Hello, syzbot found the following issue on: HEAD commit: 93578a25 usb: musb: gadget: Use fallthrough pseudo-keyword git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing console output: https://syzkaller.appspot.com/x/log.txt?x=1480f19f900000 kernel config: https://syzkaller.appspot.com/x/.config?x=df3bb4023c36d114 dashboard link: https://syzkaller.appspot.com/bug?extid=431a2669cfb42d234b9c compiler: gcc (GCC) 10.1.0-syz 20200507 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+431a2669cfb42d234b9c@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: out-of-bounds in v4l2_fh_init+0x279/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25 Read of size 8 at addr ffff8881c72788c0 by task v4l_id/11388 CPU: 1 PID: 11388 Comm: v4l_id Not tainted 5.9.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x16e lib/dump_stack.c:118 print_address_description.constprop.0+0x1c/0x210 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x37/0x7c mm/kasan/report.c:530 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:2163 v4l2_open+0x20f/0x3d0 drivers/media/v4l2-core/v4l2-dev.c:423 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4b4/0x1090 fs/open.c:817 do_open fs/namei.c:3251 [inline] path_openat+0x190d/0x2690 fs/namei.c:3368 do_filp_open+0x17e/0x3c0 fs/namei.c:3395 do_sys_openat2+0x16d/0x420 fs/open.c:1168 do_sys_open fs/open.c:1184 [inline] __do_sys_open fs/open.c:1192 [inline] __se_sys_open fs/open.c:1188 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1188 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fee3e895840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007ffc37239888 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffc372399f8 RCX: 00007fee3e895840 RDX: 00007fee3e881ea0 RSI: 0000000000000000 RDI: 00007ffc37239f22 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000555d9d9f38d0 R13: 00007ffc372399f0 R14: 0000000000000000 R15: 0000000000000000 The buggy address belongs to the page: page:00000000914a1a5b refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1c7278 flags: 0x200000000000000() raw: 0200000000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881c7278780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881c7278800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881c7278880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff8881c7278900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881c7278980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
