net/rds: zero per-item info buffer before handing it to visitors
Summary
| CVE | CVE-2026-52995 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-06-24 17:17:10 UTC |
| Updated | 2026-07-15 13:06:47 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: net/rds: zero per-item info buffer before handing it to visitors rds_for_each_conn_info() and rds_walk_conn_path_info() both hand a caller-allocated on-stack u64 buffer to a per-connection visitor and then copy the full item_len bytes back to user space via rds_info_copy() regardless of how much of the buffer the visitor actually wrote. rds_ib_conn_info_visitor() and rds6_ib_conn_info_visitor() only write a subset of their output struct when the underlying rds_connection is not in state RDS_CONN_UP (src/dst addr, tos, sl and the two GIDs via explicit memsets). Several u32 fields (max_send_wr, max_recv_wr, max_send_sge, rdma_mr_max, rdma_mr_size, cache_allocs) and the 2-byte alignment hole between sl and cache_allocs remain as whatever stack contents preceded the visitor call and are then memcpy_to_user()'d out to user space. struct rds_info_rdma_connection and struct rds6_info_rdma_connection are the only rds_info_* structs in include/uapi/linux/rds.h that are not marked __attribute__((packed)), so they have a real alignment hole. The other info visitors (rds_conn_info_visitor, rds6_conn_info_visitor, rds_tcp_tc_info, ...) write all fields of their packed output struct today and are not known to be vulnerable, but a future visitor that adds a conditional write-path would have the same bug. Reproduction on a kernel built without CONFIG_INIT_STACK_ALL_ZERO=y: a local unprivileged user opens AF_RDS, sets SO_RDS_TRANSPORT=IB, binds to a local address on an RDMA-capable netdev (rxe soft-RoCE on any netdev is sufficient), sendto()'s any peer on the same subnet (fails cleanly but installs an rds_connection in the global hash in RDS_CONN_CONNECTING), then calls getsockopt(SOL_RDS, RDS_INFO_IB_CONNECTIONS). The returned 68-byte item contains 26 bytes of stack garbage including kernel text/data pointers: 0..7 0a 63 00 01 0a 63 00 02 src=10.99.0.1 dst=10.99.0.2 8..39 00 ... gids (memset-zeroed) 40..47 e0 92 a3 81 ff ff ff ff kernel pointer (max_send_wr) 48..55 7f 37 b5 81 ff ff ff ff kernel pointer (rdma_mr_max) 56..59 01 00 08 00 rdma_mr_size (garbage) 60..61 00 00 tos, sl 62..63 00 00 alignment padding 64..67 18 00 00 00 cache_allocs (garbage) Fix by zeroing the per-item buffer in both rds_for_each_conn_info() and rds_walk_conn_path_info() before invoking the visitor. This covers the IPv4/IPv6 IB visitors and hardens all current and future visitors against the same class of bug. No functional change for visitors that fully populate their output. Changes in v2: - retarget at the net tree (subject prefix "[PATCH net v2]", net/rds: prefix in the title) - pick up Reviewed-by tags from Sharath Srinivasan and Allison Henderson |
Risk And Classification
Primary CVSS: v3.1 5.5 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.001760000 probability, percentile 0.073310000 (date 2026-07-13)
Problem Types: NVD-CWE-noinfo
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Linux | Linux Kernel | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected ec16227e14141e4fd7ae76354c09dadfe2449d9e 81651e9d7dea1c048d2952f57632a042931d7b43 git | Not specified |
| CNA | Linux | Linux | affected ec16227e14141e4fd7ae76354c09dadfe2449d9e 0797b2e6901827694aa9c34c4c72118c8c97fba1 git | Not specified |
| CNA | Linux | Linux | affected ec16227e14141e4fd7ae76354c09dadfe2449d9e 5e67cc262afb384e835c3327e9d954eeaedc6a87 git | Not specified |
| CNA | Linux | Linux | affected ec16227e14141e4fd7ae76354c09dadfe2449d9e b6ba93a7b71ed443c9843eb12d27ed86f1e52694 git | Not specified |
| CNA | Linux | Linux | affected ec16227e14141e4fd7ae76354c09dadfe2449d9e c7cb9eed8215a790f052f49cdccf577720d2bb62 git | Not specified |
| CNA | Linux | Linux | affected ec16227e14141e4fd7ae76354c09dadfe2449d9e 91ce1bb6e4194dc2321748f68145359dcf86e350 git | Not specified |
| CNA | Linux | Linux | affected ec16227e14141e4fd7ae76354c09dadfe2449d9e 912ba2e5704fdb8bc5decda96dfc1a57838f0099 git | Not specified |
| CNA | Linux | Linux | affected ec16227e14141e4fd7ae76354c09dadfe2449d9e c88eb7e8d8397a8c1db59c425332c5a30b2a1682 git | Not specified |
| CNA | Linux | Linux | affected 2.6.30 | Not specified |
| CNA | Linux | Linux | unaffected 2.6.30 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.258 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.209 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.175 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.141 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.91 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.33 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0.10 7.0.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/c88eb7e8d8397a8c1db59c425332c5a30b2a1682 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/b6ba93a7b71ed443c9843eb12d27ed86f1e52694 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/0797b2e6901827694aa9c34c4c72118c8c97fba1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/91ce1bb6e4194dc2321748f68145359dcf86e350 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/912ba2e5704fdb8bc5decda96dfc1a57838f0099 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/c7cb9eed8215a790f052f49cdccf577720d2bb62 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/81651e9d7dea1c048d2952f57632a042931d7b43 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/5e67cc262afb384e835c3327e9d954eeaedc6a87 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.