bpf, sockmap: Reject unhashed UDP sockets on sockmap update
In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Reject unhashed UDP sockets on sockmap update UDP sockets get SOCK_RCU_FREE set when (auto-)bound. This means sk_is_refcounted(unbound) = true, while sk_is_refcounted(bound) = false. Because sockmap accepts unbound UDP sockets, a BPF program can increment a socket's refcount via lookup. If the socket is subsequently bound, the transition from unbound to bound causes bpf_sk_release() to skip the decrement of the refcount, causing a memory leak. unreferenced object 0xffff88810bc2eb40 (size 1984): comm "test_progs", pid 2451, jiffies 4295320596 hex dump (first 32 bytes): 7f 00 00 01 7f 00 00 01 d2 04 1b b7 04 d2 00 00 ................ 02 00 01 40 00 00 00 00 00 00 00 00 00 00 00 00 ...@............ backtrace (crc bdee079d): kmem_cache_alloc_noprof+0x557/0x660 sk_prot_alloc+0x69/0x240 sk_alloc+0x30/0x460 inet_create+0x2ce/0xf80 __sock_create+0x25b/0x5c0 __sys_socket+0x119/0x1d0 __x64_sys_socket+0x72/0xd0 do_syscall_64+0xa1/0x5f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e Instead of special-casing for refcounted sockets, reject unhashed UDP sockets during sockmap updates, as there is no benefit to supporting those. This effectively reverts the commit under Fixes, with two exceptions: 1. sock_map_sk_state_allowed() maintains a fall-through `return true`. 2. In the spirit of commit b8b8315e39ff ("bpf, sockmap: Remove unhash handler for BPF sockmap usage"), the proto::unhash BPF handler is not reintroduce
CVE-2026-68386
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: osv:CVE-2026-68386
Kernel
Source reference: /affected/1/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 6.1.183
Source reference:
/affected/1/ranges6.6.148Source reference:
/affected/1/ranges6.12.101Source reference:
/affected/1/ranges6.18.42Source reference:
/affected/1/ranges7.1.6Source reference:
/affected/1/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "0c48eefae712c2fd91480346a07a1a9cd0f9470b"
},
{
"fixed": "2271276ac5279d2d204be7739a1a28d4ef6cf608"
},
{
"fixed": "7ffe529e7127411806c8692fb1490f552c629dc2"
},
{
"fixed": "17b7ef6b86112a4e61cee1e9009a4b318e3225c5"
},
{
"fixed": "250474c69bc3fc48a5fc21d7c349f279caad947a"
},
{
"fixed": "8692655da369961128658cf8539334b6a960ecb0"
},
{
"fixed": "66efd3368ae10d05e08fbe6425b50fdec7186ac7"
}
]
}
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68386.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "5.15.0"
},
{
"fixed": "6.1.183"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.2.0"
},
{
"fixed": "6.6.148"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.7.0"
},
{
"fixed": "6.12.101"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.13.0"
},
{
"fixed": "6.18.42"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.19.0"
},
{
"fixed": "7.1.6"
}
]
}
],
"package": {
"name": "Kernel",
"ecosystem": "Linux"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68386.json"
}
}
]- Related CVEs
- CVE-2026-68386
Source reference:
/id
Publisher severity
No explicit severity was provided.
- Event
- #50729 · Revision 1
- Added to Heist Feed
- Publisher date