{"id":69502,"date":"2025-09-04T21:32:14","date_gmt":"2025-09-04T18:02:14","guid":{"rendered":"https:\/\/afaghhosting.net\/blog\/cve-2025-38727-netlink-avoid-infinite-retry-looping-in-netlink_unicast\/"},"modified":"2025-09-04T21:32:14","modified_gmt":"2025-09-04T18:02:14","slug":"cve-2025-38727-netlink-avoid-infinite-retry-looping-in-netlink_unicast","status":"publish","type":"post","link":"https:\/\/afaghhosting.net\/blog\/cve-2025-38727-netlink-avoid-infinite-retry-looping-in-netlink_unicast\/","title":{"rendered":"CVE-2025-38727 &#8211; netlink: avoid infinite retry looping in netlink_unicast()"},"content":{"rendered":"<p><strong>CVE ID : <\/strong>CVE-2025-38727<br \/>\n<br \/>\n<strong>Published : <\/strong> Sept. 4, 2025, 4:15 p.m. | 56\u00a0minutes ago<br \/>\n<br \/>\n<strong>Description : <\/strong>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>netlink: avoid infinite retry looping in netlink_unicast()<\/p>\n<p>netlink_attachskb() checks for the socket&#8217;s read memory allocation<br \/>\nconstraints. Firstly, it has:<\/p>\n<p>  rmem sk_rcvbuf)<\/p>\n<p>to check if the just increased rmem value fits into the socket&#8217;s receive<br \/>\nbuffer. If not, it proceeds and tries to wait for the memory under:<\/p>\n<p>  rmem + skb-&gt;truesize &gt; READ_ONCE(sk-&gt;sk_rcvbuf)<\/p>\n<p>The checks don&#8217;t cover the case when skb-&gt;truesize + sk-&gt;sk_rmem_alloc is<br \/>\nequal to sk-&gt;sk_rcvbuf. Thus the function neither successfully accepts<br \/>\nthese conditions, nor manages to reschedule the task &#8211; and is called in<br \/>\nretry loop for indefinite time which is caught as:<\/p>\n<p>  rcu: INFO: rcu_sched self-detected stall on CPU<br \/>\n  rcu:     0-&#8230;.: (25999 ticks this GP) idle=ef2\/1\/0x4000000000000000 softirq=262269\/262269 fqs=6212<br \/>\n  (t=26000 jiffies g=230833 q=259957)<br \/>\n  NMI backtrace for cpu 0<br \/>\n  CPU: 0 PID: 22 Comm: kauditd Not tainted 5.10.240 #68<br \/>\n  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc42 04\/01\/2014<br \/>\n  Call Trace:<\/p>\n<p>  dump_stack lib\/dump_stack.c:120<br \/>\n  nmi_cpu_backtrace.cold lib\/nmi_backtrace.c:105<br \/>\n  nmi_trigger_cpumask_backtrace lib\/nmi_backtrace.c:62<br \/>\n  rcu_dump_cpu_stacks kernel\/rcu\/tree_stall.h:335<br \/>\n  rcu_sched_clock_irq.cold kernel\/rcu\/tree.c:2590<br \/>\n  update_process_times kernel\/time\/timer.c:1953<br \/>\n  tick_sched_handle kernel\/time\/tick-sched.c:227<br \/>\n  tick_sched_timer kernel\/time\/tick-sched.c:1399<br \/>\n  __hrtimer_run_queues kernel\/time\/hrtimer.c:1652<br \/>\n  hrtimer_interrupt kernel\/time\/hrtimer.c:1717<br \/>\n  __sysvec_apic_timer_interrupt arch\/x86\/kernel\/apic\/apic.c:1113<br \/>\n  asm_call_irq_on_stack arch\/x86\/entry\/entry_64.S:808<\/p>\n<p>  netlink_attachskb net\/netlink\/af_netlink.c:1234<br \/>\n  netlink_unicast net\/netlink\/af_netlink.c:1349<br \/>\n  kauditd_send_queue kernel\/audit.c:776<br \/>\n  kauditd_thread kernel\/audit.c:897<br \/>\n  kthread kernel\/kthread.c:328<br \/>\n  ret_from_fork arch\/x86\/entry\/entry_64.S:304<\/p>\n<p>Restore the original behavior of the check which commit in Fixes<br \/>\naccidentally missed when restructuring the code.<\/p>\n<p>Found by Linux Verification Center (linuxtesting.org).<br \/>\n<br \/>\n<strong>Severity:<\/strong> 0.0 | NA<br \/>\n<br \/>\nVisit the link for more details, such as CVSS details, affected products, timeline, and more&#8230;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>CVE ID : CVE-2025-38727 Published : Sept. 4, 2025, 4:15 p.m. | 56\u00a0minutes ago Description : In the Linux kernel, the following vulnerability has been resolved: netlink: avoid infinite retry looping in netlink_unicast() netlink_attachskb() checks for the socket&#8217;s read memory allocation constraints. Firstly, it has: rmem sk_rcvbuf) to check if the just increased rmem value &hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-69502","post","type-post","status-publish","format-standard","hentry","category-vulnerability"],"_links":{"self":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/69502","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/comments?post=69502"}],"version-history":[{"count":0,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/69502\/revisions"}],"wp:attachment":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/media?parent=69502"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/categories?post=69502"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/tags?post=69502"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}