| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda/hdmi: Fix breakage at probing nvhdmi-mcp driver
After restructuring and splitting the HDMI codec driver code, each
HDMI codec driver contains the own build_controls and build_pcms ops.
A copy-n-paste error put the wrong entries for nvhdmi-mcp driver; both
build_controls and build_pcms are swapped. Unfortunately both
callbacks have the very same form, and the compiler didn't complain
it, either. This resulted in a NULL dereference because the PCM
instance hasn't been initialized at calling the build_controls
callback.
Fix it by passing the proper entries. |
| In the Linux kernel, the following vulnerability has been resolved:
mlx5: Fix default values in create CQ
Currently, CQs without a completion function are assigned the
mlx5_add_cq_to_tasklet function by default. This is problematic since
only user CQs created through the mlx5_ib driver are intended to use
this function.
Additionally, all CQs that will use doorbells instead of polling for
completions must call mlx5_cq_arm. However, the default CQ creation flow
leaves a valid value in the CQ's arm_db field, allowing FW to send
interrupts to polling-only CQs in certain corner cases.
These two factors would allow a polling-only kernel CQ to be triggered
by an EQ interrupt and call a completion function intended only for user
CQs, causing a null pointer exception.
Some areas in the driver have prevented this issue with one-off fixes
but did not address the root cause.
This patch fixes the described issue by adding defaults to the create CQ
flow. It adds a default dummy completion function to protect against
null pointer exceptions, and it sets an invalid command sequence number
by default in kernel CQs to prevent the FW from sending an interrupt to
the CQ until it is armed. User CQs are responsible for their own
initialization values.
Callers of mlx5_core_create_cq are responsible for changing the
completion function and arming the CQ per their needs. |
| In the Linux kernel, the following vulnerability has been resolved:
erofs: avoid infinite loop due to incomplete zstd-compressed data
Currently, the decompression logic incorrectly spins if compressed
data is truncated in crafted (deliberately corrupted) images. |
| In the Linux kernel, the following vulnerability has been resolved:
fs: Fix uninitialized 'offp' in statmount_string()
In statmount_string(), most flags assign an output offset pointer (offp)
which is later updated with the string offset. However, the
STATMOUNT_MNT_UIDMAP and STATMOUNT_MNT_GIDMAP cases directly set the
struct fields instead of using offp. This leaves offp uninitialized,
leading to a possible uninitialized dereference when *offp is updated.
Fix it by assigning offp for UIDMAP and GIDMAP as well, keeping the code
path consistent. |
| In the Linux kernel, the following vulnerability has been resolved:
ice: fix PTP cleanup on driver removal in error path
Improve the cleanup on releasing PTP resources in error path.
The error case might happen either at the driver probe and PTP
feature initialization or on PTP restart (errors in reset handling, NVM
update etc). In both cases, calls to PF PTP cleanup (ice_ptp_cleanup_pf
function) and 'ps_lock' mutex deinitialization were missed.
Additionally, ptp clock was not unregistered in the latter case.
Keep PTP state as 'uninitialized' on init to distinguish between error
scenarios and to avoid resource release duplication at driver removal.
The consequence of missing ice_ptp_cleanup_pf call is the following call
trace dumped when ice_adapter object is freed (port list is not empty,
as it is required at this stage):
[ T93022] ------------[ cut here ]------------
[ T93022] WARNING: CPU: 10 PID: 93022 at
ice/ice_adapter.c:67 ice_adapter_put+0xef/0x100 [ice]
...
[ T93022] RIP: 0010:ice_adapter_put+0xef/0x100 [ice]
...
[ T93022] Call Trace:
[ T93022] <TASK>
[ T93022] ? ice_adapter_put+0xef/0x100 [ice
33d2647ad4f6d866d41eefff1806df37c68aef0c]
[ T93022] ? __warn.cold+0xb0/0x10e
[ T93022] ? ice_adapter_put+0xef/0x100 [ice
33d2647ad4f6d866d41eefff1806df37c68aef0c]
[ T93022] ? report_bug+0xd8/0x150
[ T93022] ? handle_bug+0xe9/0x110
[ T93022] ? exc_invalid_op+0x17/0x70
[ T93022] ? asm_exc_invalid_op+0x1a/0x20
[ T93022] ? ice_adapter_put+0xef/0x100 [ice
33d2647ad4f6d866d41eefff1806df37c68aef0c]
[ T93022] pci_device_remove+0x42/0xb0
[ T93022] device_release_driver_internal+0x19f/0x200
[ T93022] driver_detach+0x48/0x90
[ T93022] bus_remove_driver+0x70/0xf0
[ T93022] pci_unregister_driver+0x42/0xb0
[ T93022] ice_module_exit+0x10/0xdb0 [ice
33d2647ad4f6d866d41eefff1806df37c68aef0c]
...
[ T93022] ---[ end trace 0000000000000000 ]---
[ T93022] ice: module unloaded |
| In the Linux kernel, the following vulnerability has been resolved:
LoongArch: BPF: Disable trampoline for kernel module function trace
The current LoongArch BPF trampoline implementation is incompatible
with tracing functions in kernel modules. This causes several severe
and user-visible problems:
* The `bpf_selftests/module_attach` test fails consistently.
* Kernel lockup when a BPF program is attached to a module function [1].
* Critical kernel modules like WireGuard experience traffic disruption
when their functions are traced with fentry [2].
Given the severity and the potential for other unknown side-effects, it
is safest to disable the feature entirely for now. This patch prevents
the BPF subsystem from allowing trampoline attachments to kernel module
functions on LoongArch.
This is a temporary mitigation until the core issues in the trampoline
code for kernel module handling can be identified and fixed.
[root@fedora bpf]# ./test_progs -a module_attach -v
bpf_testmod.ko is already unloaded.
Loading bpf_testmod.ko...
Successfully loaded bpf_testmod.ko.
test_module_attach:PASS:skel_open 0 nsec
test_module_attach:PASS:set_attach_target 0 nsec
test_module_attach:PASS:set_attach_target_explicit 0 nsec
test_module_attach:PASS:skel_load 0 nsec
libbpf: prog 'handle_fentry': failed to attach: -ENOTSUPP
libbpf: prog 'handle_fentry': failed to auto-attach: -ENOTSUPP
test_module_attach:FAIL:skel_attach skeleton attach failed: -524
Summary: 0/0 PASSED, 0 SKIPPED, 1 FAILED
Successfully unloaded bpf_testmod.ko.
[1]: https://lore.kernel.org/loongarch/CAK3+h2wDmpC-hP4u4pJY8T-yfKyk4yRzpu2LMO+C13FMT58oqQ@mail.gmail.com/
[2]: https://lore.kernel.org/loongarch/CAK3+h2wYcpc+OwdLDUBvg2rF9rvvyc5amfHT-KcFaK93uoELPg@mail.gmail.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
cifs: fix memory leak in smb3_fs_context_parse_param error path
Add proper cleanup of ctx->source and fc->source to the
cifs_parse_mount_err error handler. This ensures that memory allocated
for the source strings is correctly freed on all error paths, matching
the cleanup already performed in the success path by
smb3_cleanup_fs_context_contents().
Pointers are also set to NULL after freeing to prevent potential
double-free issues.
This change fixes a memory leak originally detected by syzbot. The
leak occurred when processing Opt_source mount options if an error
happened after ctx->source and fc->source were successfully
allocated but before the function completed.
The specific leak sequence was:
1. ctx->source = smb3_fs_context_fullpath(ctx, '/') allocates memory
2. fc->source = kstrdup(ctx->source, GFP_KERNEL) allocates more memory
3. A subsequent error jumps to cifs_parse_mount_err
4. The old error handler freed passwords but not the source strings,
causing the memory to leak.
This issue was not addressed by commit e8c73eb7db0a ("cifs: client:
fix memory leak in smb3_fs_context_parse_param"), which only fixed
leaks from repeated fsconfig() calls but not this error path.
Patch updated with minor change suggested by kernel test robot |
| In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: ti: netcp: Standardize knav_dma_open_channel to return NULL on error
Make knav_dma_open_channel consistently return NULL on error instead
of ERR_PTR. Currently the header include/linux/soc/ti/knav_dma.h
returns NULL when the driver is disabled, but the driver
implementation does not even return NULL or ERR_PTR on failure,
causing inconsistency in the users. This results in a crash in
netcp_free_navigator_resources as followed (trimmed):
Unhandled fault: alignment exception (0x221) at 0xfffffff2
[fffffff2] *pgd=80000800207003, *pmd=82ffda003, *pte=00000000
Internal error: : 221 [#1] SMP ARM
Modules linked in:
CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.17.0-rc7 #1 NONE
Hardware name: Keystone
PC is at knav_dma_close_channel+0x30/0x19c
LR is at netcp_free_navigator_resources+0x2c/0x28c
[... TRIM...]
Call trace:
knav_dma_close_channel from netcp_free_navigator_resources+0x2c/0x28c
netcp_free_navigator_resources from netcp_ndo_open+0x430/0x46c
netcp_ndo_open from __dev_open+0x114/0x29c
__dev_open from __dev_change_flags+0x190/0x208
__dev_change_flags from netif_change_flags+0x1c/0x58
netif_change_flags from dev_change_flags+0x38/0xa0
dev_change_flags from ip_auto_config+0x2c4/0x11f0
ip_auto_config from do_one_initcall+0x58/0x200
do_one_initcall from kernel_init_freeable+0x1cc/0x238
kernel_init_freeable from kernel_init+0x1c/0x12c
kernel_init from ret_from_fork+0x14/0x38
[... TRIM...]
Standardize the error handling by making the function return NULL on
all error conditions. The API is used in just the netcp_core.c so the
impact is limited.
Note, this change, in effect reverts commit 5b6cb43b4d62 ("net:
ethernet: ti: netcp_core: return error while dma channel open issue"),
but provides a less error prone implementation. |
| In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Fix unsafe locking in the scx_dump_state()
For built with CONFIG_PREEMPT_RT=y kernels, the dump_lock will be converted
sleepable spinlock and not disable-irq, so the following scenarios occur:
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
irq_work/0/27 [HC0[0]:SC0[0]:HE1:SE1] takes:
(&rq->__lock){?...}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x40
{IN-HARDIRQ-W} state was registered at:
lock_acquire+0x1e1/0x510
_raw_spin_lock_nested+0x42/0x80
raw_spin_rq_lock_nested+0x2b/0x40
sched_tick+0xae/0x7b0
update_process_times+0x14c/0x1b0
tick_periodic+0x62/0x1f0
tick_handle_periodic+0x48/0xf0
timer_interrupt+0x55/0x80
__handle_irq_event_percpu+0x20a/0x5c0
handle_irq_event_percpu+0x18/0xc0
handle_irq_event+0xb5/0x150
handle_level_irq+0x220/0x460
__common_interrupt+0xa2/0x1e0
common_interrupt+0xb0/0xd0
asm_common_interrupt+0x2b/0x40
_raw_spin_unlock_irqrestore+0x45/0x80
__setup_irq+0xc34/0x1a30
request_threaded_irq+0x214/0x2f0
hpet_time_init+0x3e/0x60
x86_late_time_init+0x5b/0xb0
start_kernel+0x308/0x410
x86_64_start_reservations+0x1c/0x30
x86_64_start_kernel+0x96/0xa0
common_startup_64+0x13e/0x148
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&rq->__lock);
<Interrupt>
lock(&rq->__lock);
*** DEADLOCK ***
stack backtrace:
CPU: 0 UID: 0 PID: 27 Comm: irq_work/0
Call Trace:
<TASK>
dump_stack_lvl+0x8c/0xd0
dump_stack+0x14/0x20
print_usage_bug+0x42e/0x690
mark_lock.part.44+0x867/0xa70
? __pfx_mark_lock.part.44+0x10/0x10
? string_nocheck+0x19c/0x310
? number+0x739/0x9f0
? __pfx_string_nocheck+0x10/0x10
? __pfx_check_pointer+0x10/0x10
? kvm_sched_clock_read+0x15/0x30
? sched_clock_noinstr+0xd/0x20
? local_clock_noinstr+0x1c/0xe0
__lock_acquire+0xc4b/0x62b0
? __pfx_format_decode+0x10/0x10
? __pfx_string+0x10/0x10
? __pfx___lock_acquire+0x10/0x10
? __pfx_vsnprintf+0x10/0x10
lock_acquire+0x1e1/0x510
? raw_spin_rq_lock_nested+0x2b/0x40
? __pfx_lock_acquire+0x10/0x10
? dump_line+0x12e/0x270
? raw_spin_rq_lock_nested+0x20/0x40
_raw_spin_lock_nested+0x42/0x80
? raw_spin_rq_lock_nested+0x2b/0x40
raw_spin_rq_lock_nested+0x2b/0x40
scx_dump_state+0x3b3/0x1270
? finish_task_switch+0x27e/0x840
scx_ops_error_irq_workfn+0x67/0x80
irq_work_single+0x113/0x260
irq_work_run_list.part.3+0x44/0x70
run_irq_workd+0x6b/0x90
? __pfx_run_irq_workd+0x10/0x10
smpboot_thread_fn+0x529/0x870
? __pfx_smpboot_thread_fn+0x10/0x10
kthread+0x305/0x3f0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x40/0x70
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
This commit therefore use rq_lock_irqsave/irqrestore() to replace
rq_lock/unlock() in the scx_dump_state(). |
| In the Linux kernel, the following vulnerability has been resolved:
drm: Fix potential null-ptr-deref due to drmm_mode_config_init()
drmm_mode_config_init() will call drm_mode_create_standard_properties()
and won't check the ret value. When drm_mode_create_standard_properties()
failed due to alloc, property will be a NULL pointer and may causes the
null-ptr-deref. Fix the null-ptr-deref by adding the ret value check.
Found null-ptr-deref while testing insert module bochs:
general protection fault, probably for non-canonical address
0xdffffc000000000c: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]
CPU: 3 PID: 249 Comm: modprobe Not tainted 6.1.0-rc1+ #364
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
RIP: 0010:drm_object_attach_property+0x73/0x3c0 [drm]
Call Trace:
<TASK>
__drm_connector_init+0xb6c/0x1100 [drm]
bochs_pci_probe.cold.11+0x4cb/0x7fe [bochs]
pci_device_probe+0x17d/0x340
really_probe+0x1db/0x5d0
__driver_probe_device+0x1e7/0x250
driver_probe_device+0x4a/0x120
__driver_attach+0xcd/0x2c0
bus_for_each_dev+0x11a/0x1b0
bus_add_driver+0x3d7/0x500
driver_register+0x18e/0x320
do_one_initcall+0xc4/0x3e0
do_init_module+0x1b4/0x630
load_module+0x5dca/0x7230
__do_sys_finit_module+0x100/0x170
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ff65af9f839 |
| In the Linux kernel, the following vulnerability has been resolved:
regmap-irq: Use the new num_config_regs property in regmap_add_irq_chip_fwnode
Commit faa87ce9196d ("regmap-irq: Introduce config registers for irq
types") added the num_config_regs, then commit 9edd4f5aee84 ("regmap-irq:
Deprecate type registers and virtual registers") suggested to replace
num_type_reg with it. However, regmap_add_irq_chip_fwnode wasn't modified
to use the new property. Later on, commit 255a03bb1bb3 ("ASoC: wcd9335:
Convert irq chip to config regs") removed the old num_type_reg property
from the WCD9335 driver's struct regmap_irq_chip, causing a null pointer
dereference in regmap_irq_set_type when it tried to index d->type_buf as
it was never allocated in regmap_add_irq_chip_fwnode:
[ 39.199374] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[ 39.200006] Call trace:
[ 39.200014] regmap_irq_set_type+0x84/0x1c0
[ 39.200026] __irq_set_trigger+0x60/0x1c0
[ 39.200040] __setup_irq+0x2f4/0x78c
[ 39.200051] request_threaded_irq+0xe8/0x1a0
Use num_config_regs in regmap_add_irq_chip_fwnode instead of num_type_reg,
and fall back to it if num_config_regs isn't defined to maintain backward
compatibility. |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: qmi_wwan: initialize MAC header offset in qmimux_rx_fixup
Raw IP packets have no MAC header, leaving skb->mac_header uninitialized.
This can trigger kernel panics on ARM64 when xfrm or other subsystems
access the offset due to strict alignment checks.
Initialize the MAC header to prevent such crashes.
This can trigger kernel panics on ARM when running IPsec over the
qmimux0 interface.
Example trace:
Internal error: Oops: 000000009600004f [#1] SMP
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.34-gbe78e49cb433 #1
Hardware name: LS1028A RDB Board (DT)
pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : xfrm_input+0xde8/0x1318
lr : xfrm_input+0x61c/0x1318
sp : ffff800080003b20
Call trace:
xfrm_input+0xde8/0x1318
xfrm6_rcv+0x38/0x44
xfrm6_esp_rcv+0x48/0xa8
ip6_protocol_deliver_rcu+0x94/0x4b0
ip6_input_finish+0x44/0x70
ip6_input+0x44/0xc0
ipv6_rcv+0x6c/0x114
__netif_receive_skb_one_core+0x5c/0x8c
__netif_receive_skb+0x18/0x60
process_backlog+0x78/0x17c
__napi_poll+0x38/0x180
net_rx_action+0x168/0x2f0 |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Add bpf_prog_run_data_pointers()
syzbot found that cls_bpf_classify() is able to change
tc_skb_cb(skb)->drop_reason triggering a warning in sk_skb_reason_drop().
WARNING: CPU: 0 PID: 5965 at net/core/skbuff.c:1192 __sk_skb_reason_drop net/core/skbuff.c:1189 [inline]
WARNING: CPU: 0 PID: 5965 at net/core/skbuff.c:1192 sk_skb_reason_drop+0x76/0x170 net/core/skbuff.c:1214
struct tc_skb_cb has been added in commit ec624fe740b4 ("net/sched:
Extend qdisc control block with tc control block"), which added a wrong
interaction with db58ba459202 ("bpf: wire in data and data_end for
cls_act_bpf").
drop_reason was added later.
Add bpf_prog_run_data_pointers() helper to save/restore the net_sched
storage colliding with BPF data_meta/data_end. |
| In the Linux kernel, the following vulnerability has been resolved:
udp_tunnel: use netdev_warn() instead of netdev_WARN()
netdev_WARN() uses WARN/WARN_ON to print a backtrace along with
file and line information. In this case, udp_tunnel_nic_register()
returning an error is just a failed operation, not a kernel bug.
udp_tunnel_nic_register() can fail due to a memory allocation
failure (kzalloc() or udp_tunnel_nic_alloc()).
This is a normal runtime error and not a kernel bug.
Replace netdev_WARN() with netdev_warn() accordingly. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/msm: Fix GEM free for imported dma-bufs
Imported dma-bufs also have obj->resv != &obj->_resv. So we should
check both this condition in addition to flags for handling the
_NO_SHARE case.
Fixes this splat that was reported with IRIS video playback:
------------[ cut here ]------------
WARNING: CPU: 3 PID: 2040 at drivers/gpu/drm/msm/msm_gem.c:1127 msm_gem_free_object+0x1f8/0x264 [msm]
CPU: 3 UID: 1000 PID: 2040 Comm: .gnome-shell-wr Not tainted 6.17.0-rc7 #1 PREEMPT
pstate: 81400005 (Nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : msm_gem_free_object+0x1f8/0x264 [msm]
lr : msm_gem_free_object+0x138/0x264 [msm]
sp : ffff800092a1bb30
x29: ffff800092a1bb80 x28: ffff800092a1bce8 x27: ffffbc702dbdbe08
x26: 0000000000000008 x25: 0000000000000009 x24: 00000000000000a6
x23: ffff00083c72f850 x22: ffff00083c72f868 x21: ffff00087e69f200
x20: ffff00087e69f330 x19: ffff00084d157ae0 x18: 0000000000000000
x17: 0000000000000000 x16: ffffbc704bd46b80 x15: 0000ffffd0959540
x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
x11: ffffbc702e6cdb48 x10: 0000000000000000 x9 : 000000000000003f
x8 : ffff800092a1ba90 x7 : 0000000000000000 x6 : 0000000000000020
x5 : ffffbc704bd46c40 x4 : fffffdffe102cf60 x3 : 0000000000400032
x2 : 0000000000020000 x1 : ffff00087e6978e8 x0 : ffff00087e6977e8
Call trace:
msm_gem_free_object+0x1f8/0x264 [msm] (P)
drm_gem_object_free+0x1c/0x30 [drm]
drm_gem_object_handle_put_unlocked+0x138/0x150 [drm]
drm_gem_object_release_handle+0x5c/0xcc [drm]
drm_gem_handle_delete+0x68/0xbc [drm]
drm_gem_close_ioctl+0x34/0x40 [drm]
drm_ioctl_kernel+0xc0/0x130 [drm]
drm_ioctl+0x360/0x4e0 [drm]
__arm64_sys_ioctl+0xac/0x104
invoke_syscall+0x48/0x104
el0_svc_common.constprop.0+0x40/0xe0
do_el0_svc+0x1c/0x28
el0_svc+0x34/0xec
el0t_64_sync_handler+0xa0/0xe4
el0t_64_sync+0x198/0x19c
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
Patchwork: https://patchwork.freedesktop.org/patch/676273/ |
| In the Linux kernel, the following vulnerability has been resolved:
tcp: use dst_dev_rcu() in tcp_fastopen_active_disable_ofo_check()
Use RCU to avoid a pair of atomic operations and a potential
UAF on dst_dev()->flags. |
| In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Do not warn in ring_buffer_map_get_reader() when reader catches up
The function ring_buffer_map_get_reader() is a bit more strict than the
other get reader functions, and except for certain situations the
rb_get_reader_page() should not return NULL. If it does, it triggers a
warning.
This warning was triggering but after looking at why, it was because
another acceptable situation was happening and it wasn't checked for.
If the reader catches up to the writer and there's still data to be read
on the reader page, then the rb_get_reader_page() will return NULL as
there's no new page to get.
In this situation, the reader page should not be updated and no warning
should trigger. |
| URL Redirection to Untrusted Site ('Open Redirect') vulnerability in Bunkerity Bunker Web on Linux allows Phishing.This issue affects Bunker Web: 1.6.2. |
| The llama-index-core package, up to version 0.12.44, contains a vulnerability in the `get_cache_dir()` function where a predictable, hardcoded directory path `/tmp/llama_index` is used on Linux systems without proper security controls. This vulnerability allows attackers on multi-user systems to steal proprietary models, poison cached embeddings, or conduct symlink attacks. The issue affects all Linux deployments where multiple users share the same system. The vulnerability is classified under CWE-379, CWE-377, and CWE-367, indicating insecure temporary file creation and potential race conditions. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix deadlock in wait_current_trans() due to ignored transaction type
When wait_current_trans() is called during start_transaction(), it
currently waits for a blocked transaction without considering whether
the given transaction type actually needs to wait for that particular
transaction state. The btrfs_blocked_trans_types[] array already defines
which transaction types should wait for which transaction states, but
this check was missing in wait_current_trans().
This can lead to a deadlock scenario involving two transactions and
pending ordered extents:
1. Transaction A is in TRANS_STATE_COMMIT_DOING state
2. A worker processing an ordered extent calls start_transaction()
with TRANS_JOIN
3. join_transaction() returns -EBUSY because Transaction A is in
TRANS_STATE_COMMIT_DOING
4. Transaction A moves to TRANS_STATE_UNBLOCKED and completes
5. A new Transaction B is created (TRANS_STATE_RUNNING)
6. The ordered extent from step 2 is added to Transaction B's
pending ordered extents
7. Transaction B immediately starts commit by another task and
enters TRANS_STATE_COMMIT_START
8. The worker finally reaches wait_current_trans(), sees Transaction B
in TRANS_STATE_COMMIT_START (a blocked state), and waits
unconditionally
9. However, TRANS_JOIN should NOT wait for TRANS_STATE_COMMIT_START
according to btrfs_blocked_trans_types[]
10. Transaction B is waiting for pending ordered extents to complete
11. Deadlock: Transaction B waits for ordered extent, ordered extent
waits for Transaction B
This can be illustrated by the following call stacks:
CPU0 CPU1
btrfs_finish_ordered_io()
start_transaction(TRANS_JOIN)
join_transaction()
# -EBUSY (Transaction A is
# TRANS_STATE_COMMIT_DOING)
# Transaction A completes
# Transaction B created
# ordered extent added to
# Transaction B's pending list
btrfs_commit_transaction()
# Transaction B enters
# TRANS_STATE_COMMIT_START
# waiting for pending ordered
# extents
wait_current_trans()
# waits for Transaction B
# (should not wait!)
Task bstore_kv_sync in btrfs_commit_transaction waiting for ordered
extents:
__schedule+0x2e7/0x8a0
schedule+0x64/0xe0
btrfs_commit_transaction+0xbf7/0xda0 [btrfs]
btrfs_sync_file+0x342/0x4d0 [btrfs]
__x64_sys_fdatasync+0x4b/0x80
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Task kworker in wait_current_trans waiting for transaction commit:
Workqueue: btrfs-syno_nocow btrfs_work_helper [btrfs]
__schedule+0x2e7/0x8a0
schedule+0x64/0xe0
wait_current_trans+0xb0/0x110 [btrfs]
start_transaction+0x346/0x5b0 [btrfs]
btrfs_finish_ordered_io.isra.0+0x49b/0x9c0 [btrfs]
btrfs_work_helper+0xe8/0x350 [btrfs]
process_one_work+0x1d3/0x3c0
worker_thread+0x4d/0x3e0
kthread+0x12d/0x150
ret_from_fork+0x1f/0x30
Fix this by passing the transaction type to wait_current_trans() and
checking btrfs_blocked_trans_types[cur_trans->state] against the given
type before deciding to wait. This ensures that transaction types which
are allowed to join during certain blocked states will not unnecessarily
wait and cause deadlocks. |