| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
can: etas_es58x: fix potential NULL pointer dereference on udev->serial
The driver assumed that es58x_dev->udev->serial could never be NULL.
While this is true on commercially available devices, an attacker
could spoof the device identity providing a NULL USB serial number.
That would trigger a NULL pointer dereference.
Add a check on es58x_dev->udev->serial before accessing it. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: mpi3mr: Fix possible crash when setting up bsg fails
If bsg_setup_queue() fails, the bsg_queue is assigned a non-NULL value.
Consequently, in mpi3mr_bsg_exit(), the condition "if(!mrioc->bsg_queue)"
will not be satisfied, preventing execution from entering
bsg_remove_queue(), which could lead to the following crash:
BUG: kernel NULL pointer dereference, address: 000000000000041c
Call Trace:
<TASK>
mpi3mr_bsg_exit+0x1f/0x50 [mpi3mr]
mpi3mr_remove+0x6f/0x340 [mpi3mr]
pci_device_remove+0x3f/0xb0
device_release_driver_internal+0x19d/0x220
unbind_store+0xa4/0xb0
kernfs_fop_write_iter+0x11f/0x200
vfs_write+0x1fc/0x3e0
ksys_write+0x67/0xe0
do_syscall_64+0x38/0x80
entry_SYSCALL_64_after_hwframe+0x78/0xe2 |
| In the Linux kernel, the following vulnerability has been resolved:
OPP: fix dev_pm_opp_find_bw_*() when bandwidth table not initialized
If a driver calls dev_pm_opp_find_bw_ceil/floor() the retrieve bandwidth
from the OPP table but the bandwidth table was not created because the
interconnect properties were missing in the OPP consumer node, the
kernel will crash with:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004
...
pc : _read_bw+0x8/0x10
lr : _opp_table_find_key+0x9c/0x174
...
Call trace:
_read_bw+0x8/0x10 (P)
_opp_table_find_key+0x9c/0x174 (L)
_find_key+0x98/0x168
dev_pm_opp_find_bw_ceil+0x50/0x88
...
In order to fix the crash, create an assert function to check
if the bandwidth table was created before trying to get a
bandwidth with _read_bw(). |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btbcm: Fix NULL deref in btbcm_get_board_name()
devm_kstrdup() can return a NULL pointer on failure,but this
returned value in btbcm_get_board_name() is not checked.
Add NULL check in btbcm_get_board_name(), to handle kernel NULL
pointer dereference error. |
| In the Linux kernel, the following vulnerability has been resolved:
nfs: Fix oops in nfs_netfs_init_request() when copying to cache
When netfslib wants to copy some data that has just been read on behalf of
nfs, it creates a new write request and calls nfs_netfs_init_request() to
initialise it, but with a NULL file pointer. This causes
nfs_file_open_context() to oops - however, we don't actually need the nfs
context as we're only going to write to the cache.
Fix this by just returning if we aren't given a file pointer and emit a
warning if the request was for something other than copy-to-cache.
Further, fix nfs_netfs_free_request() so that it doesn't try to free the
context if the pointer is NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: typec: tcpci: fix NULL pointer issue on shared irq case
The tcpci_irq() may meet below NULL pointer dereference issue:
[ 2.641851] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
[ 2.641951] status 0x1, 0x37f
[ 2.650659] Mem abort info:
[ 2.656490] ESR = 0x0000000096000004
[ 2.660230] EC = 0x25: DABT (current EL), IL = 32 bits
[ 2.665532] SET = 0, FnV = 0
[ 2.668579] EA = 0, S1PTW = 0
[ 2.671715] FSC = 0x04: level 0 translation fault
[ 2.676584] Data abort info:
[ 2.679459] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[ 2.684936] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[ 2.689980] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[ 2.695284] [0000000000000010] user address but active_mm is swapper
[ 2.701632] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[ 2.707883] Modules linked in:
[ 2.710936] CPU: 1 UID: 0 PID: 87 Comm: irq/111-2-0051 Not tainted 6.12.0-rc6-06316-g7f63786ad3d1-dirty #4
[ 2.720570] Hardware name: NXP i.MX93 11X11 EVK board (DT)
[ 2.726040] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 2.732989] pc : tcpci_irq+0x38/0x318
[ 2.736647] lr : _tcpci_irq+0x14/0x20
[ 2.740295] sp : ffff80008324bd30
[ 2.743597] x29: ffff80008324bd70 x28: ffff800080107894 x27: ffff800082198f70
[ 2.750721] x26: ffff0000050e6680 x25: ffff000004d172ac x24: ffff0000050f0000
[ 2.757845] x23: ffff000004d17200 x22: 0000000000000001 x21: ffff0000050f0000
[ 2.764969] x20: ffff000004d17200 x19: 0000000000000000 x18: 0000000000000001
[ 2.772093] x17: 0000000000000000 x16: ffff80008183d8a0 x15: ffff00007fbab040
[ 2.779217] x14: ffff00007fb918c0 x13: 0000000000000000 x12: 000000000000017a
[ 2.786341] x11: 0000000000000001 x10: 0000000000000a90 x9 : ffff80008324bd00
[ 2.793465] x8 : ffff0000050f0af0 x7 : ffff00007fbaa840 x6 : 0000000000000031
[ 2.800589] x5 : 000000000000017a x4 : 0000000000000002 x3 : 0000000000000002
[ 2.807713] x2 : ffff80008324bd3a x1 : 0000000000000010 x0 : 0000000000000000
[ 2.814838] Call trace:
[ 2.817273] tcpci_irq+0x38/0x318
[ 2.820583] _tcpci_irq+0x14/0x20
[ 2.823885] irq_thread_fn+0x2c/0xa8
[ 2.827456] irq_thread+0x16c/0x2f4
[ 2.830940] kthread+0x110/0x114
[ 2.834164] ret_from_fork+0x10/0x20
[ 2.837738] Code: f9426420 f9001fe0 d2800000 52800201 (f9400a60)
This may happen on shared irq case. Such as two Type-C ports share one
irq. After the first port finished tcpci_register_port(), it may trigger
interrupt. However, if the interrupt comes by chance the 2nd port finishes
devm_request_threaded_irq(), the 2nd port interrupt handler will run at
first. Then the above issue happens due to tcpci is still a NULL pointer
in tcpci_irq() when dereference to regmap.
devm_request_threaded_irq()
<-- port1 irq comes
disable_irq(client->irq);
tcpci_register_port()
This will restore the logic to the state before commit (77e85107a771 "usb:
typec: tcpci: support edge irq").
However, moving tcpci_register_port() earlier creates a problem when use
edge irq because tcpci_init() will be called before
devm_request_threaded_irq(). The tcpci_init() writes the ALERT_MASK to
the hardware to tell it to start generating interrupts but we're not ready
to deal with them yet, then the ALERT events may be missed and ALERT line
will not recover to high level forever. To avoid the issue, this will also
set ALERT_MASK register after devm_request_threaded_irq() return. |
| In the Linux kernel, the following vulnerability has been resolved:
net: Drop the lock in skb_may_tx_timestamp()
skb_may_tx_timestamp() may acquire sock::sk_callback_lock. The lock must
not be taken in IRQ context, only softirq is okay. A few drivers receive
the timestamp via a dedicated interrupt and complete the TX timestamp
from that handler. This will lead to a deadlock if the lock is already
write-locked on the same CPU.
Taking the lock can be avoided. The socket (pointed by the skb) will
remain valid until the skb is released. The ->sk_socket and ->file
member will be set to NULL once the user closes the socket which may
happen before the timestamp arrives.
If we happen to observe the pointer while the socket is closing but
before the pointer is set to NULL then we may use it because both
pointer (and the file's cred member) are RCU freed.
Drop the lock. Use READ_ONCE() to obtain the individual pointer. Add a
matching WRITE_ONCE() where the pointer are cleared. |
| In the Linux kernel, the following vulnerability has been resolved:
phy: rockchip: samsung-hdptx: Set drvdata before enabling runtime PM
In some cases, rk_hdptx_phy_runtime_resume() may be invoked before
platform_set_drvdata() is executed in ->probe(), leading to a NULL
pointer dereference when using the return of dev_get_drvdata().
Ensure platform_set_drvdata() is called before devm_pm_runtime_enable(). |
| In the Linux kernel, the following vulnerability has been resolved:
PCI: endpoint: epf-mhi: Avoid NULL dereference if DT lacks 'mmio'
If platform_get_resource_byname() fails and returns NULL because DT lacks
an 'mmio' property for the MHI endpoint, dereferencing res->start will
cause a NULL pointer access. Add a check to prevent it.
[kwilczynski: error message update per the review feedback]
[bhelgaas: commit log] |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: fix NULL deref in cleanup_bearer()
syzbot found [1] that after blamed commit, ub->ubsock->sk
was NULL when attempting the atomic_dec() :
atomic_dec(&tipc_net(sock_net(ub->ubsock->sk))->wq_count);
Fix this by caching the tipc_net pointer.
[1]
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 0 UID: 0 PID: 5896 Comm: kworker/0:3 Not tainted 6.13.0-rc1-next-20241203-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events cleanup_bearer
RIP: 0010:read_pnet include/net/net_namespace.h:387 [inline]
RIP: 0010:sock_net include/net/sock.h:655 [inline]
RIP: 0010:cleanup_bearer+0x1f7/0x280 net/tipc/udp_media.c:820
Code: 18 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 3c f7 99 f6 48 8b 1b 48 83 c3 30 e8 f0 e4 60 00 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 1a f7 99 f6 49 83 c7 e8 48 8b 1b
RSP: 0018:ffffc9000410fb70 EFLAGS: 00010206
RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff88802fe45a00
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc9000410f900
RBP: ffff88807e1f0908 R08: ffffc9000410f907 R09: 1ffff92000821f20
R10: dffffc0000000000 R11: fffff52000821f21 R12: ffff888031d19980
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff88807e1f0918
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556ca050b000 CR3: 0000000031c0c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 |
| In the Linux kernel, the following vulnerability has been resolved:
gpiolib: Fix potential NULL pointer dereference in gpiod_get_label()
In `gpiod_get_label()`, it is possible that `srcu_dereference_check()` may
return a NULL pointer, leading to a scenario where `label->str` is accessed
without verifying if `label` itself is NULL.
This patch adds a proper NULL check for `label` before accessing
`label->str`. The check for `label->str != NULL` is removed because
`label->str` can never be NULL if `label` is not NULL.
This fixes the issue where the label name was being printed as `(efault)`
when dumping the sysfs GPIO file when `label == NULL`. |
| In the Linux kernel, the following vulnerability has been resolved:
tpm: Use auth only after NULL check in tpm_buf_check_hmac_response()
Dereference auth after NULL check in tpm_buf_check_hmac_response().
Otherwise, unless tpm2_sessions_init() was called, a call can cause NULL
dereference, when TCG_TPM2_HMAC is enabled.
[jarkko: adjusted the commit message.] |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring: fix error pbuf checking
Syz reports a problem, which boils down to NULL vs IS_ERR inconsistent
error handling in io_alloc_pbuf_ring().
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:__io_remove_buffers+0xac/0x700 io_uring/kbuf.c:341
Call Trace:
<TASK>
io_put_bl io_uring/kbuf.c:378 [inline]
io_destroy_buffers+0x14e/0x490 io_uring/kbuf.c:392
io_ring_ctx_free+0xa00/0x1070 io_uring/io_uring.c:2613
io_ring_exit_work+0x80f/0x8a0 io_uring/io_uring.c:2844
process_one_work kernel/workqueue.c:3231 [inline]
process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda: cs35l41: Possible null pointer dereference in cs35l41_hda_unbind()
The cs35l41_hda_unbind() function clears the hda_component entry
matching it's index and then dereferences the codec pointer held in the
first element of the hda_component array, this is an issue when the
device index was 0.
Instead use the codec pointer stashed in the cs35l41_hda structure as it
will still be valid. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/mediatek: Fix a null pointer crash in mtk_drm_crtc_finish_page_flip
It's possible that mtk_crtc->event is NULL in
mtk_drm_crtc_finish_page_flip().
pending_needs_vblank value is set by mtk_crtc->event, but in
mtk_drm_crtc_atomic_flush(), it's is not guarded by the same
lock in mtk_drm_finish_page_flip(), thus a race condition happens.
Consider the following case:
CPU1 CPU2
step 1:
mtk_drm_crtc_atomic_begin()
mtk_crtc->event is not null,
step 1:
mtk_drm_crtc_atomic_flush:
mtk_drm_crtc_update_config(
!!mtk_crtc->event)
step 2:
mtk_crtc_ddp_irq ->
mtk_drm_finish_page_flip:
lock
mtk_crtc->event set to null,
pending_needs_vblank set to false
unlock
pending_needs_vblank set to true,
step 2:
mtk_crtc_ddp_irq ->
mtk_drm_finish_page_flip called again,
pending_needs_vblank is still true
//null pointer
Instead of guarding the entire mtk_drm_crtc_atomic_flush(), it's more
efficient to just check if mtk_crtc->event is null before use. |
| In the Linux kernel, the following vulnerability has been resolved:
comedi: comedi_8255: Correct error in subdevice initialization
The refactoring done in commit 5c57b1ccecc7 ("comedi: comedi_8255: Rework
subdevice initialization functions") to the initialization of the io
field of struct subdev_8255_private broke all cards using the
drivers/comedi/drivers/comedi_8255.c module.
Prior to 5c57b1ccecc7, __subdev_8255_init() initialized the io field
in the newly allocated struct subdev_8255_private to the non-NULL
callback given to the function, otherwise it used a flag parameter to
select between subdev_8255_mmio and subdev_8255_io. The refactoring
removed that logic and the flag, as subdev_8255_mm_init() and
subdev_8255_io_init() now explicitly pass subdev_8255_mmio and
subdev_8255_io respectively to __subdev_8255_init(), only
__subdev_8255_init() never sets spriv->io to the supplied
callback. That spriv->io is NULL leads to a later BUG:
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: 0010 [#1] SMP PTI
CPU: 1 PID: 1210 Comm: systemd-udevd Not tainted 6.7.3-x86_64 #1
Hardware name: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffa3f1c02d7b78 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff91f847aefd00 RCX: 000000000000009b
RDX: 0000000000000003 RSI: 0000000000000001 RDI: ffff91f840f6fc00
RBP: ffff91f840f6fc00 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 000000000000005f R12: 0000000000000000
R13: 0000000000000000 R14: ffffffffc0102498 R15: ffff91f847ce6ba8
FS: 00007f72f4e8f500(0000) GS:ffff91f8d5c80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 000000010540e000 CR4: 00000000000406f0
Call Trace:
<TASK>
? __die_body+0x15/0x57
? page_fault_oops+0x2ef/0x33c
? insert_vmap_area.constprop.0+0xb6/0xd5
? alloc_vmap_area+0x529/0x5ee
? exc_page_fault+0x15a/0x489
? asm_exc_page_fault+0x22/0x30
__subdev_8255_init+0x79/0x8d [comedi_8255]
pci_8255_auto_attach+0x11a/0x139 [8255_pci]
comedi_auto_config+0xac/0x117 [comedi]
? __pfx___driver_attach+0x10/0x10
pci_device_probe+0x88/0xf9
really_probe+0x101/0x248
__driver_probe_device+0xbb/0xed
driver_probe_device+0x1a/0x72
__driver_attach+0xd4/0xed
bus_for_each_dev+0x76/0xb8
bus_add_driver+0xbe/0x1be
driver_register+0x9a/0xd8
comedi_pci_driver_register+0x28/0x48 [comedi_pci]
? __pfx_pci_8255_driver_init+0x10/0x10 [8255_pci]
do_one_initcall+0x72/0x183
do_init_module+0x5b/0x1e8
init_module_from_file+0x86/0xac
__do_sys_finit_module+0x151/0x218
do_syscall_64+0x72/0xdb
entry_SYSCALL_64_after_hwframe+0x6e/0x76
RIP: 0033:0x7f72f50a0cb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 0d 47 71 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffd47e512d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 0000562dd06ae070 RCX: 00007f72f50a0cb9
RDX: 0000000000000000 RSI: 00007f72f52d32df RDI: 000000000000000e
RBP: 0000000000000000 R08: 00007f72f5168b20 R09: 0000000000000000
R10: 0000000000000050 R11: 0000000000000246 R12: 00007f72f52d32df
R13: 0000000000020000 R14: 0000562dd06785c0 R15: 0000562dcfd0e9a8
</TASK>
Modules linked in: 8255_pci(+) comedi_8255 comedi_pci comedi intel_gtt e100(+) acpi_cpufreq rtc_cmos usbhid
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffa3f1c02d7b78 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff91f847aefd00 RCX: 000000000000009b
RDX: 0000000000000003 RSI: 0000000000000001 RDI: ffff91f840f6fc00
RBP: ffff91f840f6fc00 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 000000000000005f R12: 0000000000000000
R13: 0000000000000000 R14: ffffffffc0102498 R15: ffff91f847ce6ba8
FS:
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw89: pci: validate sequence number of TX release report
Hardware rarely reports abnormal sequence number in TX release report,
which will access out-of-bounds of wd_ring->pages array, causing NULL
pointer dereference.
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 1085 Comm: irq/129-rtw89_p Tainted: G S U
6.1.145-17510-g2f3369c91536 #1 (HASH:69e8 1)
Call Trace:
<IRQ>
rtw89_pci_release_tx+0x18f/0x300 [rtw89_pci (HASH:4c83 2)]
rtw89_pci_napi_poll+0xc2/0x190 [rtw89_pci (HASH:4c83 2)]
net_rx_action+0xfc/0x460 net/core/dev.c:6578 net/core/dev.c:6645 net/core/dev.c:6759
handle_softirqs+0xbe/0x290 kernel/softirq.c:601
? rtw89_pci_interrupt_threadfn+0xc5/0x350 [rtw89_pci (HASH:4c83 2)]
__local_bh_enable_ip+0xeb/0x120 kernel/softirq.c:499 kernel/softirq.c:423
</IRQ>
<TASK>
rtw89_pci_interrupt_threadfn+0xf8/0x350 [rtw89_pci (HASH:4c83 2)]
? irq_thread+0xa7/0x340 kernel/irq/manage.c:0
irq_thread+0x177/0x340 kernel/irq/manage.c:1205 kernel/irq/manage.c:1314
? thaw_kernel_threads+0xb0/0xb0 kernel/irq/manage.c:1202
? irq_forced_thread_fn+0x80/0x80 kernel/irq/manage.c:1220
kthread+0xea/0x110 kernel/kthread.c:376
? synchronize_irq+0x1a0/0x1a0 kernel/irq/manage.c:1287
? kthread_associate_blkcg+0x80/0x80 kernel/kthread.c:331
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
To prevent crash, validate rpp_info.seq before using. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/ttm: fix bulk_move corruption when adding a entry
When the resource is the first in the bulk_move range, adding it again
(thus moving it to the tail) will corrupt the list since the first
pointer is not moved. This eventually lead to null pointer deref in
ttm_lru_bulk_move_del() |
| In the Linux kernel, the following vulnerability has been resolved:
ice: Block switchdev mode when ADQ is active and vice versa
ADQ and switchdev are not supported simultaneously. Enabling both at the
same time can result in nullptr dereference.
To prevent this, check if ADQ is active when changing devlink mode to
switchdev mode, and check if switchdev is active when enabling ADQ. |
| In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix sysfs interface lifetime
The current nilfs2 sysfs support has issues with the timing of creation
and deletion of sysfs entries, potentially leading to null pointer
dereferences, use-after-free, and lockdep warnings.
Some of the sysfs attributes for nilfs2 per-filesystem instance refer to
metadata file "cpfile", "sufile", or "dat", but
nilfs_sysfs_create_device_group that creates those attributes is executed
before the inodes for these metadata files are loaded, and
nilfs_sysfs_delete_device_group which deletes these sysfs entries is
called after releasing their metadata file inodes.
Therefore, access to some of these sysfs attributes may occur outside of
the lifetime of these metadata files, resulting in inode NULL pointer
dereferences or use-after-free.
In addition, the call to nilfs_sysfs_create_device_group() is made during
the locking period of the semaphore "ns_sem" of nilfs object, so the
shrinker call caused by the memory allocation for the sysfs entries, may
derive lock dependencies "ns_sem" -> (shrinker) -> "locks acquired in
nilfs_evict_inode()".
Since nilfs2 may acquire "ns_sem" deep in the call stack holding other
locks via its error handler __nilfs_error(), this causes lockdep to report
circular locking. This is a false positive and no circular locking
actually occurs as no inodes exist yet when
nilfs_sysfs_create_device_group() is called. Fortunately, the lockdep
warnings can be resolved by simply moving the call to
nilfs_sysfs_create_device_group() out of "ns_sem".
This fixes these sysfs issues by revising where the device's sysfs
interface is created/deleted and keeping its lifetime within the lifetime
of the metadata files above. |