In the Linux kernel, the following vulnerability has been resolved:
nfsd: validate sockaddr length per family in listener_set
nfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY
attribute with no minimum length. A CAP_NET_ADMIN caller can send a
16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte
OOB read across three consumers (rpc_cmp_addr_port, svc_find_listener,
kernel_bind).
nfsd_nl_listener_set_doit() also parsed and validated each listener
entry inline in two separate loops, interleaved with mutating the
running listener configuration. The validation was duplicated, used an
open-coded "nla_len < sizeof(struct sockaddr)" check that was too short
for AF_INET6, and handled a malformed entry inconsistently depending on
which loop noticed it.
Add an nfsd_nl_validate_listeners() helper that walks the entire list
once and confirms each entry parses, carries both an address and a
transport name, and is long enough for its address family
(sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6)
for AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking
nfsd_mutex or creating the serv, so a malformed request fails cleanly
with no side effects.
Since every entry is known valid by the time the two existing loops
run, drop the redundant presence and per-family length checks from
both, leaving only the nla_parse_nested() call needed to extract the
data.
nfsd: validate sockaddr length per family in listener_set
nfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY
attribute with no minimum length. A CAP_NET_ADMIN caller can send a
16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte
OOB read across three consumers (rpc_cmp_addr_port, svc_find_listener,
kernel_bind).
nfsd_nl_listener_set_doit() also parsed and validated each listener
entry inline in two separate loops, interleaved with mutating the
running listener configuration. The validation was duplicated, used an
open-coded "nla_len < sizeof(struct sockaddr)" check that was too short
for AF_INET6, and handled a malformed entry inconsistently depending on
which loop noticed it.
Add an nfsd_nl_validate_listeners() helper that walks the entire list
once and confirms each entry parses, carries both an address and a
transport name, and is long enough for its address family
(sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6)
for AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking
nfsd_mutex or creating the serv, so a malformed request fails cleanly
with no side effects.
Since every entry is known valid by the time the two existing loops
run, drop the redundant presence and per-family length checks from
both, leaving only the nla_parse_nested() call needed to extract the
data.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Sat, 12 Sep 2026 08:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-119 |
Fri, 11 Sep 2026 23:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: nfsd: validate sockaddr length per family in listener_set nfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY attribute with no minimum length. A CAP_NET_ADMIN caller can send a 16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte OOB read across three consumers (rpc_cmp_addr_port, svc_find_listener, kernel_bind). nfsd_nl_listener_set_doit() also parsed and validated each listener entry inline in two separate loops, interleaved with mutating the running listener configuration. The validation was duplicated, used an open-coded "nla_len < sizeof(struct sockaddr)" check that was too short for AF_INET6, and handled a malformed entry inconsistently depending on which loop noticed it. Add an nfsd_nl_validate_listeners() helper that walks the entire list once and confirms each entry parses, carries both an address and a transport name, and is long enough for its address family (sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6) for AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking nfsd_mutex or creating the serv, so a malformed request fails cleanly with no side effects. Since every entry is known valid by the time the two existing loops run, drop the redundant presence and per-family length checks from both, leaving only the nla_parse_nested() call needed to extract the data. | |
| Title | nfsd: validate sockaddr length per family in listener_set | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-11T19:46:18.076Z
Reserved: 2026-09-11T19:38:34.750Z
Link: CVE-2026-89700
No data.
Status : Received
Published: 2026-09-11T20:19:57.187
Modified: 2026-09-11T20:19:57.187
Link: CVE-2026-89700
No data.
OpenCVE Enrichment
Updated: 2026-09-12T08:15:07Z
Weaknesses