CVE-2025-37894: net: use sock_gen_put() when sk_state is TCP_TIME_WAIT

Vulnerability summary

CVE-2025-37894 is a critical (CVSS 9.8) NULL Pointer Dereference vulnerability in linux. EPSS estimates a 0.49% chance of exploitation in the next 30 days, higher than 41.9% of scored vulnerabilities.

Timeline

1. 20-05-2025
   PublishedVulnerability first disclosed.
2. 05-08-2026
   Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: net: use sock_gen_put() when sk_state is TCP_TIME_WAIT It is possible for a pointer of type struct inet_timewait_sock to be returned from the functions __inet_lookup_established() and __inet6_lookup_established(). This can cause a crash when the returned pointer is of type struct inet_timewait_sock and sock_put() is called on it. The following is a crash call stack that shows sk->sk_wmem_alloc being accessed in sk_free() during the call to sock_put() on a struct inet_timewait_sock pointer. To avoid this issue, use sock_gen_put() instead of sock_put() when sk->sk_state is TCP_TIME_WAIT. mrdump.ko ipanic() + 120 vmlinux notifier_call_chain(nr_to_call=-1, nr_calls=0) + 132 vmlinux atomic_notifier_call_chain(val=0) + 56 vmlinux panic() + 344 vmlinux add_taint() + 164 vmlinux end_report() + 136 vmlinux kasan_report(size=0) + 236 vmlinux report_tag_fault() + 16 vmlinux do_tag_recovery() + 16 vmlinux __do_kernel_fault() + 88 vmlinux do_bad_area() + 28 vmlinux do_tag_check_fault() + 60 vmlinux do_mem_abort() + 80 vmlinux el1_abort() + 56 vmlinux el1h_64_sync_handler() + 124 vmlinux > 0xFFFFFFC080011294() vmlinux __lse_atomic_fetch_add_release(v=0xF2FFFF82A896087C) vmlinux __lse_atomic_fetch_sub_release(v=0xF2FFFF82A896087C) vmlinux arch_atomic_fetch_sub_release(i=1, v=0xF2FFFF82A896087C) + 8 vmlinux raw_atomic_fetch_sub_release(i=1, v=0xF2FFFF82A896087C) + 8 vmlinux atomic_fetch_sub_release(i=1, v=0xF2FFFF82A896087C) + 8 vmlinux __refcount_sub_and_test(i=1, r=0xF2FFFF82A896087C, oldp=0) + 8 vmlinux __refcount_dec_and_test(r=0xF2FFFF82A896087C, oldp=0) + 8 vmlinux refcount_dec_and_test(r=0xF2FFFF82A896087C) + 8 vmlinux sk_free(sk=0xF2FFFF82A8960700) + 28 vmlinux sock_put() + 48 vmlinux tcp6_check_fraglist_gro() + 236 vmlinux tcp6_gro_receive() + 624 vmlinux ipv6_gro_receive() + 912 vmlinux dev_gro_receive() + 1116 vmlinux napi_gro_receive() + 196 ccmni.ko ccmni_rx_callback() + 208 ccmni.ko ccmni_queue_recv_skb() + 388 ccci_dpmaif.ko dpmaif_rxq_push_thread() + 1088 vmlinux kthread() + 268 vmlinux 0xFFFFFFC08001F30C()

• CWE-476NULL Pointer DereferenceThe product dereferences a pointer that it expects to be valid but is NULL.