| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
nvme-fc: release admin tagset if init fails
nvme_fabrics creates an NVMe/FC controller in following path:
nvmf_dev_write()
-> nvmf_create_ctrl()
-> nvme_fc_create_ctrl()
-> nvme_fc_init_ctrl()
nvme_fc_init_ctrl() allocates the admin blk-mq resources right after
nvme_add_ctrl() succeeds. If any of the subsequent steps fail (changing
the controller state, scheduling connect work, etc.), we jump to the
fail_ctrl path, which tears down the controller references but never
frees the admin queue/tag set. The leaked blk-mq allocations match the
kmemleak report seen during blktests nvme/fc.
Check ctrl->ctrl.admin_tagset in the fail_ctrl path and call
nvme_remove_admin_tag_set() when it is set so that all admin queue
allocations are reclaimed whenever controller setup aborts. |
| In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Enable exception fixup for specific ADE subcode
This patch allows the LoongArch BPF JIT to handle recoverable memory
access errors generated by BPF_PROBE_MEM* instructions.
When a BPF program performs memory access operations, the instructions
it executes may trigger ADEM exceptions. The kernel’s built-in BPF
exception table mechanism (EX_TYPE_BPF) will generate corresponding
exception fixup entries in the JIT compilation phase; however, the
architecture-specific trap handling function needs to proactively call
the common fixup routine to achieve exception recovery.
do_ade(): fix EX_TYPE_BPF memory access exceptions for BPF programs,
ensure safe execution.
Relevant test cases: illegal address access tests in module_attach and
subprogs_extable of selftests/bpf. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: Don't clobber irqfd routing type when deassigning irqfd
When deassigning a KVM_IRQFD, don't clobber the irqfd's copy of the IRQ's
routing entry as doing so breaks kvm_arch_irq_bypass_del_producer() on x86
and arm64, which explicitly look for KVM_IRQ_ROUTING_MSI. Instead, to
handle a concurrent routing update, verify that the irqfd is still active
before consuming the routing information. As evidenced by the x86 and
arm64 bugs, and another bug in kvm_arch_update_irqfd_routing() (see below),
clobbering the entry type without notifying arch code is surprising and
error prone.
As a bonus, checking that the irqfd is active provides a convenient
location for documenting _why_ KVM must not consume the routing entry for
an irqfd that is in the process of being deassigned: once the irqfd is
deleted from the list (which happens *before* the eventfd is detached), it
will no longer receive updates via kvm_irq_routing_update(), and so KVM
could deliver an event using stale routing information (relative to
KVM_SET_GSI_ROUTING returning to userspace).
As an even better bonus, explicitly checking for the irqfd being active
fixes a similar bug to the one the clobbering is trying to prevent: if an
irqfd is deactivated, and then its routing is changed,
kvm_irq_routing_update() won't invoke kvm_arch_update_irqfd_routing()
(because the irqfd isn't in the list). And so if the irqfd is in bypass
mode, IRQs will continue to be posted using the old routing information.
As for kvm_arch_irq_bypass_del_producer(), clobbering the routing type
results in KVM incorrectly keeping the IRQ in bypass mode, which is
especially problematic on AMD as KVM tracks IRQs that are being posted to
a vCPU in a list whose lifetime is tied to the irqfd.
Without the help of KASAN to detect use-after-free, the most common
sympton on AMD is a NULL pointer deref in amd_iommu_update_ga() due to
the memory for irqfd structure being re-allocated and zeroed, resulting
in irqfd->irq_bypass_data being NULL when read by
avic_update_iommu_vcpu_affinity():
BUG: kernel NULL pointer dereference, address: 0000000000000018
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 40cf2b9067 P4D 40cf2b9067 PUD 408362a067 PMD 0
Oops: Oops: 0000 [#1] SMP
CPU: 6 UID: 0 PID: 40383 Comm: vfio_irq_test
Tainted: G U W O 6.19.0-smp--5dddc257e6b2-irqfd #31 NONE
Tainted: [U]=USER, [W]=WARN, [O]=OOT_MODULE
Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 34.78.2-0 09/05/2025
RIP: 0010:amd_iommu_update_ga+0x19/0xe0
Call Trace:
<TASK>
avic_update_iommu_vcpu_affinity+0x3d/0x90 [kvm_amd]
__avic_vcpu_load+0xf4/0x130 [kvm_amd]
kvm_arch_vcpu_load+0x89/0x210 [kvm]
vcpu_load+0x30/0x40 [kvm]
kvm_arch_vcpu_ioctl_run+0x45/0x620 [kvm]
kvm_vcpu_ioctl+0x571/0x6a0 [kvm]
__se_sys_ioctl+0x6d/0xb0
do_syscall_64+0x6f/0x9d0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x46893b
</TASK>
---[ end trace 0000000000000000 ]---
If AVIC is inhibited when the irfd is deassigned, the bug will manifest as
list corruption, e.g. on the next irqfd assignment.
list_add corruption. next->prev should be prev (ffff8d474d5cd588),
but was 0000000000000000. (next=ffff8d8658f86530).
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:31!
Oops: invalid opcode: 0000 [#1] SMP
CPU: 128 UID: 0 PID: 80818 Comm: vfio_irq_test
Tainted: G U W O 6.19.0-smp--f19dc4d680ba-irqfd #28 NONE
Tainted: [U]=USER, [W]=WARN, [O]=OOT_MODULE
Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 34.78.2-0 09/05/2025
RIP: 0010:__list_add_valid_or_report+0x97/0xc0
Call Trace:
<TASK>
avic_pi_update_irte+0x28e/0x2b0 [kvm_amd]
kvm_pi_update_irte+0xbf/0x190 [kvm]
kvm_arch_irq_bypass_add_producer+0x72/0x90 [kvm]
irq_bypass_register_consumer+0xcd/0x170 [irqbypa
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
procfs: avoid fetching build ID while holding VMA lock
Fix PROCMAP_QUERY to fetch optional build ID only after dropping mmap_lock
or per-VMA lock, whichever was used to lock VMA under question, to avoid
deadlock reported by syzbot:
-> #1 (&mm->mmap_lock){++++}-{4:4}:
__might_fault+0xed/0x170
_copy_to_iter+0x118/0x1720
copy_page_to_iter+0x12d/0x1e0
filemap_read+0x720/0x10a0
blkdev_read_iter+0x2b5/0x4e0
vfs_read+0x7f4/0xae0
ksys_read+0x12a/0x250
do_syscall_64+0xcb/0xf80
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}:
__lock_acquire+0x1509/0x26d0
lock_acquire+0x185/0x340
down_read+0x98/0x490
blkdev_read_iter+0x2a7/0x4e0
__kernel_read+0x39a/0xa90
freader_fetch+0x1d5/0xa80
__build_id_parse.isra.0+0xea/0x6a0
do_procmap_query+0xd75/0x1050
procfs_procmap_ioctl+0x7a/0xb0
__x64_sys_ioctl+0x18e/0x210
do_syscall_64+0xcb/0xf80
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
rlock(&mm->mmap_lock);
lock(&sb->s_type->i_mutex_key#8);
lock(&mm->mmap_lock);
rlock(&sb->s_type->i_mutex_key#8);
*** DEADLOCK ***
This seems to be exacerbated (as we haven't seen these syzbot reports
before that) by the recent:
777a8560fd29 ("lib/buildid: use __kernel_read() for sleepable context")
To make this safe, we need to grab file refcount while VMA is still locked, but
other than that everything is pretty straightforward. Internal build_id_parse()
API assumes VMA is passed, but it only needs the underlying file reference, so
just add another variant build_id_parse_file() that expects file passed
directly.
[[email protected]: fix up kerneldoc] |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: Fix ECMP sibling count mismatch when clearing RTF_ADDRCONF
syzbot reported a kernel BUG in fib6_add_rt2node() when adding an IPv6
route. [0]
Commit f72514b3c569 ("ipv6: clear RA flags when adding a static
route") introduced logic to clear RTF_ADDRCONF from existing routes
when a static route with the same nexthop is added. However, this
causes a problem when the existing route has a gateway.
When RTF_ADDRCONF is cleared from a route that has a gateway, that
route becomes eligible for ECMP, i.e. rt6_qualify_for_ecmp() returns
true. The issue is that this route was never added to the
fib6_siblings list.
This leads to a mismatch between the following counts:
- The sibling count computed by iterating fib6_next chain, which
includes the newly ECMP-eligible route
- The actual siblings in fib6_siblings list, which does not include
that route
When a subsequent ECMP route is added, fib6_add_rt2node() hits
BUG_ON(sibling->fib6_nsiblings != rt->fib6_nsiblings) because the
counts don't match.
Fix this by only clearing RTF_ADDRCONF when the existing route does
not have a gateway. Routes without a gateway cannot qualify for ECMP
anyway (rt6_qualify_for_ecmp() requires fib_nh_gw_family), so clearing
RTF_ADDRCONF on them is safe and matches the original intent of the
commit.
[0]:
kernel BUG at net/ipv6/ip6_fib.c:1217!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6010 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:fib6_add_rt2node+0x3433/0x3470 net/ipv6/ip6_fib.c:1217
[...]
Call Trace:
<TASK>
fib6_add+0x8da/0x18a0 net/ipv6/ip6_fib.c:1532
__ip6_ins_rt net/ipv6/route.c:1351 [inline]
ip6_route_add+0xde/0x1b0 net/ipv6/route.c:3946
ipv6_route_ioctl+0x35c/0x480 net/ipv6/route.c:4571
inet6_ioctl+0x219/0x280 net/ipv6/af_inet6.c:577
sock_do_ioctl+0xdc/0x300 net/socket.c:1245
sock_ioctl+0x576/0x790 net/socket.c:1366
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: fix oops due to invalid pointer for kfree() in parse_longname()
This fixes a kernel oops when reading ceph snapshot directories (.snap),
for example by simply running `ls /mnt/my_ceph/.snap`.
The variable str is guarded by __free(kfree), but advanced by one for
skipping the initial '_' in snapshot names. Thus, kfree() is called
with an invalid pointer. This patch removes the need for advancing the
pointer so kfree() is called with correct memory pointer.
Steps to reproduce:
1. Create snapshots on a cephfs volume (I've 63 snaps in my testcase)
2. Add cephfs mount to fstab
$ echo "[email protected]=/volumes/datapool/stuff/3461082b-ecc9-4e82-8549-3fd2590d3fb6 /mnt/test/stuff ceph acl,noatime,_netdev 0 0" >> /etc/fstab
3. Reboot the system
$ systemctl reboot
4. Check if it's really mounted
$ mount | grep stuff
5. List snapshots (expected 63 snapshots on my system)
$ ls /mnt/test/stuff/.snap
Now ls hangs forever and the kernel log shows the oops. |
| In the Linux kernel, the following vulnerability has been resolved:
spi: tegra210-quad: Protect curr_xfer in tegra_qspi_combined_seq_xfer
The curr_xfer field is read by the IRQ handler without holding the lock
to check if a transfer is in progress. When clearing curr_xfer in the
combined sequence transfer loop, protect it with the spinlock to prevent
a race with the interrupt handler.
Protect the curr_xfer clearing at the exit path of
tegra_qspi_combined_seq_xfer() with the spinlock to prevent a race
with the interrupt handler that reads this field.
Without this protection, the IRQ handler could read a partially updated
curr_xfer value, leading to NULL pointer dereference or use-after-free. |
| In the Linux kernel, the following vulnerability has been resolved:
net: cpsw_new: Execute ndo_set_rx_mode callback in a work queue
Commit 1767bb2d47b7 ("ipv6: mcast: Don't hold RTNL for
IPV6_ADD_MEMBERSHIP and MCAST_JOIN_GROUP.") removed the RTNL lock for
IPV6_ADD_MEMBERSHIP and MCAST_JOIN_GROUP operations. However, this
change triggered the following call trace on my BeagleBone Black board:
WARNING: net/8021q/vlan_core.c:236 at vlan_for_each+0x120/0x124, CPU#0: rpcbind/496
RTNL: assertion failed at net/8021q/vlan_core.c (236)
Modules linked in:
CPU: 0 UID: 997 PID: 496 Comm: rpcbind Not tainted 6.19.0-rc6-next-20260122-yocto-standard+ #8 PREEMPT
Hardware name: Generic AM33XX (Flattened Device Tree)
Call trace:
unwind_backtrace from show_stack+0x28/0x2c
show_stack from dump_stack_lvl+0x30/0x38
dump_stack_lvl from __warn+0xb8/0x11c
__warn from warn_slowpath_fmt+0x130/0x194
warn_slowpath_fmt from vlan_for_each+0x120/0x124
vlan_for_each from cpsw_add_mc_addr+0x54/0xd8
cpsw_add_mc_addr from __hw_addr_ref_sync_dev+0xc4/0xec
__hw_addr_ref_sync_dev from __dev_mc_add+0x78/0x88
__dev_mc_add from igmp6_group_added+0x84/0xec
igmp6_group_added from __ipv6_dev_mc_inc+0x1fc/0x2f0
__ipv6_dev_mc_inc from __ipv6_sock_mc_join+0x124/0x1b4
__ipv6_sock_mc_join from do_ipv6_setsockopt+0x84c/0x1168
do_ipv6_setsockopt from ipv6_setsockopt+0x88/0xc8
ipv6_setsockopt from do_sock_setsockopt+0xe8/0x19c
do_sock_setsockopt from __sys_setsockopt+0x84/0xac
__sys_setsockopt from ret_fast_syscall+0x0/0x5
This trace occurs because vlan_for_each() is called within
cpsw_ndo_set_rx_mode(), which expects the RTNL lock to be held.
Since modifying vlan_for_each() to operate without the RTNL lock is not
straightforward, and because ndo_set_rx_mode() is invoked both with and
without the RTNL lock across different code paths, simply adding
rtnl_lock() in cpsw_ndo_set_rx_mode() is not a viable solution.
To resolve this issue, we opt to execute the actual processing within
a work queue, following the approach used by the icssg-prueth driver. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: cls_u32: use skb_header_pointer_careful()
skb_header_pointer() does not fully validate negative @offset values.
Use skb_header_pointer_careful() instead.
GangMin Kim provided a report and a repro fooling u32_classify():
BUG: KASAN: slab-out-of-bounds in u32_classify+0x1180/0x11b0
net/sched/cls_u32.c:221 |
| In the Linux kernel, the following vulnerability has been resolved:
dpaa2-switch: prevent ZERO_SIZE_PTR dereference when num_ifs is zero
The driver allocates arrays for ports, FDBs, and filter blocks using
kcalloc() with ethsw->sw_attr.num_ifs as the element count. When the
device reports zero interfaces (either due to hardware configuration
or firmware issues), kcalloc(0, ...) returns ZERO_SIZE_PTR (0x10)
instead of NULL.
Later in dpaa2_switch_probe(), the NAPI initialization unconditionally
accesses ethsw->ports[0]->netdev, which attempts to dereference
ZERO_SIZE_PTR (address 0x10), resulting in a kernel panic.
Add a check to ensure num_ifs is greater than zero after retrieving
device attributes. This prevents the zero-sized allocations and
subsequent invalid pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on node footer in {read,write}_end_io
-----------[ cut here ]------------
kernel BUG at fs/f2fs/data.c:358!
Call Trace:
<IRQ>
blk_update_request+0x5eb/0xe70 block/blk-mq.c:987
blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1149
blk_complete_reqs block/blk-mq.c:1224 [inline]
blk_done_softirq+0x107/0x160 block/blk-mq.c:1229
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
</IRQ>
In f2fs_write_end_io(), it detects there is inconsistency in between
node page index (nid) and footer.nid of node page.
If footer of node page is corrupted in fuzzed image, then we load corrupted
node page w/ async method, e.g. f2fs_ra_node_pages() or f2fs_ra_node_page(),
in where we won't do sanity check on node footer, once node page becomes
dirty, we will encounter this bug after node page writeback. |
| In the Linux kernel, the following vulnerability has been resolved:
regmap: maple: free entry on mas_store_gfp() failure
regcache_maple_write() allocates a new block ('entry') to merge
adjacent ranges and then stores it with mas_store_gfp().
When mas_store_gfp() fails, the new 'entry' remains allocated and
is never freed, leaking memory.
Free 'entry' on the failure path; on success continue freeing the
replaced neighbor blocks ('lower', 'upper'). |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring/rw: free potentially allocated iovec on cache put failure
If a read/write request goes through io_req_rw_cleanup() and has an
allocated iovec attached and fails to put to the rw_cache, then it may
end up with an unaccounted iovec pointer. Have io_rw_recycle() return
whether it recycled the request or not, and use that to gauge whether to
free a potential iovec or not. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: do not free data reservation in fallback from inline due to -ENOSPC
If we fail to create an inline extent due to -ENOSPC, we will attempt to
go through the normal COW path, reserve an extent, create an ordered
extent, etc. However we were always freeing the reserved qgroup data,
which is wrong since we will use data. Fix this by freeing the reserved
qgroup data in __cow_file_range_inline() only if we are not doing the
fallback (ret is <= 0). |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix reservation leak in some error paths when inserting inline extent
If we fail to allocate a path or join a transaction, we return from
__cow_file_range_inline() without freeing the reserved qgroup data,
resulting in a leak. Fix this by ensuring we call btrfs_qgroup_free_data()
in such cases. |
| In the Linux kernel, the following vulnerability has been resolved:
net: liquidio: Initialize netdev pointer before queue setup
In setup_nic_devices(), the netdev is allocated using alloc_etherdev_mq().
However, the pointer to this structure is stored in oct->props[i].netdev
only after the calls to netif_set_real_num_rx_queues() and
netif_set_real_num_tx_queues().
If either of these functions fails, setup_nic_devices() returns an error
without freeing the allocated netdev. Since oct->props[i].netdev is still
NULL at this point, the cleanup function liquidio_destroy_nic_device()
will fail to find and free the netdev, resulting in a memory leak.
Fix this by initializing oct->props[i].netdev before calling the queue
setup functions. This ensures that the netdev is properly accessible for
cleanup in case of errors.
Compile tested only. Issue found using a prototype static analysis tool
and code review. |
| In the Linux kernel, the following vulnerability has been resolved:
xfs: check for deleted cursors when revalidating two btrees
The free space and inode btree repair functions will rebuild both btrees
at the same time, after which it needs to evaluate both btrees to
confirm that the corruptions are gone.
However, Jiaming Zhang ran syzbot and produced a crash in the second
xchk_allocbt call. His root-cause analysis is as follows (with minor
corrections):
In xrep_revalidate_allocbt(), xchk_allocbt() is called twice (first
for BNOBT, second for CNTBT). The cause of this issue is that the
first call nullified the cursor required by the second call.
Let's first enter xrep_revalidate_allocbt() via following call chain:
xfs_file_ioctl() ->
xfs_ioc_scrubv_metadata() ->
xfs_scrub_metadata() ->
`sc->ops->repair_eval(sc)` ->
xrep_revalidate_allocbt()
xchk_allocbt() is called twice in this function. In the first call:
/* Note that sc->sm->sm_type is XFS_SCRUB_TYPE_BNOPT now */
xchk_allocbt() ->
xchk_btree() ->
`bs->scrub_rec(bs, recp)` ->
xchk_allocbt_rec() ->
xchk_allocbt_xref() ->
xchk_allocbt_xref_other()
since sm_type is XFS_SCRUB_TYPE_BNOBT, pur is set to &sc->sa.cnt_cur.
Kernel called xfs_alloc_get_rec() and returned -EFSCORRUPTED. Call
chain:
xfs_alloc_get_rec() ->
xfs_btree_get_rec() ->
xfs_btree_check_block() ->
(XFS_IS_CORRUPT || XFS_TEST_ERROR), the former is false and the latter
is true, return -EFSCORRUPTED. This should be caused by
ioctl$XFS_IOC_ERROR_INJECTION I guess.
Back to xchk_allocbt_xref_other(), after receiving -EFSCORRUPTED from
xfs_alloc_get_rec(), kernel called xchk_should_check_xref(). In this
function, *curpp (points to sc->sa.cnt_cur) is nullified.
Back to xrep_revalidate_allocbt(), since sc->sa.cnt_cur has been
nullified, it then triggered null-ptr-deref via xchk_allocbt() (second
call) -> xchk_btree().
So. The bnobt revalidation failed on a cross-reference attempt, so we
deleted the cntbt cursor, and then crashed when we tried to revalidate
the cntbt. Therefore, check for a null cntbt cursor before that
revalidation, and mark the repair incomplete. Also we can ignore the
second tree entirely if the first tree was rebuilt but is already
corrupt.
Apply the same fix to xrep_revalidate_iallocbt because it has the same
problem. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: Only allow act_ct to bind to clsact/ingress qdiscs and shared blocks
As Paolo said earlier [1]:
"Since the blamed commit below, classify can return TC_ACT_CONSUMED while
the current skb being held by the defragmentation engine. As reported by
GangMin Kim, if such packet is that may cause a UaF when the defrag engine
later on tries to tuch again such packet."
act_ct was never meant to be used in the egress path, however some users
are attaching it to egress today [2]. Attempting to reach a middle
ground, we noticed that, while most qdiscs are not handling
TC_ACT_CONSUMED, clsact/ingress qdiscs are. With that in mind, we
address the issue by only allowing act_ct to bind to clsact/ingress
qdiscs and shared blocks. That way it's still possible to attach act_ct to
egress (albeit only with clsact).
[1] https://lore.kernel.org/netdev/674b8cbfc385c6f37fb29a1de08d8fe5c2b0fbee.1771321118.git.pabeni@redhat.com/
[2] https://lore.kernel.org/netdev/[email protected]/ |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix IS_CHECKPOINTED flag inconsistency issue caused by concurrent atomic commit and checkpoint writes
During SPO tests, when mounting F2FS, an -EINVAL error was returned from
f2fs_recover_inode_page. The issue occurred under the following scenario
Thread A Thread B
f2fs_ioc_commit_atomic_write
- f2fs_do_sync_file // atomic = true
- f2fs_fsync_node_pages
: last_folio = inode folio
: schedule before folio_lock(last_folio) f2fs_write_checkpoint
- block_operations// writeback last_folio
- schedule before f2fs_flush_nat_entries
: set_fsync_mark(last_folio, 1)
: set_dentry_mark(last_folio, 1)
: folio_mark_dirty(last_folio)
- __write_node_folio(last_folio)
: f2fs_down_read(&sbi->node_write)//block
- f2fs_flush_nat_entries
: {struct nat_entry}->flag |= BIT(IS_CHECKPOINTED)
- unblock_operations
: f2fs_up_write(&sbi->node_write)
f2fs_write_checkpoint//return
: f2fs_do_write_node_page()
f2fs_ioc_commit_atomic_write//return
SPO
Thread A calls f2fs_need_dentry_mark(sbi, ino), and the last_folio has
already been written once. However, the {struct nat_entry}->flag did not
have the IS_CHECKPOINTED set, causing set_dentry_mark(last_folio, 1) and
write last_folio again after Thread B finishes f2fs_write_checkpoint.
After SPO and reboot, it was detected that {struct node_info}->blk_addr
was not NULL_ADDR because Thread B successfully write the checkpoint.
This issue only occurs in atomic write scenarios. For regular file
fsync operations, the folio must be dirty. If
block_operations->f2fs_sync_node_pages successfully submit the folio
write, this path will not be executed. Otherwise, the
f2fs_write_checkpoint will need to wait for the folio write submission
to complete, as sbi->nr_pages[F2FS_DIRTY_NODES] > 0. Therefore, the
situation where f2fs_need_dentry_mark checks that the {struct
nat_entry}->flag /wo the IS_CHECKPOINTED flag, but the folio write has
already been submitted, will not occur.
Therefore, for atomic file fsync, sbi->node_write should be acquired
through __write_node_folio to ensure that the IS_CHECKPOINTED flag
correctly indicates that the checkpoint write has been completed. |
| In the Linux kernel, the following vulnerability has been resolved:
fbdev: rivafb: fix divide error in nv3_arb()
A userspace program can trigger the RIVA NV3 arbitration code by calling
the FBIOPUT_VSCREENINFO ioctl on /dev/fb*. When doing so, the driver
recomputes FIFO arbitration parameters in nv3_arb(), using state->mclk_khz
(derived from the PRAMDAC MCLK PLL) as a divisor without validating it
first.
In a normal setup, state->mclk_khz is provided by the real hardware and is
non-zero. However, an attacker can construct a malicious or misconfigured
device (e.g. a crafted/emulated PCI device) that exposes a bogus PLL
configuration, causing state->mclk_khz to become zero. Once
nv3_get_param() calls nv3_arb(), the division by state->mclk_khz in the gns
calculation causes a divide error and crashes the kernel.
Fix this by checking whether state->mclk_khz is zero and bailing out before
doing the division.
The following log reveals it:
rivafb: setting virtual Y resolution to 2184
divide error: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 PID: 2187 Comm: syz-executor.0 Not tainted 5.18.0-rc1+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
RIP: 0010:nv3_arb drivers/video/fbdev/riva/riva_hw.c:439 [inline]
RIP: 0010:nv3_get_param+0x3ab/0x13b0 drivers/video/fbdev/riva/riva_hw.c:546
Call Trace:
nv3CalcArbitration.constprop.0+0x255/0x460 drivers/video/fbdev/riva/riva_hw.c:603
nv3UpdateArbitrationSettings drivers/video/fbdev/riva/riva_hw.c:637 [inline]
CalcStateExt+0x447/0x1b90 drivers/video/fbdev/riva/riva_hw.c:1246
riva_load_video_mode+0x8a9/0xea0 drivers/video/fbdev/riva/fbdev.c:779
rivafb_set_par+0xc0/0x5f0 drivers/video/fbdev/riva/fbdev.c:1196
fb_set_var+0x604/0xeb0 drivers/video/fbdev/core/fbmem.c:1033
do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1109
fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1188
__x64_sys_ioctl+0x122/0x190 fs/ioctl.c:856 |
