allocate_bitmap
The variable max_ra_count can be 0 in exfat_allocate_bitmap(),
which causes a divide-by-zero error in the subsequent modulo operation
(i % max_ra_count), leading to a system crash.
When max_ra_count is 0, it means that readahead is not used. This patch
load the bitmap without readahead. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: mpt3sas: Fix crash in transport port remove by using ioc_info()
During mpt3sas_transport_port_remove(), messages were logged with
dev_printk() against &mpt3sas_port->port->dev. At this point the SAS
transport device may already be partially unregistered or freed, leading
to a crash when accessing its struct device.
Using ioc_info(), which logs via the PCI device (ioc->pdev->dev),
guaranteed to remain valid until driver removal.
[83428.295776] Oops: general protection fault, probably for non-canonical address 0x6f702f323a33312d: 0000 [#1] SMP NOPTI
[83428.295785] CPU: 145 UID: 0 PID: 113296 Comm: rmmod Kdump: loaded Tainted: G OE 6.16.0-rc1+ #1 PREEMPT(voluntary)
[83428.295792] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
[83428.295795] Hardware name: Dell Inc. Precision 7875 Tower/, BIOS 89.1.67 02/23/2024
[83428.295799] RIP: 0010:__dev_printk+0x1f/0x70
[83428.295805] Code: 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 49 89 d1 48 85 f6 74 52 4c 8b 46 50 4d 85 c0 74 1f 48 8b 46 68 48 85 c0 74 22 <48> 8b 08 0f b6 7f 01 48 c7 c2 db e8 42 ad 83 ef 30 e9 7b f8 ff ff
[83428.295813] RSP: 0018:ff85aeafc3137bb0 EFLAGS: 00010206
[83428.295817] RAX: 6f702f323a33312d RBX: ff4290ee81292860 RCX: 5000cca25103be32
[83428.295820] RDX: ff85aeafc3137bb8 RSI: ff4290eeb1966c00 RDI: ffffffffc1560845
[83428.295823] RBP: ff85aeafc3137c18 R08: 74726f702f303a33 R09: ff85aeafc3137bb8
[83428.295826] R10: ff85aeafc3137b18 R11: ff4290f5bd60fe68 R12: ff4290ee81290000
[83428.295830] R13: ff4290ee6e345de0 R14: ff4290ee81290000 R15: ff4290ee6e345e30
[83428.295833] FS: 00007fd9472a6740(0000) GS:ff4290f5ce96b000(0000) knlGS:0000000000000000
[83428.295837] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[83428.295840] CR2: 00007f242b4db238 CR3: 00000002372b8006 CR4: 0000000000771ef0
[83428.295844] PKRU: 55555554
[83428.295846] Call Trace:
[83428.295848] <TASK>
[83428.295850] _dev_printk+0x5c/0x80
[83428.295857] ? srso_alias_return_thunk+0x5/0xfbef5
[83428.295863] mpt3sas_transport_port_remove+0x1c7/0x420 [mpt3sas]
[83428.295882] _scsih_remove_device+0x21b/0x280 [mpt3sas]
[83428.295894] ? _scsih_expander_node_remove+0x108/0x140 [mpt3sas]
[83428.295906] ? srso_alias_return_thunk+0x5/0xfbef5
[83428.295910] mpt3sas_device_remove_by_sas_address.part.0+0x8f/0x110 [mpt3sas]
[83428.295921] _scsih_expander_node_remove+0x129/0x140 [mpt3sas]
[83428.295933] _scsih_expander_node_remove+0x6a/0x140 [mpt3sas]
[83428.295944] scsih_remove+0x3f0/0x4a0 [mpt3sas]
[83428.295957] pci_device_remove+0x3b/0xb0
[83428.295962] device_release_driver_internal+0x193/0x200
[83428.295968] driver_detach+0x44/0x90
[83428.295971] bus_remove_driver+0x69/0xf0
[83428.295975] pci_unregister_driver+0x2a/0xb0
[83428.295979] _mpt3sas_exit+0x1f/0x300 [mpt3sas]
[83428.295991] __do_sys_delete_module.constprop.0+0x174/0x310
[83428.295997] ? srso_alias_return_thunk+0x5/0xfbef5
[83428.296000] ? __x64_sys_getdents64+0x9a/0x110
[83428.296005] ? srso_alias_return_thunk+0x5/0xfbef5
[83428.296009] ? syscall_trace_enter+0xf6/0x1b0
[83428.296014] do_syscall_64+0x7b/0x2c0
[83428.296019] ? srso_alias_return_thunk+0x5/0xfbef5
[83428.296023] entry_SYSCALL_64_after_hwframe+0x76/0x7e |
| 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:
platform/x86/amd/pmc: Add support for Van Gogh SoC
The ROG Xbox Ally (non-X) SoC features a similar architecture to the
Steam Deck. While the Steam Deck supports S3 (s2idle causes a crash),
this support was dropped by the Xbox Ally which only S0ix suspend.
Since the handler is missing here, this causes the device to not suspend
and the AMD GPU driver to crash while trying to resume afterwards due to
a power hang. |
| In the Linux kernel, the following vulnerability has been resolved:
comedi: c6xdigio: Fix invalid PNP driver unregistration
The Comedi low-level driver "c6xdigio" seems to be for a parallel port
connected device. When the Comedi core calls the driver's Comedi
"attach" handler `c6xdigio_attach()` to configure a Comedi to use this
driver, it tries to enable the parallel port PNP resources by
registering a PNP driver with `pnp_register_driver()`, but ignores the
return value. (The `struct pnp_driver` it uses has only the `name` and
`id_table` members filled in.) The driver's Comedi "detach" handler
`c6xdigio_detach()` unconditionally unregisters the PNP driver with
`pnp_unregister_driver()`.
It is possible for `c6xdigio_attach()` to return an error before it
calls `pnp_register_driver()` and it is possible for the call to
`pnp_register_driver()` to return an error (that is ignored). In both
cases, the driver should not be calling `pnp_unregister_driver()` as it
does in `c6xdigio_detach()`. (Note that `c6xdigio_detach()` will be
called by the Comedi core if `c6xdigio_attach()` returns an error, or if
the Comedi core decides to detach the Comedi device from the driver for
some other reason.)
The unconditional call to `pnp_unregister_driver()` without a previous
successful call to `pnp_register_driver()` will cause
`driver_unregister()` to issue a warning "Unexpected driver
unregister!". This was detected by Syzbot [1].
Also, the PNP driver registration and unregistration should be done at
module init and exit time, respectively, not when attaching or detaching
Comedi devices to the driver. (There might be more than one Comedi
device being attached to the driver, although that is unlikely.)
Change the driver to do the PNP driver registration at module init time,
and the unregistration at module exit time. Since `c6xdigio_detach()`
now only calls `comedi_legacy_detach()`, remove the function and change
the Comedi driver "detach" handler to `comedi_legacy_detach`.
-------------------------------------------
[1] Syzbot sample crash report:
Unexpected driver unregister!
WARNING: CPU: 0 PID: 5970 at drivers/base/driver.c:273 driver_unregister drivers/base/driver.c:273 [inline]
WARNING: CPU: 0 PID: 5970 at drivers/base/driver.c:273 driver_unregister+0x90/0xb0 drivers/base/driver.c:270
Modules linked in:
CPU: 0 UID: 0 PID: 5970 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:driver_unregister drivers/base/driver.c:273 [inline]
RIP: 0010:driver_unregister+0x90/0xb0 drivers/base/driver.c:270
Code: 48 89 ef e8 c2 e6 82 fc 48 89 df e8 3a 93 ff ff 5b 5d e9 c3 6d d9 fb e8 be 6d d9 fb 90 48 c7 c7 e0 f8 1f 8c e8 51 a2 97 fb 90 <0f> 0b 90 90 5b 5d e9 a5 6d d9 fb e8 e0 f4 41 fc eb 94 e8 d9 f4 41
RSP: 0018:ffffc9000373f9a0 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffffff8ff24720 RCX: ffffffff817b6ee8
RDX: ffff88807c932480 RSI: ffffffff817b6ef5 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff8ff24660
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88814cca0000
FS: 000055556dab1500(0000) GS:ffff8881249d9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f77f285cd0 CR3: 000000007d871000 CR4: 00000000003526f0
Call Trace:
<TASK>
comedi_device_detach_locked+0x12f/0xa50 drivers/comedi/drivers.c:207
comedi_device_detach+0x67/0xb0 drivers/comedi/drivers.c:215
comedi_device_attach+0x43d/0x900 drivers/comedi/drivers.c:1011
do_devconfig_ioctl+0x1b1/0x710 drivers/comedi/comedi_fops.c:872
comedi_unlocked_ioctl+0x165d/0x2f00 drivers/comedi/comedi_fops.c:2178
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_sys
---truncated--- |
