net: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove
In the Linux kernel, the following vulnerability has been resolved: net: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove In qrtr_port_remove(), the socket reference count is decremented via __sock_put() before the port is removed from the qrtr_ports XArray and before the RCU grace period elapses. This breaks the fundamental RCU update paradigm. It exposes a race window where a concurrent RCU reader (such as qrtr_reset_ports() or qrtr_port_lookup()) can obtain a pointer to the socket from the XArray, and attempt to call sock_hold() on a socket whose reference count has already dropped to zero. This exact race condition was hit during syzkaller fuzzing, leading to the following refcount saturation warning and a potential Use-After-Free: refcount_t: saturated; leaking memory. WARNING: CPU: 3 PID: 1273 at lib/refcount.c:22 refcount_warn_saturate+0xae/0x1d0 Modules linked in: qrtr(+) bochs drm_shmem_helper ... Call Trace: qrtr_reset_ports net/qrtr/af_qrtr.c:768 [inline] [qrtr] __qrtr_bind.isra.0+0x48b/0x570 net/qrtr/af_qrtr.c:805 [qrtr] qrtr_bind+0x17d/0x210 net/qrtr/af_qrtr.c:901 [qrtr] kernel_bind+0xe4/0x120 net/socket.c:3592 qrtr_ns_init+0x1a6/0x380 net/qrtr/ns.c:715 [qrtr] qrtr_proto_init+0x3b/0xff0 net/qrtr/af_qrtr.c:169 [qrtr] do_one_initcall+0xf5/0x5e0 init/main.c:1283 ... Fix this by deferring the reference count decrement until after the xa_erase() and the synchronize_rcu() complete. (Note: The v1 of this patch incorrectly replaced __sock_put() with so
CVE-2026-52947
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-2026-52947
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": "bdabad3e363d825ddf9679dd431cca0b2c30f881",
"lessThan": "2aa4c12723fe432e623462a3be42a197a128722b",
"versionType": "git"
},
{
"status": "affected",
"version": "bdabad3e363d825ddf9679dd431cca0b2c30f881",
"lessThan": "03bfa95e452e2b6ccd76a332060ae4feaf5ad84d",
"versionType": "git"
},
{
"status": "affected",
"version": "bdabad3e363d825ddf9679dd431cca0b2c30f881",
"lessThan": "474293d90880622fde9d2430fb0165767090f7b3",
"versionType": "git"
},
{
"status": "affected",
"version": "bdabad3e363d825ddf9679dd431cca0b2c30f881",
"lessThan": "2047c2aa0963bb2872fd722300a15bcb441a4c00",
"versionType": "git"
},
{
"status": "affected",
"version": "bdabad3e363d825ddf9679dd431cca0b2c30f881",
"lessThan": "7de2d447072be3b1a76793f034432338fc9c494b",
"versionType": "git"
},
{
"status": "affected",
"version": "bdabad3e363d825ddf9679dd431cca0b2c30f881",
"lessThan": "ab269990ed58143a92a263be1bee626d82ac03da",
"versionType": "git"
},
{
"status": "affected",
"version": "bdabad3e363d825ddf9679dd431cca0b2c30f881",
"lessThan": "3b20ec8f31e8a6a6782243f473b0abd3463621df",
"versionType": "git"
},
{
"status": "affected",
"version": "bdabad3e363d825ddf9679dd431cca0b2c30f881",
"lessThan": "a2171131ecda1ed61a594a1eb715e75fdad0fef5",
"versionType": "git"
}
],
"programFiles": [
"net/qrtr/af_qrtr.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.7"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.7",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.259",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.210",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.176",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.143",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.94",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.36",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.13",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/qrtr/af_qrtr.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-52947
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #40707 · Revision 1
- Added to Heist Feed
- Publisher date