netlink: 4 bytes leftover after parsing attributes in process `syz.5.1260'. ================================================================== 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_bitblit drivers/video/fbdev/core/fb_imageblit.h:153 [inline] BUG: KASAN: vmalloc-out-of-bounds in fb_bitmap1x_imageblit drivers/video/fbdev/core/fb_imageblit.h:275 [inline] BUG: KASAN: vmalloc-out-of-bounds in fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:477 [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+0xffc/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 Write of size 8 at addr ffff800094119880 by task syz.5.1260/10644 CPU: 1 UID: 0 PID: 10644 Comm: syz.5.1260 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026 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_bitblit drivers/video/fbdev/core/fb_imageblit.h:153 [inline] fb_bitmap1x_imageblit drivers/video/fbdev/core/fb_imageblit.h:275 [inline] fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:477 [inline] fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline] sys_imageblit+0xffc/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 drm_fbdev_shmem_defio_imageblit+0x38/0x144 drivers/gpu/drm/drm_fbdev_shmem.c:39 soft_cursor+0x534/0x6bc drivers/video/fbdev/core/softcursor.c:74 bit_cursor+0xa8c/0x1138 drivers/video/fbdev/core/bitblit.c:372 fbcon_cursor+0x344/0x498 drivers/video/fbdev/core/fbcon.c:1410 set_cursor+0x1a0/0x200 drivers/tty/vt/vt.c:1010 con_flush_chars+0x84/0xc0 drivers/tty/vt/vt.c:3848 con_write+0x40/0x58 drivers/tty/vt/vt.c:3779 process_output_block drivers/tty/n_tty.c:557 [inline] n_tty_write+0x99c/0xde4 drivers/tty/n_tty.c:2366 iterate_tty_write drivers/tty/tty_io.c:1008 [inline] file_tty_write+0x3e0/0x6a0 drivers/tty/tty_io.c:1056 tty_write+0x44/0x54 drivers/tty/tty_io.c:1077 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x51c/0xa0c fs/read_write.c:687 ksys_write+0x12c/0x228 fs/read_write.c:739 __do_sys_write fs/read_write.c:750 [inline] __se_sys_write fs/read_write.c:747 [inline] __arm64_sys_write+0x84/0x98 fs/read_write.c:747 __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+0x60/0x1d8 arch/arm64/kernel/entry-common.c:797 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:816 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606 The buggy address belongs to a 0-page vmalloc region starting at 0xffff800093e19000 allocated at drm_gem_shmem_vmap_locked+0x45c/0x690 drivers/gpu/drm/drm_gem_shmem_helper.c:415 Memory state around the buggy address: ffff800094119780: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffff800094119800: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 >ffff800094119880: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ ffff800094119900: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffff800094119980: 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 ffff800094119880 KASAN: probably user-memory-access in range [0x00000004a08cc400-0x00000004a08cc407] 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=00000002193b5000 [ffff800094119880] pgd=0000000000000000, p4d=100000021f6f0003, pud=100000021f6f1003, pmd=1000000107743403, pte=0000000000000000 Internal error: Oops: 0000000096000047 [#1] SMP Modules linked in: CPU: 1 UID: 0 PID: 10644 Comm: syz.5.1260 Tainted: G B L syzkaller #0 PREEMPT Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026 pstate: 63400005 (nZCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : fb_write_offset drivers/video/fbdev/core/sysmem.h:30 [inline] pc : fb_bitblit drivers/video/fbdev/core/fb_imageblit.h:153 [inline] pc : fb_bitmap1x_imageblit drivers/video/fbdev/core/fb_imageblit.h:275 [inline] pc : fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:477 [inline] pc : fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline] pc : sys_imageblit+0x1018/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 lr : fb_write_offset drivers/video/fbdev/core/sysmem.h:30 [inline] lr : fb_bitblit drivers/video/fbdev/core/fb_imageblit.h:153 [inline] lr : fb_bitmap1x_imageblit drivers/video/fbdev/core/fb_imageblit.h:275 [inline] lr : fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:477 [inline] lr : fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline] lr : sys_imageblit+0xffc/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 sp : ffff8000958a7430 x29: ffff8000958a74b0 x28: 0000000000aaaaaa x27: 0000000000000020 x26: 0000000000000002 x25: 0000000000000007 x24: 0000000000000040 x23: ffff8000958a7490 x22: ffff800094119880 x21: ffff0000c745d08a x20: 00aaaaaa00000000 x19: 0000000000000020 x18: 1fffe000359d3e28 x17: 0000000000000003 x16: ffff8000898b7000 x15: 0000000000000000 x14: 0000000000002e34 x13: 0000000000000001 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000080000 x9 : 0000000000000001 x8 : 0000000000000040 x7 : 0000000000000000 x6 : ffff8000804a121c x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff80008030cfb4 x2 : 0000000000000000 x1 : ffff0000d7a00000 x0 : 0000000000000000 Call trace: fb_write_offset drivers/video/fbdev/core/sysmem.h:30 [inline] (P) fb_bitblit drivers/video/fbdev/core/fb_imageblit.h:153 [inline] (P) fb_bitmap1x_imageblit drivers/video/fbdev/core/fb_imageblit.h:275 [inline] (P) fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:477 [inline] (P) fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline] (P) sys_imageblit+0x1018/0x1758 drivers/video/fbdev/core/sysimgblt.c:24 (P) drm_fbdev_shmem_defio_imageblit+0x38/0x144 drivers/gpu/drm/drm_fbdev_shmem.c:39 soft_cursor+0x534/0x6bc drivers/video/fbdev/core/softcursor.c:74 bit_cursor+0xa8c/0x1138 drivers/video/fbdev/core/bitblit.c:372 fbcon_cursor+0x344/0x498 drivers/video/fbdev/core/fbcon.c:1410 set_cursor+0x1a0/0x200 drivers/tty/vt/vt.c:1010 con_flush_chars+0x84/0xc0 drivers/tty/vt/vt.c:3848 con_write+0x40/0x58 drivers/tty/vt/vt.c:3779 process_output_block drivers/tty/n_tty.c:557 [inline] n_tty_write+0x99c/0xde4 drivers/tty/n_tty.c:2366 iterate_tty_write drivers/tty/tty_io.c:1008 [inline] file_tty_write+0x3e0/0x6a0 drivers/tty/tty_io.c:1056 tty_write+0x44/0x54 drivers/tty/tty_io.c:1077 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x51c/0xa0c fs/read_write.c:687 ksys_write+0x12c/0x228 fs/read_write.c:739 __do_sys_write fs/read_write.c:750 [inline] __se_sys_write fs/read_write.c:747 [inline] __arm64_sys_write+0x84/0x98 fs/read_write.c:747 __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+0x60/0x1d8 arch/arm64/kernel/entry-common.c:797 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:816 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606 Code: 2a1f03e0 f81c83a9 1100075a 0b1b0268 (f90002d4) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 2a1f03e0 mov w0, wzr 4: f81c83a9 stur x9, [x29, #-56] 8: 1100075a add w26, w26, #0x1 c: 0b1b0268 add w8, w19, w27 * 10: f90002d4 str x20, [x22] <-- trapping instruction