================================================================== BUG: KASAN: slab-use-after-free in dvb_device_open+0xca/0x370 drivers/media/dvb-core/dvbdev.c:99 Read of size 8 at addr ffff888026013a18 by task syz.1.739/8652 CPU: 0 PID: 8652 Comm: syz.1.739 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 dvb_device_open+0xca/0x370 drivers/media/dvb-core/dvbdev.c:99 chrdev_open+0x5cc/0x6a0 fs/char_dev.c:414 do_dentry_open+0x8c6/0x1500 fs/open.c:929 do_open fs/namei.c:3640 [inline] path_openat+0x27f1/0x3230 fs/namei.c:3797 do_filp_open+0x1f5/0x430 fs/namei.c:3824 do_sys_openat2+0x134/0x1d0 fs/open.c:1421 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1447 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f13c695cfce Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007f13c77a8b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f13c77a96c0 RCX: 00007f13c695cfce RDX: 0000000000000002 RSI: 00007f13c77a8c00 RDI: ffffffffffffff9c RBP: 00007f13c77a8c00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd R13: 00007f13c6c16128 R14: 00007f13c6c16090 R15: 00007ffde36a77c8 Allocated by task 8397: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] __sta_info_destroy_part2+0x26f/0x420 net/mac80211/sta_info.c:1480 __sta_info_flush+0x3e5/0x4f0 net/mac80211/sta_info.c:1624 sta_info_flush net/mac80211/sta_info.h:913 [inline] ieee80211_ibss_disconnect+0x262/0x700 net/mac80211/ibss.c:698 ieee80211_ibss_leave+0x25/0x140 net/mac80211/ibss.c:1872 rdev_leave_ibss net/wireless/rdev-ops.h:573 [inline] __cfg80211_leave_ibss+0x1d2/0x400 net/wireless/ibss.c:210 cfg80211_leave_ibss+0x5e/0x80 net/wireless/ibss.c:228 cfg80211_change_iface+0x511/0xf30 net/wireless/util.c:1191 nl80211_set_interface+0x5f1/0x840 net/wireless/nl80211.c:4261 genl_family_rcv_msg_doit+0x211/0x310 net/netlink/genetlink.c:971 genl_family_rcv_msg net/netlink/genetlink.c:1051 [inline] genl_rcv_msg+0x619/0x7a0 net/netlink/genetlink.c:1066 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1075 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648 __sys_sendmsg net/socket.c:2677 [inline] __do_sys_sendmsg net/socket.c:2686 [inline] __se_sys_sendmsg+0x1c2/0x2b0 net/socket.c:2684 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 8397: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1e0 mm/slub.c:3843 __sta_info_destroy_part2+0x327/0x420 net/mac80211/sta_info.c:1493 __sta_info_flush+0x3e5/0x4f0 net/mac80211/sta_info.c:1624 sta_info_flush net/mac80211/sta_info.h:913 [inline] ieee80211_ibss_disconnect+0x262/0x700 net/mac80211/ibss.c:698 ieee80211_ibss_leave+0x25/0x140 net/mac80211/ibss.c:1872 rdev_leave_ibss net/wireless/rdev-ops.h:573 [inline] __cfg80211_leave_ibss+0x1d2/0x400 net/wireless/ibss.c:210 cfg80211_leave_ibss+0x5e/0x80 net/wireless/ibss.c:228 cfg80211_change_iface+0x511/0xf30 net/wireless/util.c:1191 nl80211_set_interface+0x5f1/0x840 net/wireless/nl80211.c:4261 genl_family_rcv_msg_doit+0x211/0x310 net/netlink/genetlink.c:971 genl_family_rcv_msg net/netlink/genetlink.c:1051 [inline] genl_rcv_msg+0x619/0x7a0 net/netlink/genetlink.c:1066 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1075 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648 __sys_sendmsg net/socket.c:2677 [inline] __do_sys_sendmsg net/socket.c:2686 [inline] __se_sys_sendmsg+0x1c2/0x2b0 net/socket.c:2684 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888026013a00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 24 bytes inside of freed 256-byte region [ffff888026013a00, ffff888026013b00) The buggy address belongs to the physical page: page:ffffea0000980480 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26012 head:ffffea0000980480 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017c41b40 ffffea0000b1b400 0000000000000007 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 11435852276, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4486 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2120 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] bus_add_driver+0x162/0x630 drivers/base/bus.c:659 driver_register+0x23a/0x310 drivers/base/driver.c:246 i2c_register_driver+0xba/0x160 drivers/i2c/i2c-core-base.c:2016 do_one_initcall+0x242/0x790 init/main.c:1250 do_initcall_level+0x137/0x1f0 init/main.c:1312 do_initcalls+0x69/0xd0 init/main.c:1328 kernel_init_freeable+0x3ed/0x580 init/main.c:1565 page_owner free stack trace missing Memory state around the buggy address: ffff888026013900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888026013980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888026013a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888026013a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888026013b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================