CVE-2025-21683

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> bpf: Fix bpf_sk_select_reuseport() memory leak<br /> <br /> As pointed out in the original comment, lookup in sockmap can return a TCP<br /> ESTABLISHED socket. Such TCP socket may have had SO_ATTACH_REUSEPORT_EBPF<br /> set before it was ESTABLISHED. In other words, a non-NULL sk_reuseport_cb<br /> does not imply a non-refcounted socket.<br /> <br /> Drop sk&amp;#39;s reference in both error paths.<br /> <br /> unreferenced object 0xffff888101911800 (size 2048):<br /> comm "test_progs", pid 44109, jiffies 4297131437<br /> hex dump (first 32 bytes):<br /> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................<br /> 80 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 ................<br /> backtrace (crc 9336483b):<br /> __kmalloc_noprof+0x3bf/0x560<br /> __reuseport_alloc+0x1d/0x40<br /> reuseport_alloc+0xca/0x150<br /> reuseport_attach_prog+0x87/0x140<br /> sk_reuseport_attach_bpf+0xc8/0x100<br /> sk_setsockopt+0x1181/0x1990<br /> do_sock_setsockopt+0x12b/0x160<br /> __sys_setsockopt+0x7b/0xc0<br /> __x64_sys_setsockopt+0x1b/0x30<br /> do_syscall_64+0x93/0x180<br /> entry_SYSCALL_64_after_hwframe+0x76/0x7e