CVE-2024-35899

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> netfilter: nf_tables: flush pending destroy work before exit_net release<br /> <br /> Similar to 2c9f0293280e ("netfilter: nf_tables: flush pending destroy<br /> work before netlink notifier") to address a race between exit_net and<br /> the destroy workqueue.<br /> <br /> The trace below shows an element to be released via destroy workqueue<br /> while exit_net path (triggered via module removal) has already released<br /> the set that is used in such transaction.<br /> <br /> [ 1360.547789] BUG: KASAN: slab-use-after-free in nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]<br /> [ 1360.547861] Read of size 8 at addr ffff888140500cc0 by task kworker/4:1/152465<br /> [ 1360.547870] CPU: 4 PID: 152465 Comm: kworker/4:1 Not tainted 6.8.0+ #359<br /> [ 1360.547882] Workqueue: events nf_tables_trans_destroy_work [nf_tables]<br /> [ 1360.547984] Call Trace:<br /> [ 1360.547991] <br /> [ 1360.547998] dump_stack_lvl+0x53/0x70<br /> [ 1360.548014] print_report+0xc4/0x610<br /> [ 1360.548026] ? __virt_addr_valid+0xba/0x160<br /> [ 1360.548040] ? __pfx__raw_spin_lock_irqsave+0x10/0x10<br /> [ 1360.548054] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]<br /> [ 1360.548176] kasan_report+0xae/0xe0<br /> [ 1360.548189] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]<br /> [ 1360.548312] nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]<br /> [ 1360.548447] ? __pfx_nf_tables_trans_destroy_work+0x10/0x10 [nf_tables]<br /> [ 1360.548577] ? _raw_spin_unlock_irq+0x18/0x30<br /> [ 1360.548591] process_one_work+0x2f1/0x670<br /> [ 1360.548610] worker_thread+0x4d3/0x760<br /> [ 1360.548627] ? __pfx_worker_thread+0x10/0x10<br /> [ 1360.548640] kthread+0x16b/0x1b0<br /> [ 1360.548653] ? __pfx_kthread+0x10/0x10<br /> [ 1360.548665] ret_from_fork+0x2f/0x50<br /> [ 1360.548679] ? __pfx_kthread+0x10/0x10<br /> [ 1360.548690] ret_from_fork_asm+0x1a/0x30<br /> [ 1360.548707] <br /> <br /> [ 1360.548719] Allocated by task 192061:<br /> [ 1360.548726] kasan_save_stack+0x20/0x40<br /> [ 1360.548739] kasan_save_track+0x14/0x30<br /> [ 1360.548750] __kasan_kmalloc+0x8f/0xa0<br /> [ 1360.548760] __kmalloc_node+0x1f1/0x450<br /> [ 1360.548771] nf_tables_newset+0x10c7/0x1b50 [nf_tables]<br /> [ 1360.548883] nfnetlink_rcv_batch+0xbc4/0xdc0 [nfnetlink]<br /> [ 1360.548909] nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink]<br /> [ 1360.548927] netlink_unicast+0x367/0x4f0<br /> [ 1360.548935] netlink_sendmsg+0x34b/0x610<br /> [ 1360.548944] ____sys_sendmsg+0x4d4/0x510<br /> [ 1360.548953] ___sys_sendmsg+0xc9/0x120<br /> [ 1360.548961] __sys_sendmsg+0xbe/0x140<br /> [ 1360.548971] do_syscall_64+0x55/0x120<br /> [ 1360.548982] entry_SYSCALL_64_after_hwframe+0x55/0x5d<br /> <br /> [ 1360.548994] Freed by task 192222:<br /> [ 1360.548999] kasan_save_stack+0x20/0x40<br /> [ 1360.549009] kasan_save_track+0x14/0x30<br /> [ 1360.549019] kasan_save_free_info+0x3b/0x60<br /> [ 1360.549028] poison_slab_object+0x100/0x180<br /> [ 1360.549036] __kasan_slab_free+0x14/0x30<br /> [ 1360.549042] kfree+0xb6/0x260<br /> [ 1360.549049] __nft_release_table+0x473/0x6a0 [nf_tables]<br /> [ 1360.549131] nf_tables_exit_net+0x170/0x240 [nf_tables]<br /> [ 1360.549221] ops_exit_list+0x50/0xa0<br /> [ 1360.549229] free_exit_list+0x101/0x140<br /> [ 1360.549236] unregister_pernet_operations+0x107/0x160<br /> [ 1360.549245] unregister_pernet_subsys+0x1c/0x30<br /> [ 1360.549254] nf_tables_module_exit+0x43/0x80 [nf_tables]<br /> [ 1360.549345] __do_sys_delete_module+0x253/0x370<br /> [ 1360.549352] do_syscall_64+0x55/0x120<br /> [ 1360.549360] entry_SYSCALL_64_after_hwframe+0x55/0x5d<br /> <br /> (gdb) list *__nft_release_table+0x473<br /> 0x1e033 is in __nft_release_table (net/netfilter/nf_tables_api.c:11354).<br /> 11349 list_for_each_entry_safe(flowtable, nf, &amp;table-&gt;flowtables, list) {<br /> 11350 list_del(&amp;flowtable-&gt;list);<br /> 11351 nft_use_dec(&amp;table-&gt;use);<br /> 11352 nf_tables_flowtable_destroy(flowtable);<br /> 11353 }<br /> 11354 list_for_each_entry_safe(set, ns, &amp;table-&gt;sets, list) {<br /> 11355 list_del(&amp;set-&gt;list);<br /> 11356 nft_use_dec(&amp;table-&gt;use);<br /> 11357 if (set-&gt;flags &amp; (NFT_SET_MAP | NFT_SET_OBJECT))<br /> 11358 nft_map_deactivat<br /> ---truncated---