net/9p: fix race condition on rdma->state in trans_rdma.c
In the Linux kernel, the following vulnerability has been resolved: net/9p: fix race condition on rdma->state in trans_rdma.c The rdma->state field is modified without holding req_lock in both recv_done() and p9_cm_event_handler(), while rdma_request() accesses the same field under the req_lock spinlock. This inconsistent locking creates a race condition: - recv_done() running in softirq completion context sets rdma->state = P9_RDMA_FLUSHING without acquiring req_lock - p9_cm_event_handler() modifies rdma->state at multiple points (ADDR_RESOLVED, ROUTE_RESOLVED, ESTABLISHED, CLOSED) without req_lock - rdma_request() uses spin_lock_irqsave(&rdma->req_lock, flags) to protect the read-modify-write of rdma->state The race can cause lost state transitions: recv_done() or the CM event handler could set state to FLUSHING/CLOSED while rdma_request() is concurrently checking or modifying state under the lock, leading to the FLUSHING transition being silently overwritten by CLOSING. This corrupts the connection state machine and can cause use-after-free on RDMA request objects during teardown. Fix by adding req_lock protection to all rdma->state modifications in recv_done() and p9_cm_event_handler(), matching the pattern already used in rdma_request(). Use spin_lock_irqsave/spin_unlock_irqrestore in the CM event handler since it can race with recv_done() which runs in softirq context. Tested with a kernel module that races two threads (simulating rdma_request and recv_done/CM handler)
CVE-2026-72491
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-72491
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "4cee2b8766045059d5e0b8114837b4a8efe827ac",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "5424138848eb7d7d8a7196676e90a2cbf2142454",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "3970a19a80de530b801b6256354d4a529a9a2d6c",
"versionType": "git"
},
{
"status": "affected",
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"lessThan": "8aadc136d8e8d8fc95d7982d213cfe2234dfcf2b",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "151f8cf5b23d8a534d884432a82a6d54d5a61989",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "13bf9879b778b2f4b260b45bed18f31806120d1e",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "ebbcbe5c0db215feecc17def06178da443f4eea6",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "7d54894a1ee265a72d70f7cae1da6cc774cccc71",
"versionType": "git"
},
{
"status": "affected",
"version": "3479b3c35e82ed10aa0ca2ee9e78c4eded06ba62",
"versionType": "git"
},
{
"status": "affected",
"version": "c01ddaa54d7411e964ffd250c018d8469c5852f2",
"versionType": "git"
},
{
"status": "affected",
"version": "9e69c673fe077b8dc491cd8406c9bdcb1f76dee2",
"versionType": "git"
},
{
"status": "affected",
"version": "e48e7e27e4dfd00c81e0381e7cee610cce021452",
"versionType": "git"
},
{
"status": "affected",
"version": "4.4.185",
"lessThan": "4.5",
"versionType": "semver"
},
{
"status": "affected",
"version": "4.9.185",
"lessThan": "4.10",
"versionType": "semver"
},
{
"status": "affected",
"version": "4.14.132",
"lessThan": "4.15",
"versionType": "semver"
},
{
"status": "affected",
"version": "4.19.57",
"lessThan": "4.20",
"versionType": "semver"
}
],
"programFiles": [
"net/9p/trans_rdma.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.20"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.20",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.261",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.212",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/9p/trans_rdma.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-72491
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #33066 · Revision 1
- Added to Heist Feed
- Publisher date