Hello, syzbot found the following issue on: HEAD commit: e4c26faa Merge tag 'usb-5.9-rc5' of git://git.kernel.org/p.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=14d155f9900000 kernel config: https://syzkaller.appspot.com/x/.config?x=c61610091f4ca8c4 dashboard link: https://syzkaller.appspot.com/bug?extid=9381e25e04a6ea4f2a20 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+9381e25e04a6ea4f2a20@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-out-of-bounds in fbcon_redraw_softback drivers/video/fbdev/core/fbcon.c:1676 [inline] BUG: KASAN: slab-out-of-bounds in fbcon_scrolldelta+0x10da/0x1230 drivers/video/fbdev/core/fbcon.c:2909 Read of size 2 at addr ffff8881e9ae68c0 by task syz-executor.1/20692 CPU: 0 PID: 20692 Comm: syz-executor.1 Not tainted 5.9.0-rc4-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+0x198/0x1fd lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 fbcon_redraw_softback drivers/video/fbdev/core/fbcon.c:1676 [inline] fbcon_scrolldelta+0x10da/0x1230 drivers/video/fbdev/core/fbcon.c:2909 fbcon_set_origin+0x3c/0x50 drivers/video/fbdev/core/fbcon.c:2959 set_origin+0xe7/0x3e0 drivers/tty/vt/vt.c:930 vc_do_resize+0xb0f/0x1150 drivers/tty/vt/vt.c:1305 fbcon_modechanged+0x36c/0x710 drivers/video/fbdev/core/fbcon.c:3011 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3069 do_fb_ioctl+0x62e/0x690 drivers/video/fbdev/core/fbmem.c:1106 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1181 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5f9 Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f51ee9c6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000e0c0 RCX: 000000000045d5f9 RDX: 0000000020001180 RSI: 0000000000004601 RDI: 0000000000000003 RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007fffb40f07cf R14: 00007f51ee9c79c0 R15: 000000000118cf4c Allocated by task 3837: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 __do_kmalloc mm/slab.c:3655 [inline] __kmalloc+0x1b0/0x310 mm/slab.c:3664 kmalloc include/linux/slab.h:559 [inline] kzalloc include/linux/slab.h:666 [inline] vc_do_resize+0x2f6/0x1150 drivers/tty/vt/vt.c:1228 vt_resizex drivers/tty/vt/vt_ioctl.c:818 [inline] vt_ioctl+0xef0/0x2cc0 drivers/tty/vt/vt_ioctl.c:1036 tty_ioctl+0x1019/0x15f0 drivers/tty/tty_io.c:2656 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8881e9ae6000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 2240 bytes inside of 4096-byte region [ffff8881e9ae6000, ffff8881e9ae7000) The buggy address belongs to the page: page:00000000761e5aa4 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1e9ae6 head:00000000761e5aa4 order:1 compound_mapcount:0 flags: 0x57ffe0000010200(slab|head) raw: 057ffe0000010200 ffffea0007bbe508 ffffea0007bc1288 ffff8880aa040900 raw: 0000000000000000 ffff8881e9ae6000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881e9ae6780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881e9ae6800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881e9ae6880: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff8881e9ae6900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881e9ae6980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- 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. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
