================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:373 [inline] BUG: KASAN: slab-out-of-bounds in fbcon_get_font+0x2f4/0x6f0 drivers/video/fbdev/core/fbcon.c:2446 Read of size 9 at addr ffff88809f9bd08d by task syz-executor.2/10291 CPU: 0 PID: 10291 Comm: syz-executor.2 Not tainted 4.19.135-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+0x1fc/0x2fe lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1c7 mm/kasan/report.c:354 kasan_report+0x8f/0x96 mm/kasan/report.c:412 memcpy+0x20/0x50 mm/kasan/kasan.c:302 memcpy include/linux/string.h:373 [inline] fbcon_get_font+0x2f4/0x6f0 drivers/video/fbdev/core/fbcon.c:2446 con_font_get drivers/tty/vt/vt.c:4444 [inline] con_font_op+0x1f7/0x10e0 drivers/tty/vt/vt.c:4603 vt_ioctl+0x116d/0x24d0 drivers/tty/vt/vt_ioctl.c:928 tty_ioctl+0x5b0/0x15c0 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c369 Code: 8d b6 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 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f8d46460c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000001ba00 RCX: 000000000045c369 RDX: 0000000020000040 RSI: 0000000000004b60 RDI: 0000000000000003 RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007ffde6652a0f R14: 00007f8d464619c0 R15: 000000000078bf0c Allocated by task 9383: __do_kmalloc mm/slab.c:3727 [inline] __kmalloc+0x15a/0x3c0 mm/slab.c:3736 kmalloc include/linux/slab.h:520 [inline] fbcon_set_font+0x34f/0x8a0 drivers/video/fbdev/core/fbcon.c:2644 con_font_set drivers/tty/vt/vt.c:4536 [inline] con_font_op+0xd02/0x10e0 drivers/tty/vt/vt.c:4601 vt_ioctl+0x116d/0x24d0 drivers/tty/vt/vt_ioctl.c:928 tty_ioctl+0x5b0/0x15c0 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 skb_free_head net/core/skbuff.c:554 [inline] skb_release_data+0x6de/0x920 net/core/skbuff.c:574 skb_release_all net/core/skbuff.c:631 [inline] __kfree_skb net/core/skbuff.c:645 [inline] kfree_skb+0x11a/0x3d0 net/core/skbuff.c:663 __netif_receive_skb_core+0x535/0x3270 net/core/dev.c:4928 __netif_receive_skb_one_core+0xae/0x180 net/core/dev.c:4952 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5066 process_backlog+0x239/0x6f0 net/core/dev.c:5848 napi_poll net/core/dev.c:6271 [inline] net_rx_action+0x4ac/0xfb0 net/core/dev.c:6337 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292 The buggy address belongs to the object at ffff88809f9bcd80 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 781 bytes inside of 1024-byte region [ffff88809f9bcd80, ffff88809f9bd180) The buggy address belongs to the page: page:ffffea00027e6f00 count:1 mapcount:0 mapping:ffff88812c39cac0 index:0xffff88809f9bd200 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffffea00023e9d08 ffffea0002803e88 ffff88812c39cac0 raw: ffff88809f9bd200 ffff88809f9bc000 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809f9bcf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88809f9bd000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88809f9bd080: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809f9bd100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809f9bd180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================