CVE-2026-92500— ext4: use fsdata to track inline data write state and fix race
Quick assessment
Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
在 Linux 内核中，已解决以下漏洞： ext4：使用 fsdata 跟踪内联数据写入状态并修复竞态条件 在 处理函数中，不再检查实时 inode 状态（即 和 ），而是通过地址空间操作的 参数，显式传递 阶段所准备的写入状态。 问题背景： 在 和 之间，并发线程（例如 ）可能会将内联数据转换为 extent。如果这种情况发生， 处理函数会错过内联数据写入路径，并落入基于 extent 的写入逻辑。然而，由于在 阶段从未分配块缓冲区（block buffers），这会导致 为 NULL，从而引发空指针解引用或数据
Possible ATT&CK Techniques 1 AI
T1015Affected Version Matrix 8
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| Linux | Linux | 3fdcfb668fd78ec92d9bc2daddf1d41e2a8a30bb< bd8d74bd46d09905164255b8635fa58b45f41068 |
affected |
3fdcfb668fd78ec92d9bc2daddf1d41e2a8a30bb< 439aedfd7ae868d1d7b4930afe66091cb979cd5c |
affected | ||
3fdcfb668fd78ec92d9bc2daddf1d41e2a8a30bb< 7edbb323bab2b2a609016014caafdb651c898249 |
affected | ||
3.8 |
affected | ||
< 3.8 |
unaffected | ||
6.18.52≤ 6.18.* |
unaffected | ||
7.2.6≤ 7.2.* |
unaffected | ||
7.3-rc1≤ * |
unaffected |
Get alerts for future matching vulnerabilities
Log in to subscribe
I. Basic Information for CVE-2026-92500
Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗
Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.
Vulnerability Title
ext4: use fsdata to track inline data write state and fix race
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved:
ext4: use fsdata to track inline data write state and fix race
Instead of checking the live inode state (ext4_has_inline_data(inode)
and ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) in the
write_end handlers, use the fsdata parameter of the address space
operations to explicitly pass down the state in which write_begin
prepared the write.
A concurrent thread (such as ext4_page_mkwrite()) can convert the
inline data to an extent between write_begin and write_end. If this
happens, the write_end handlers would previously miss the inline
write_end path and fall through to extent-based write_end logic.
However, since block buffers were never allocated in write_begin,
this resulted in NULL pointer dereferences or data loss because
folio_buffers(folio) was NULL.
Define EXT4_WRITE_DATA_INLINE (4) as a bit flag (Bit 2), treating
fsdata as bitwise flags rather than mutually exclusive enums to keep
states of the write path independent. Communicate this state via
fsdata:
1) ext4_write_begin() and ext4_da_write_begin() set the
EXT4_WRITE_DATA_INLINE bit in *fsdata via bitwise OR when an inline
write is successfully prepared.
2) On entry, ext4_write_begin() clears the EXT4_WRITE_DATA_INLINE bit
to safely handle VFS retries (where generic_perform_write() bypasses
the fsdata initialization on its retry jump).
3) The write_end handlers perform a bitwise AND to check if the
EXT4_WRITE_DATA_INLINE bit is set and invoke the inline write_end
helper accordingly.
Furthermore, during a buffered write, ext4_write_inline_data_end()
acquires the xattr lock after preparing the write. If a concurrent
page fault (ext4_page_mkwrite()) converts the inline data to an extent
after the write_end handlers check the state but before
ext4_write_inline_data_end() acquires the xattr write lock, the
subsequent check will trigger a kernel panic via
BUG_ON(!ext4_has_inline_data(inode)).
To keep git history working and bisectability clean, replace the
BUG_ON check in ext4_write_inline_data_end() with a graceful error-
handling retry path in this same commit. If the inline data is cleared
after locking the xattr, we safely release all resources (releasing
iloc.bh, unlocking/putting the folio, stopping the active journal
transaction handle) and return 0 (VFS retry) to let the generic write
path retry the operation safely.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Affected Products
II. Public POCs for CVE-2026-92500
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POC
Premium
No public POC found.
Login to generate AI POCIII. Intelligence Information for CVE-2026-92500
请登录查看更多情报信息。
Patches & Fixes for CVE-2026-92500 (3)
Same Patch Batch · Linux · 2026-09-17 · 600 CVEs total
| CVE-2026-92489 | 9.8 CRITICAL | xfrm: Fix skb double-free in xfrm_dev_direct_output() |
| CVE-2026-90235 | 9.8 CRITICAL | sunrpc: xprtsock: annotate shared socket callbacks with READ_ONCE/WRITE_ONCE |
| CVE-2026-90173 | 9.8 CRITICAL | smb: smbdirect: free completion queues with ib_free_cq() |
| CVE-2026-90104 | 9.8 CRITICAL | NFSv4.1: zero referring call lists before decoding |
| CVE-2026-90151 | 9.8 CRITICAL | NFSv4: remove callback IDR entry on client allocation failure |
| CVE-2026-90110 | 9.4 CRITICAL | inetpeer: randomize RB-tree node comparison using SipHash |
| CVE-2026-90230 | 9.1 CRITICAL | nvmet: fix heap out-of-bounds read in nvmet_auth_negotiate() |
| CVE-2026-90414 | 9.1 CRITICAL | IB/isert: reject PDUs declaring more data than was received |
| CVE-2026-90413 | 9.1 CRITICAL | IB/isert: reject login PDUs declaring more data than was received |
| CVE-2026-90367 | 8.8 HIGH | wifi: mt76: mt7996: hold dev->mt76.mutex while disabling tx worker in SER |
| CVE-2026-90329 | 8.8 HIGH | HID: synchronize input before cleaning up a failed probe |
| CVE-2026-93189 | 8.8 HIGH | HID: core: quiesce input in hid_hw_stop() to prevent use-after-free |
| CVE-2026-90240 | 8.8 HIGH | iommu/vt-d: Flush context cache with correct SID when tearing down aliases |
| CVE-2026-90357 | 8.8 HIGH | wifi: mt76: mt7915: unlink TWT flow if the MCU rejects the agreement |
| CVE-2026-90286 | 8.8 HIGH | drm/amdgpu/gfx6: Use PFP on the compute queues too |
| CVE-2026-93042 | 8.8 HIGH | dmaengine: dw-edma: Terminate all descriptors without callbacks |
| CVE-2026-90256 | 8.8 HIGH | Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind |
| CVE-2026-90380 | 8.8 HIGH | wifi: mt76: mt792x: fix use-after-free in mt76_rx_poll_complete |
| CVE-2026-90381 | 8.8 HIGH | wifi: mt76: fix handling channel context with different bands in mt76_switch_vif_chanctx() |
| CVE-2026-90425 | 8.8 HIGH | iommu/tegra241-cmdqv: Require exactly one Stream ID for a vSID |
Showing top 20 of 600 CVEs. View all on vendor page → →
IV. Related Vulnerabilities
Same product: Linux
-
CVE-2026-98384
bpf: Fix out-of-bounds read of sk_protocol in bpf_sock_destr -
CVE-2026-98383
bpf: Disallow bpf_skb_pull_data() for LWT_SEG6LOCAL -
CVE-2026-98382
bpf: Reject dev-bound-only programs on other devices -
CVE-2026-98381
veth: manage XDP program pointers during channel resize -
CVE-2026-98380
net/sched: reject IDR error pointers when deleting actions
Same vendor: Linux
-
CVE-2026-98384
bpf: Fix out-of-bounds read of sk_protocol in bpf_sock_destr -
CVE-2026-98383
bpf: Disallow bpf_skb_pull_data() for LWT_SEG6LOCAL -
CVE-2026-98382
bpf: Reject dev-bound-only programs on other devices -
CVE-2026-98381
veth: manage XDP program pointers during channel resize -
CVE-2026-98380
net/sched: reject IDR error pointers when deleting actions
V. Comments for CVE-2026-92500
No comments yet