================================================================== BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:663 [inline] BUG: KASAN: slab-out-of-bounds in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] BUG: KASAN: slab-out-of-bounds in bit_putcs+0xab7/0xc30 drivers/video/fbdev/core/bitblit.c:185 Read of size 1 at addr ffff88808b075443 by task syz-executor.2/27083 CPU: 1 PID: 27083 Comm: syz-executor.2 Not tainted 4.14.193-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load1_noabort+0x68/0x70 mm/kasan/report.c:427 __fb_pad_aligned_buffer include/linux/fb.h:663 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] bit_putcs+0xab7/0xc30 drivers/video/fbdev/core/bitblit.c:185 fbcon_putcs+0x2fe/0x480 drivers/video/fbdev/core/fbcon.c:1301 do_update_region+0x34b/0x5b0 drivers/tty/vt/vt.c:373 redraw_screen+0x56e/0x790 drivers/tty/vt/vt.c:705 vc_do_resize+0xc20/0xe30 drivers/tty/vt/vt.c:973 vt_ioctl+0x19f7/0x1ea0 drivers/tty/vt/vt_ioctl.c:901 tty_ioctl+0x50f/0x13c0 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45ce69 RSP: 002b:00007ff7ddae5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000001c340 RCX: 000000000045ce69 RDX: 0000000020000000 RSI: 000000000000560a RDI: 0000000000000006 RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffc27c83b4f R14: 00007ff7ddae69c0 R15: 000000000118bf2c Allocated by task 26785: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15a/0x400 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] fbcon_set_font+0x2fb/0x7c0 drivers/video/fbdev/core/fbcon.c:2621 con_font_set drivers/tty/vt/vt.c:4189 [inline] con_font_op+0xb69/0xf60 drivers/tty/vt/vt.c:4254 vt_ioctl+0xd91/0x1ea0 drivers/tty/vt/vt_ioctl.c:928 tty_ioctl+0x50f/0x13c0 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 7: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 sk_prot_free net/core/sock.c:1504 [inline] __sk_destruct+0x577/0x6e0 net/core/sock.c:1582 sk_destruct net/core/sock.c:1597 [inline] __sk_free+0xd9/0x2d0 net/core/sock.c:1605 sk_free+0x2b/0x40 net/core/sock.c:1616 deferred_put_nlk_sk+0xed/0x260 net/netlink/af_netlink.c:711 __rcu_reclaim kernel/rcu/rcu.h:195 [inline] rcu_do_batch kernel/rcu/tree.c:2699 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline] rcu_process_callbacks+0x780/0x1180 kernel/rcu/tree.c:2946 __do_softirq+0x254/0xa1d kernel/softirq.c:288 The buggy address belongs to the object at ffff88808b074c80 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 1987 bytes inside of 2048-byte region [ffff88808b074c80, ffff88808b075480) The buggy address belongs to the page: page:ffffea00022c1d00 count:1 mapcount:0 mapping:ffff88808b074400 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffff88808b074400 0000000000000000 0000000100000003 raw: ffffea00029ea520 ffffea0002829420 ffff88812fe52c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808b075300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808b075380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88808b075400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88808b075480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808b075500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================