Hello, syzbot found the following issue on: HEAD commit: c912bf709078 Merge remote-tracking branches 'origin/arm64-.. git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=13b495bd980000 kernel config: https://syzkaller.appspot.com/x/.config?x=35545feca25ede03 dashboard link: https://syzkaller.appspot.com/bug?extid=793cf822d213be1a74f2 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/caeac6485006/disk-c912bf70.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/501c87f28da9/vmlinux-c912bf70.xz kernel image: https://storage.googleapis.com/syzbot-assets/6812e99b7182/Image-c912bf70.gz.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+793cf822d213be1a74f2@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: global-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:633 [inline] BUG: KASAN: global-out-of-bounds in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] BUG: KASAN: global-out-of-bounds in bit_putcs+0x9b8/0xe30 drivers/video/fbdev/core/bitblit.c:185 Read of size 1 at addr ffff80008b830d80 by task syz.1.1270/10828 CPU: 0 PID: 10828 Comm: syz.1.1270 Not tainted 6.10.0-rc7-syzkaller-gc912bf709078 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:317 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0x198/0x538 mm/kasan/report.c:488 kasan_report+0xd8/0x138 mm/kasan/report.c:601 __asan_report_load1_noabort+0x20/0x2c mm/kasan/report_generic.c:378 __fb_pad_aligned_buffer include/linux/fb.h:633 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] bit_putcs+0x9b8/0xe30 drivers/video/fbdev/core/bitblit.c:185 fbcon_putcs+0x318/0x4e8 drivers/video/fbdev/core/fbcon.c:1288 do_update_region+0x1e8/0x3d0 drivers/tty/vt/vt.c:609 update_region+0x1e0/0x478 drivers/tty/vt/vt.c:633 vcs_write+0x90c/0x10c8 drivers/tty/vt/vc_screen.c:698 do_loop_readv_writev fs/read_write.c:764 [inline] vfs_writev+0x5c8/0xb80 fs/read_write.c:973 do_writev+0x178/0x304 fs/read_write.c:1018 __do_sys_writev fs/read_write.c:1091 [inline] __se_sys_writev fs/read_write.c:1088 [inline] __arm64_sys_writev+0x80/0x94 fs/read_write.c:1088 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:131 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:150 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 The buggy address belongs to the variable: oid_data+0x340/0x3a0 The buggy address belongs to the virtual mapping at [ffff80008b260000, ffff80008ee20000) created by: declare_kernel_vmas+0x58/0xb8 arch/arm64/mm/mmu.c:770 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1a9430 flags: 0x5ffc00000002000(reserved|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000002000 fffffdffc5a50c08 fffffdffc5a50c08 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff80008b830c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff80008b830d00: 00 00 00 07 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 >ffff80008b830d80: f9 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 06 f9 f9 f9 ^ ffff80008b830e00: 05 f9 f9 f9 06 f9 f9 f9 00 00 00 00 00 00 00 00 ffff80008b830e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 02 f9 f9 ================================================================== --- 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. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup