================================================================== BUG: KASAN: vmalloc-out-of-bounds in fb_write_offset drivers/video/fbdev/core/sysmem.h:30 [inline] BUG: KASAN: vmalloc-out-of-bounds in fb_bitmap_2ppw drivers/video/fbdev/core/fb_imageblit.h:364 [inline] BUG: KASAN: vmalloc-out-of-bounds in fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:462 [inline] BUG: KASAN: vmalloc-out-of-bounds in fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline] BUG: KASAN: vmalloc-out-of-bounds in sys_imageblit+0xc28/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 Write of size 8 at addr ffff800093e39fc0 by task syz.8.1117/9967 CPU: 1 UID: 0 PID: 9967 Comm: syz.8.1117 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 print_address_description+0xb0/0x238 mm/kasan/report.c:378 print_report+0x68/0x84 mm/kasan/report.c:482 kasan_report+0x8c/0xc4 mm/kasan/report.c:595 __asan_report_store8_noabort+0x20/0x2c mm/kasan/report_generic.c:386 fb_write_offset drivers/video/fbdev/core/sysmem.h:30 [inline] fb_bitmap_2ppw drivers/video/fbdev/core/fb_imageblit.h:364 [inline] fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:462 [inline] fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline] sys_imageblit+0xc28/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 drm_fbdev_shmem_defio_imageblit+0x38/0x144 drivers/gpu/drm/drm_fbdev_shmem.c:39 cw_putcs_aligned drivers/video/fbdev/core/fbcon_cw.c:111 [inline] cw_putcs+0x69c/0x8bc drivers/video/fbdev/core/fbcon_cw.c:159 fbcon_putcs+0x258/0x390 drivers/video/fbdev/core/fbcon.c:1392 do_update_region+0x31c/0x3c8 drivers/tty/vt/vt.c:656 redraw_screen+0x388/0x51c drivers/tty/vt/vt.c:1008 vc_do_resize+0x884/0xbbc drivers/tty/vt/vt.c:1309 __vc_resize+0x60/0x74 drivers/tty/vt/vt.c:1331 vc_resize include/linux/vt_kern.h:49 [inline] fbcon_do_set_font+0x3d8/0x734 drivers/video/fbdev/core/fbcon.c:2435 fbcon_set_def_font+0x14c/0x240 drivers/video/fbdev/core/fbcon.c:2538 con_font_default drivers/tty/vt/vt.c:5016 [inline] con_font_op+0x654/0xc6c drivers/tty/vt/vt.c:5037 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline] vt_ioctl+0x1664/0x1d4c drivers/tty/vt/vt_ioctl.c:745 tty_ioctl+0x828/0xcb0 drivers/tty/tty_io.c:2792 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __arm64_sys_ioctl+0x154/0x1cc fs/ioctl.c:583 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x1 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 The buggy address belongs to a vmalloc virtual mapping Memory state around the buggy address: ffff800093e39e80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffff800093e39f00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 >ffff800093e39f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ ffff800093e3a000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffff800093e3a080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ================================================================== Unable to handle kernel paging request at virtual address ffff800093e39fc0 KASAN: probably user-memory-access in range [0x000000049f1cfe00-0x000000049f1cfe07] Mem abort info: ESR = 0x0000000096000047 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x07: level 3 translation fault Data abort info: ISV = 0, ISS = 0x00000047, ISS2 = 0x00000000 CM = 0, WnR = 1, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0 swapper pgtable: 4k pages, 48-bit VAs, pgdp=000000021b049000 [ffff800093e39fc0] pgd=0000000000000000, p4d=1000000221341003, pud=1000000221342003, pmd=1000000106e38403, pte=0000000000000000 Internal error: Oops: 0000000096000047 [#1] SMP Modules linked in: CPU: 0 UID: 0 PID: 9967 Comm: syz.8.1117 Tainted: G B L syzkaller #0 PREEMPT Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : fb_write_offset drivers/video/fbdev/core/sysmem.h:30 [inline] pc : fb_bitmap_2ppw drivers/video/fbdev/core/fb_imageblit.h:364 [inline] pc : fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:462 [inline] pc : fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline] pc : sys_imageblit+0xc30/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 lr : fb_write_offset drivers/video/fbdev/core/sysmem.h:30 [inline] lr : fb_bitmap_2ppw drivers/video/fbdev/core/fb_imageblit.h:364 [inline] lr : fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:462 [inline] lr : fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline] lr : sys_imageblit+0xc28/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 sp : ffff8000941e71c0 x29: ffff8000941e7240 x28: dfff800000000000 x27: ffff800093e38ff8 x26: ffff800093e39fc0 x25: ffff0000c35745f0 x24: 0000000000000004 x23: 0000000000000000 x22: ffff800093e39fc0 x21: 0000000000000000 x20: ffff0000c35745f1 x19: ffff8000941e7218 x18: 1fffe00034bb7428 x17: 0000000000000003 x16: ffff800088b37000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000080000 x9 : 0000000000000000 x8 : ffff0000d13857c0 x7 : 0000000000000000 x6 : ffff80008048c5b8 x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff8000802f62f4 x2 : 0000000000000000 x1 : ffff0000d13857c0 x0 : ffff800093e39fc0 Call trace: fb_bitmap_2ppw drivers/video/fbdev/core/fb_imageblit.h:365 [inline] (P) fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:462 [inline] (P) fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline] (P) sys_imageblit+0xc30/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 (P) drm_fbdev_shmem_defio_imageblit+0x38/0x144 drivers/gpu/drm/drm_fbdev_shmem.c:39 cw_putcs_aligned drivers/video/fbdev/core/fbcon_cw.c:111 [inline] cw_putcs+0x69c/0x8bc drivers/video/fbdev/core/fbcon_cw.c:159 fbcon_putcs+0x258/0x390 drivers/video/fbdev/core/fbcon.c:1392 do_update_region+0x31c/0x3c8 drivers/tty/vt/vt.c:656 redraw_screen+0x388/0x51c drivers/tty/vt/vt.c:1008 vc_do_resize+0x884/0xbbc drivers/tty/vt/vt.c:1309 __vc_resize+0x60/0x74 drivers/tty/vt/vt.c:1331 vc_resize include/linux/vt_kern.h:49 [inline] fbcon_do_set_font+0x3d8/0x734 drivers/video/fbdev/core/fbcon.c:2435 fbcon_set_def_font+0x14c/0x240 drivers/video/fbdev/core/fbcon.c:2538 con_font_default drivers/tty/vt/vt.c:5016 [inline] con_font_op+0x654/0xc6c drivers/tty/vt/vt.c:5037 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline] vt_ioctl+0x1664/0x1d4c drivers/tty/vt/vt_ioctl.c:745 tty_ioctl+0x828/0xcb0 drivers/tty/tty_io.c:2792 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __arm64_sys_ioctl+0x154/0x1cc fs/ioctl.c:583 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 Code: aa1a03e0 97b7a66d aa1a03e0 d34416e9 (f8008415) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: aa1a03e0 mov x0, x26 4: 97b7a66d bl 0xfffffffffede99b8 8: aa1a03e0 mov x0, x26 c: d34416e9 ubfx x9, x23, #4, #2 * 10: f8008415 str x21, [x0], #8 <-- trapping instruction