CVE-2024-36489
In the Linux kernel, the following vulnerability has been resolved:
tls: fix missing memory barrier in tls_init
In tls_init(), a write memory barrier is missing, and store-store
reordering may cause NULL dereference in tls_{setsockopt,getsockopt}.
CPU0 CPU1
// In tls_init()
// In tls_ctx_create()
ctx = kzalloc()
ctx->sk_proto = READ_ONCE(sk->sk_prot) -(1)
// In update_sk_prot()
WRITE_ONCE(sk->sk_prot, tls_prots) -(2)
// In sock_common_setsockopt()
READ_ONCE(sk->sk_prot)->setsockopt()
// In tls_{setsockopt,getsockopt}()
ctx->sk_proto->setsockopt() -(3)
In the above scenario, when (1) and (2) are reordered, (3) can observe
the NULL value of ctx->sk_proto, causing NULL dereference.
To fix it, we rely on rcu_assign_pointer() which implies the release
barrier semantic. By moving rcu_assign_pointer() after ctx->sk_proto is
initialized, we can ensure that ctx->sk_proto are visible when
changing sk->sk_prot.
Weaknesses
- CWE-476
- NULL Pointer Dereference
- CVE Status
- PUBLISHED
- NVD Status
- Analyzed
- CNA
- kernel.org
- Published Date
-
2024-06-21 11:15:10
(2 months ago) - Updated Date
-
2024-09-09 13:32:13
(7 days ago)
Affected Products
Configuration #1
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