Bluetooth: L2CAP: fix race l2cap_sock_cleanup_listen() vs. put_chan
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: fix race l2cap_sock_cleanup_listen() vs. put_chan For L2CAP sockets without owning sk->sk_socket, reading l2cap_pi(sk)->chan may race against concurrent l2cap_sock_kill() -> l2cap_sock_put_chan(). This excludes simultaneous proto_ops callbacks, but access in l2cap_sock_cleanup_listen() has unsafe lockless read. [Task 1] [Task 2 (hdev->workqueue)] l2cap_sock_release(parent) l2cap_disconn_cfm l2cap_sock_cleanup_listen l2cap_conn_del bt_accept_dequeue l2cap_chan_del lock_sock(sk) l2cap_sock_teardown_cb bt_accept_unlink bt_sk(sk)->parent = NULL release_sock(sk) ----------------> lock_sock(sk) parent = /* NULL */ lock_sock(sk) <--------------------- release_sock(sk) sock_set_flag(sk, SOCK_ZAPPED) l2cap_sock_close_cb l2cap_sock_kill(sk) l2cap_sock_put_chan chan = READ l2cap_pi(sk)->chan l2cap_pi(sk)->chan = NULL l2cap_chan_hold_unless_zero l2cap_put_chan(chan) kref_get_unless_zero(&chan->ref) Task 1 may observe NULL which causes null-ptr-deref. Fix the race by taking lock_sock() in l2cap_sock_kill() to synchronize with l2cap_sock_cleanup_listen(). hold_unless_zero() is not needed here, l2cap_pi(sk)->chan owns reference if it is non-NULL. Clarify code comments vs. locking.
CVE-2026-90091
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-2026-90091
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": "b39298044e5534612511a2ff5de03ba5f6e7a820",
"lessThan": "827de6bd2865b22aaabd554540def3b8a33018ab",
"versionType": "git"
},
{
"status": "affected",
"version": "8c37e4338c801ebb8cee52436c01c41e009f6e87",
"lessThan": "7c7ac736b50fa259ed1bdddc18d79523f07c0442",
"versionType": "git"
},
{
"status": "affected",
"version": "84e718b6a814edc84159361f9f454a4e92ae91ae",
"lessThan": "4f8c63fe0097c9f6ea34409f82f79b3894903d91",
"versionType": "git"
},
{
"status": "affected",
"version": "36da806f7fbaee56ad9e81859deec203f9728700",
"lessThan": "61d5ddbd524c715b224cbe7e9f01da4e05098b19",
"versionType": "git"
},
{
"status": "affected",
"version": "6fef032af0092ed5ccb767239a9ac1bc38c08a40",
"lessThan": "32a7bc6e93be36b37fe61f351d312d358195bd61",
"versionType": "git"
},
{
"status": "affected",
"version": "6fef032af0092ed5ccb767239a9ac1bc38c08a40",
"lessThan": "66d6ef18548ae6d7dd452b84115fc82c0a73a4ea",
"versionType": "git"
},
{
"status": "affected",
"version": "733e76e74e406c1d1ddc7369420dd8a47f48bb8a",
"versionType": "git"
},
{
"status": "affected",
"version": "6.1.178",
"lessThan": "6.1.188",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.6.145",
"lessThan": "6.6.157",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.12.97",
"lessThan": "6.12.110",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.18.40",
"lessThan": "6.18.52",
"versionType": "semver"
},
{
"status": "affected",
"version": "7.1.5",
"lessThan": "7.2",
"versionType": "semver"
}
],
"programFiles": [
"include/net/bluetooth/l2cap.h",
"net/bluetooth/l2cap_sock.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "7.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "7.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.1.188",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.110",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.52",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.6",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"include/net/bluetooth/l2cap.h",
"net/bluetooth/l2cap_sock.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-90091
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #36503 · Revision 1
- Added to Heist Feed
- Publisher date