syzbot


KASAN: use-after-free Write in hash_netport6_gc

Status: moderation: reported on 2024/02/07 00:08
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+5f387c4b7b490255e126@syzkaller.appspotmail.com
First crash: 76d, last: 76d

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: use-after-free in atomic_inc include/linux/atomic/atomic-instrumented.h:435 [inline]
BUG: KASAN: use-after-free in hash_netport6_gc+0x101/0x570 net/netfilter/ipset/ip_set_hash_gen.h:572
Write of size 4 at addr ffff888032a50004 by task kworker/0:6/5165

CPU: 0 PID: 5165 Comm: kworker/0:6 Not tainted 6.8.0-rc2-syzkaller-00199-g021533194476 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Workqueue: events_power_efficient hash_netport6_gc
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x167/0x540 mm/kasan/report.c:488
 kasan_report+0x142/0x180 mm/kasan/report.c:601
 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
 atomic_inc include/linux/atomic/atomic-instrumented.h:435 [inline]
 hash_netport6_gc+0x101/0x570 net/netfilter/ipset/ip_set_hash_gen.h:572
 process_one_work kernel/workqueue.c:2633 [inline]
 process_scheduled_works+0x915/0x1420 kernel/workqueue.c:2706
 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787
 kthread+0x2f1/0x390 kernel/kthread.c:388
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0000ca9400 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x32a50
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 ffffea000131de08 ffff8880b94428c0 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x552dc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_ZERO|__GFP_ACCOUNT), pid 12506, tgid 12503 (syz-executor.1), ts 973924056183, free_ts 973924212073
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533
 prep_new_page mm/page_alloc.c:1540 [inline]
 get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311
 __alloc_pages+0x255/0x680 mm/page_alloc.c:4567
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x91/0x1f0 mm/slub.c:3926
 __do_kmalloc_node mm/slub.c:3969 [inline]
 __kmalloc_node+0x339/0x4e0 mm/slub.c:3988
 kmalloc_node include/linux/slab.h:610 [inline]
 kvmalloc_node+0x72/0x190 mm/util.c:617
 hash_netport_create+0x35d/0x1050 net/netfilter/ipset/ip_set_hash_gen.h:1568
 ip_set_create+0xa5e/0x1780 net/netfilter/ipset/ip_set_core.c:1103
 nfnetlink_rcv_msg+0xbee/0x1190 net/netfilter/nfnetlink.c:302
 netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2543
 nfnetlink_rcv+0x294/0x2650 net/netfilter/nfnetlink.c:659
 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
 netlink_unicast+0x7ec/0x980 net/netlink/af_netlink.c:1367
 netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x223/0x270 net/socket.c:745
 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
 ___sys_sendmsg net/socket.c:2638 [inline]
 __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
page last free pid 12506 tgid 12503 stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1140 [inline]
 free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486
 folio_put include/linux/mm.h:1494 [inline]
 free_large_kmalloc+0x105/0x1c0 mm/slub.c:4380
 kfree+0x1be/0x380 mm/slub.c:4403
 hash_netport6_destroy+0x121/0x2c0 net/netfilter/ipset/ip_set_hash_gen.h:455
 ip_set_create+0x13b6/0x1780 net/netfilter/ipset/ip_set_core.c:1157
 nfnetlink_rcv_msg+0xbee/0x1190 net/netfilter/nfnetlink.c:302
 netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2543
 nfnetlink_rcv+0x294/0x2650 net/netfilter/nfnetlink.c:659
 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
 netlink_unicast+0x7ec/0x980 net/netlink/af_netlink.c:1367
 netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x223/0x270 net/socket.c:745
 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
 ___sys_sendmsg net/socket.c:2638 [inline]
 __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

Memory state around the buggy address:
 ffff888032a4ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888032a4ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888032a50000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888032a50080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888032a50100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/02/02 07:21 upstream 021533194476 d61103fc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: use-after-free Write in hash_netport6_gc
* Struck through repros no longer work on HEAD.