CVE-2026-80787
nvmet: pci-epf: fix use-after-free in nvmet_pci_epf_exec_iod_work()
Description
In the Linux kernel, the following vulnerability has been resolved: nvmet: pci-epf: fix use-after-free in nvmet_pci_epf_exec_iod_work() nvmet_pci_epf_exec_iod_work() submits an I/O command with req->execute() and then waits for the command to complete and transfers the data back to the host. This wait is not needed for commands that do not transfer data from the device to the host. To decide whether that wait is needed, it reads iod->data_len and iod->dma_dir after calling req->execute(). However, once req->execute() is called, the command may complete asynchronously on another CPU. For commands that do not require a device-to-host data transfer, nvmet_pci_epf_queue_response() calls nvmet_pci_epf_complete_iod() directly, which can free the iod before it reads iod->data_len and iod->dma_dir, resulting in the KFENCE use-after- free: BUG: KFENCE: use-after-free read in nvmet_pci_epf_exec_iod_work+0x288/0x798 [nvmet_pci_epf] Use-after-free read at 0x00000000fdfa6d03 (in kfence-#63): nvmet_pci_epf_exec_iod_work+0x288/0x798 [nvmet_pci_epf] process_one_work+0x15c/0x4f0 worker_thread+0x18c/0x30c kthread+0x130/0x140 ret_from_fork+0x10/0x20 kfence-#63: 0x00000000e3de0e71-0x00000000c938ad62, size=712, cache=kmalloc-1k allocated by task 10 on cpu 0 at 73.995480s (0.005122s ago): mempool_kmalloc+0x1c/0x28 mempool_alloc_noprof+0x40/0x9c nvmet_pci_epf_poll_sqs_work+0xd4/0x344 [nvmet_pci_epf] process_one_work+0x15c/0x4f0 worker_thread+0x18c/0x30c kthread+0x130/0x140 ret_from_fork+0x10/0x20 freed by task 131 on cpu 3 at 73.995521s (0.008385s ago): mempool_kfree+0x10/0x20 mempool_free+0x44/0x64 nvmet_pci_epf_free_iod+0x88/0x98 [nvmet_pci_epf] nvmet_pci_epf_cq_work+0xfc/0x280 [nvmet_pci_epf] process_one_work+0x15c/0x4f0 worker_thread+0x18c/0x30c kthread+0x130/0x140 ret_from_fork+0x10/0x20 Fix this by referring to iod->data_len and iod->dma_dir before calling req->execute(). The remaining iod accesses such as iod->status are only reached on the device-to-host read path. In this case, nvmet_pci_epf_queue_response() signals iod->done instead of freeing the iod, so the iod stays valid.
INFO
Published Date :
Sept. 4, 2026, 4:18 p.m.
Last Modified :
Sept. 4, 2026, 4:18 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Check iod->data_len and iod->dma_dir before req->execute().
- Ensure iod remains valid for device-to-host reads.
- Apply the patch to the Linux kernel.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-80787.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-80787 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-80787
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-80787 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-80787 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 04, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: nvmet: pci-epf: fix use-after-free in nvmet_pci_epf_exec_iod_work() nvmet_pci_epf_exec_iod_work() submits an I/O command with req->execute() and then waits for the command to complete and transfers the data back to the host. This wait is not needed for commands that do not transfer data from the device to the host. To decide whether that wait is needed, it reads iod->data_len and iod->dma_dir after calling req->execute(). However, once req->execute() is called, the command may complete asynchronously on another CPU. For commands that do not require a device-to-host data transfer, nvmet_pci_epf_queue_response() calls nvmet_pci_epf_complete_iod() directly, which can free the iod before it reads iod->data_len and iod->dma_dir, resulting in the KFENCE use-after- free: BUG: KFENCE: use-after-free read in nvmet_pci_epf_exec_iod_work+0x288/0x798 [nvmet_pci_epf] Use-after-free read at 0x00000000fdfa6d03 (in kfence-#63): nvmet_pci_epf_exec_iod_work+0x288/0x798 [nvmet_pci_epf] process_one_work+0x15c/0x4f0 worker_thread+0x18c/0x30c kthread+0x130/0x140 ret_from_fork+0x10/0x20 kfence-#63: 0x00000000e3de0e71-0x00000000c938ad62, size=712, cache=kmalloc-1k allocated by task 10 on cpu 0 at 73.995480s (0.005122s ago): mempool_kmalloc+0x1c/0x28 mempool_alloc_noprof+0x40/0x9c nvmet_pci_epf_poll_sqs_work+0xd4/0x344 [nvmet_pci_epf] process_one_work+0x15c/0x4f0 worker_thread+0x18c/0x30c kthread+0x130/0x140 ret_from_fork+0x10/0x20 freed by task 131 on cpu 3 at 73.995521s (0.008385s ago): mempool_kfree+0x10/0x20 mempool_free+0x44/0x64 nvmet_pci_epf_free_iod+0x88/0x98 [nvmet_pci_epf] nvmet_pci_epf_cq_work+0xfc/0x280 [nvmet_pci_epf] process_one_work+0x15c/0x4f0 worker_thread+0x18c/0x30c kthread+0x130/0x140 ret_from_fork+0x10/0x20 Fix this by referring to iod->data_len and iod->dma_dir before calling req->execute(). The remaining iod accesses such as iod->status are only reached on the device-to-host read path. In this case, nvmet_pci_epf_queue_response() signals iod->done instead of freeing the iod, so the iod stays valid. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/80xxx/CVE-2026-80787.json">CVE-2026-80787</a> Added Reference https://git.kernel.org/stable/c/1ed1eeaef55cebf2d74b3ef104c20bdab719b165 Added Reference https://git.kernel.org/stable/c/20be486d1c225402b067391e72ff5b0dd8ebff76 Added Reference https://git.kernel.org/stable/c/c9e9bb757971485b4e8414b1744507af186d72c9 Added Reference https://git.kernel.org/stable/c/cede8d2852570c79b9bbb9527255ae9ed3317b82