================================================================== BUG: KASAN: use-after-free in v4l2_fh_init+0x279/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25 Read of size 8 at addr ffff888072c3c738 by task v4l_id/4208 CPU: 1 PID: 4208 Comm: v4l_id Not tainted 6.1.0-rc2-syzkaller-00063-g1a2dcbdde82e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15e/0x45d mm/kasan/report.c:395 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495 v4l2_fh_init+0x279/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25 v4l2_fh_open+0x88/0xc0 drivers/media/v4l2-core/v4l2-fh.c:63 em28xx_v4l2_open+0x11c/0x570 drivers/media/usb/em28xx/em28xx-video.c:2153 v4l2_open+0x21c/0x3f0 drivers/media/v4l2-core/v4l2-dev.c:427 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x6cc/0x13f0 fs/open.c:882 do_open fs/namei.c:3557 [inline] path_openat+0x1bf6/0x2860 fs/namei.c:3713 do_filp_open+0x1b6/0x400 fs/namei.c:3740 do_sys_openat2+0x16d/0x4c0 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_openat fs/open.c:1342 [inline] __se_sys_openat fs/open.c:1337 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fe91ab25697 Code: 25 00 00 41 00 3d 00 00 41 00 74 37 64 8b 04 25 18 00 00 00 85 c0 75 5b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 85 00 00 00 48 83 c4 68 5d 41 5c c3 0f 1f RSP: 002b:00007fff182ea980 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000056064d0bfc40 RCX: 00007fe91ab25697 RDX: 0000000000000000 RSI: 00007fff182eaf1f RDI: 00000000ffffff9c RBP: 00007fff182eaf1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3615: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:371 [inline] ____kasan_kmalloc mm/kasan/common.c:330 [inline] __kasan_kmalloc+0xa1/0xb0 mm/kasan/common.c:380 kmalloc include/linux/slab.h:576 [inline] kzalloc include/linux/slab.h:712 [inline] em28xx_v4l2_init drivers/media/usb/em28xx/em28xx-video.c:2532 [inline] em28xx_v4l2_init.cold+0x93/0x325c drivers/media/usb/em28xx/em28xx-video.c:2510 em28xx_init_extension+0x12f/0x1f0 drivers/media/usb/em28xx/em28xx-core.c:1116 request_module_async+0x5d/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3405 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Freed by task 3615: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2a/0x40 mm/kasan/generic.c:511 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xab/0x3b0 mm/slub.c:3674 kref_put.isra.0+0x6f/0xa0 include/linux/kref.h:65 em28xx_v4l2_init drivers/media/usb/em28xx/em28xx-video.c:2901 [inline] em28xx_v4l2_init.cold+0x263/0x325c drivers/media/usb/em28xx/em28xx-video.c:2510 em28xx_init_extension+0x12f/0x1f0 drivers/media/usb/em28xx/em28xx-core.c:1116 request_module_async+0x5d/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3405 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 The buggy address belongs to the object at ffff888072c3c000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 1848 bytes inside of 8192-byte region [ffff888072c3c000, ffff888072c3e000) The buggy address belongs to the physical page: page:ffffea0001cb0e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x72c38 head:ffffea0001cb0e00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001cb1200 dead000000000006 ffff888011842280 raw: 0000000000000000 0000000080020002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 3182, tgid 3182 (dhcpcd), ts 57703969118, free_ts 57699852398 prep_new_page mm/page_alloc.c:2538 [inline] get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4287 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5554 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2285 alloc_slab_page mm/slub.c:1794 [inline] allocate_slab+0x213/0x300 mm/slub.c:1939 new_slab mm/slub.c:1992 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3180 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3279 slab_alloc_node mm/slub.c:3364 [inline] __kmem_cache_alloc_node+0x191/0x3e0 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:954 [inline] __kmalloc_node_track_caller+0x45/0xc0 mm/slab_common.c:975 kmalloc_reserve net/core/skbuff.c:437 [inline] __alloc_skb+0xd9/0x2f0 net/core/skbuff.c:509 alloc_skb include/linux/skbuff.h:1267 [inline] netlink_dump+0x2c0/0xc20 net/netlink/af_netlink.c:2242 netlink_recvmsg+0xbdd/0xe50 net/netlink/af_netlink.c:2002 sock_recvmsg_nosec net/socket.c:995 [inline] sock_recvmsg net/socket.c:1013 [inline] sock_recvmsg net/socket.c:1009 [inline] ____sys_recvmsg+0x2c7/0x610 net/socket.c:2701 ___sys_recvmsg+0xf2/0x180 net/socket.c:2743 __sys_recvmsg+0xf0/0x1c0 net/socket.c:2773 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1458 [inline] free_pcp_prepare+0x65c/0xd90 mm/page_alloc.c:1508 free_unref_page_prepare mm/page_alloc.c:3386 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3482 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2586 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x62/0x80 mm/kasan/common.c:302 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:737 [inline] slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x2ac/0x3c0 mm/slub.c:3422 getname_flags.part.0+0x50/0x4f0 fs/namei.c:139 getname_flags+0x9a/0xe0 include/linux/audit.h:320 vfs_fstatat+0x73/0xb0 fs/stat.c:266 __do_sys_newfstatat+0x94/0x120 fs/stat.c:437 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888072c3c600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888072c3c680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888072c3c700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888072c3c780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888072c3c800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================