syzkaller1: entered promiscuous mode syzkaller1: entered allmulticast mode ================================================================== BUG: KASAN: global-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:641 [inline] BUG: KASAN: global-out-of-bounds in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:95 [inline] BUG: KASAN: global-out-of-bounds in bit_putcs+0x14d9/0x1bc0 drivers/video/fbdev/core/bitblit.c:201 Read of size 1 at addr ffffffff8bc33349 by task syz.8.1855/15418 CPU: 1 UID: 0 PID: 15418 Comm: syz.8.1855 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __fb_pad_aligned_buffer include/linux/fb.h:641 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:95 [inline] bit_putcs+0x14d9/0x1bc0 drivers/video/fbdev/core/bitblit.c:201 fbcon_putcs+0x3a6/0x580 drivers/video/fbdev/core/fbcon.c:1320 do_update_region+0x21c/0x440 drivers/tty/vt/vt.c:618 update_region+0x1ce/0x490 drivers/tty/vt/vt.c:642 vcs_write+0xd65/0x1260 drivers/tty/vt/vc_screen.c:685 do_loop_readv_writev fs/read_write.c:850 [inline] vfs_writev+0x4b6/0x960 fs/read_write.c:1059 do_writev+0x14d/0x2d0 fs/read_write.c:1103 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb9c0f8eec9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb9c1d42038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007fb9c11e5fa0 RCX: 00007fb9c0f8eec9 RDX: 0000000000000007 RSI: 0000200000000c40 RDI: 000000000000000a RBP: 00007fb9c1011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb9c11e6038 R14: 00007fb9c11e5fa0 R15: 00007fffb621cdf8 The buggy address belongs to the variable: .str.17+0x9/0x20 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xbc33 flags: 0xfff00000002000(reserved|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000002000 ffffea00002f0cc8 ffffea00002f0cc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner info is not present (never set?) Memory state around the buggy address: ffffffff8bc33200: 03 f9 f9 f9 03 f9 f9 f9 00 00 00 00 03 f9 f9 f9 ffffffff8bc33280: 00 07 f9 f9 00 07 f9 f9 00 06 f9 f9 06 f9 f9 f9 >ffffffff8bc33300: 00 06 f9 f9 07 f9 f9 f9 00 01 f9 f9 00 00 f9 f9 ^ ffffffff8bc33380: 00 00 06 f9 f9 f9 f9 f9 06 f9 f9 f9 05 f9 f9 f9 ffffffff8bc33400: 00 00 00 00 00 00 00 00 00 00 00 00 06 f9 f9 f9 ==================================================================