packet: synchronize pressure clearing with ring reconfiguration
In the Linux kernel, the following vulnerability has been resolved: packet: synchronize pressure clearing with ring reconfiguration packet_set_ring() updates the RX ring state under sk_receive_queue.lock, but used to publish the tpacket receive mode through po->prot_hook.func after releasing that lock. packet_poll() and packet_recvmsg() can then run the pressure clearing path after the ring has been cleared while still seeing tpacket_rcv, causing __packet_rcv_has_room() to dereference stale or NULL ring storage. Move the existing receive hook assignment into the same sk_receive_queue.lock section as the ring state update. Keep the assignment otherwise unchanged, including on TX ring reconfiguration, to avoid adding behavior changes that are not required for the fix. Serialize packet_recvmsg() pressure clearing with the same queue lock only after PACKET_SOCK_PRESSURE has been observed. If the flag is clear and the socket has moved away from tpacket_rcv, packet_set_ring() has already detached the socket and waited for synchronize_net(), so no new packet input can set the flag again. packet_poll() already holds sk_receive_queue.lock, so it uses the new unlocked helper directly.
CVE-2026-74666
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-2026-74666
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": "2ccdbaa6d55b0656244ba57c4b56765a0af76c0a",
"lessThan": "bf3c8e86bc8ad111be3f3136125e255344bcb3da",
"versionType": "git"
},
{
"status": "affected",
"version": "2ccdbaa6d55b0656244ba57c4b56765a0af76c0a",
"lessThan": "8cfb2e71926a682f36c4240067d424074dd8f70f",
"versionType": "git"
},
{
"status": "affected",
"version": "2ccdbaa6d55b0656244ba57c4b56765a0af76c0a",
"lessThan": "f015c9de92b731814059a343b765c60c0196225c",
"versionType": "git"
},
{
"status": "affected",
"version": "2ccdbaa6d55b0656244ba57c4b56765a0af76c0a",
"lessThan": "cf8189b82bb93f219ab740e0346c919ad65ada62",
"versionType": "git"
},
{
"status": "affected",
"version": "2ccdbaa6d55b0656244ba57c4b56765a0af76c0a",
"lessThan": "ad740b4990347521f0db260d381f9f74e7b340ba",
"versionType": "git"
},
{
"status": "affected",
"version": "2ccdbaa6d55b0656244ba57c4b56765a0af76c0a",
"lessThan": "2c7b5eb87b2b288cdbde825f21d2b83b2f5da747",
"versionType": "git"
},
{
"status": "affected",
"version": "2ccdbaa6d55b0656244ba57c4b56765a0af76c0a",
"lessThan": "a08196c3cc105947746ec21309edfbb60275fcdb",
"versionType": "git"
},
{
"status": "affected",
"version": "2ccdbaa6d55b0656244ba57c4b56765a0af76c0a",
"lessThan": "1a35da325cac4d5bcad76a2aa943408a6f1d9000",
"versionType": "git"
}
],
"programFiles": [
"net/packet/af_packet.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.267",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.218",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.185",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.152",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.104",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.45",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.9",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/packet/af_packet.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74666
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #34264 · Revision 1
- Added to Heist Feed
- Publisher date