rds: ib: Clear the sg list when mapping an MR fails
rds_ib_map_frmr() stores the caller's scatterlist in the MR before DMA
mapping and registration can fail. On failure, __rds_rdma_map() unpins
the pages and frees the scatterlist, but rds_ib_free_frmr() can still
return the MR to the pool with the stale pointer set.
This leaves the pool with a dangling scatterlist and can lead to local
privilege escalation. KASAN detects the resulting use-after-free when the
MR is later torn down:
BUG: KASAN: slab-use-after-free in __rds_ib_teardown_mr
Read of size 8
Call Trace:
__rds_ib_teardown_mr
rds_ib_unreg_frmr
rds_ib_flush_mr_pool
rds_ib_flush_mrs
rds_free_mr
rds_setsockopt
Store the scatterlist in the MR only after DMA mapping succeeds. If DMA
mapping fails, return directly while the MR fields remain clear; the caller
keeps ownership of the scatterlist and its pinned pages. If a later
registration step fails, unmap the scatterlist and clear the MR fields
before returning.
Metrics
Affected Vendors & Products
No data.
No data.
OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.
No data.
No advisories yet.
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Mon, 19 Oct 2026 00:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-416 |
Sun, 18 Oct 2026 15:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: rds: ib: Clear the sg list when mapping an MR fails rds_ib_map_frmr() stores the caller's scatterlist in the MR before DMA mapping and registration can fail. On failure, __rds_rdma_map() unpins the pages and frees the scatterlist, but rds_ib_free_frmr() can still return the MR to the pool with the stale pointer set. This leaves the pool with a dangling scatterlist and can lead to local privilege escalation. KASAN detects the resulting use-after-free when the MR is later torn down: BUG: KASAN: slab-use-after-free in __rds_ib_teardown_mr Read of size 8 Call Trace: __rds_ib_teardown_mr rds_ib_unreg_frmr rds_ib_flush_mr_pool rds_ib_flush_mrs rds_free_mr rds_setsockopt Store the scatterlist in the MR only after DMA mapping succeeds. If DMA mapping fails, return directly while the MR fields remain clear; the caller keeps ownership of the scatterlist and its pinned pages. If a later registration step fails, unmap the scatterlist and clear the MR fields before returning. | |
| Title | rds: ib: Clear the sg list when mapping an MR fails | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Projects
Sign in to view the affected projects.
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-18T15:17:41.420Z
Reserved: 2026-09-25T10:25:14.355Z
Link: CVE-2026-98524
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-10-18T16:17:03.827
Modified: 2026-10-18T16:17:03.827
Link: CVE-2026-98524
Redhat
No data.
OpenCVE Enrichment
Updated: 2026-10-18T23:45:07Z