================================================================== 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+0x1104/0x1d40 drivers/video/fbdev/core/sysimgblt.c:24 Write of size 8 at addr ffff80008fac9140 by task syz.6.2829/12618 CPU: 0 UID: 0 PID: 12618 Comm: syz.6.2829 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: linux,dummy-virt (DT) Call trace: show_stack+0x18/0x24 arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x7c/0xb0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x18c/0x4e8 mm/kasan/report.c:482 kasan_report+0xb8/0x218 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+0x1104/0x1d40 drivers/video/fbdev/core/sysimgblt.c:24 drm_fbdev_shmem_defio_imageblit+0x1c/0x120 drivers/gpu/drm/drm_fbdev_shmem.c:39 soft_cursor+0x40c/0x960 drivers/video/fbdev/core/softcursor.c:74 bit_cursor+0x8e0/0x1604 drivers/video/fbdev/core/bitblit.c:370 fbcon_cursor+0x304/0x440 drivers/video/fbdev/core/fbcon.c:1433 set_cursor drivers/tty/vt/vt.c:896 [inline] set_cursor+0x144/0x1a4 drivers/tty/vt/vt.c:887 con_flush_chars drivers/tty/vt/vt.c:3734 [inline] con_write+0x9c/0xcc drivers/tty/vt/vt.c:3665 process_output_block drivers/tty/n_tty.c:557 [inline] n_tty_write+0x2e8/0xbb0 drivers/tty/n_tty.c:2366 iterate_tty_write drivers/tty/tty_io.c:1008 [inline] file_tty_write.isra.0+0x294/0x690 drivers/tty/tty_io.c:1056 tty_write+0x30/0x50 drivers/tty/tty_io.c:1077 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x5b4/0xcd0 fs/read_write.c:687 ksys_write+0xf0/0x1e0 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+0x70/0xa0 fs/read_write.c:747 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x74/0x240 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:121 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:140 el0_svc+0x58/0x21c arch/arm64/kernel/entry-common.c:796 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:815 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606 The buggy address belongs to a vmalloc virtual mapping Memory state around the buggy address: ffff80008fac9000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffff80008fac9080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 >ffff80008fac9100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ ffff80008fac9180: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffff80008fac9200: 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 ffff80008fac9140 KASAN: probably user-memory-access in range [0x000000047d648a00-0x000000047d648a07] 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=0000000048258000 [ffff80008fac9140] pgd=0000000000000000, p4d=100000004e96e003, pud=100000004e96f003, pmd=1000000053c29403, pte=0000000000000000 Internal error: Oops: 0000000096000047 [#1] SMP Modules linked in: CPU: 0 UID: 0 PID: 12618 Comm: syz.6.2829 Tainted: G B L syzkaller #0 PREEMPT Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP Hardware name: linux,dummy-virt (DT) pstate: 40000005 (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+0xda8/0x1d40 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+0x1104/0x1d40 drivers/video/fbdev/core/sysimgblt.c:24 sp : ffff8000a0267450 x29: ffff8000a0267530 x28: ffff8000a02674d0 x27: 0000000000000004 x26: ffff80008fac9140 x25: ffff80008fac9140 x24: ffff0000157e41a8 x23: 1ffff0001404ce96 x22: 0000000000000004 x21: 0000000000000000 x20: dfff800000000000 x19: ffff0000157e41a9 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: ffff80008839a918 x14: 1ffff00011073523 x13: 0000000000012f00 x12: ffff7000113e9f11 x11: 1ffff000113e9f10 x10: ffff7000113e9f10 x9 : dfff800000000000 x8 : ffff800089f4f887 x7 : 0000000000000001 x6 : ffff7000113e9f10 x5 : ffff800089f4f880 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : ffff00000f3f0000 x0 : 0000000000000001 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+0xda8/0x1d40 drivers/video/fbdev/core/sysimgblt.c:24 (P) drm_fbdev_shmem_defio_imageblit+0x1c/0x120 drivers/gpu/drm/drm_fbdev_shmem.c:39 soft_cursor+0x40c/0x960 drivers/video/fbdev/core/softcursor.c:74 bit_cursor+0x8e0/0x1604 drivers/video/fbdev/core/bitblit.c:370 fbcon_cursor+0x304/0x440 drivers/video/fbdev/core/fbcon.c:1433 set_cursor drivers/tty/vt/vt.c:896 [inline] set_cursor+0x144/0x1a4 drivers/tty/vt/vt.c:887 con_flush_chars drivers/tty/vt/vt.c:3734 [inline] con_write+0x9c/0xcc drivers/tty/vt/vt.c:3665 process_output_block drivers/tty/n_tty.c:557 [inline] n_tty_write+0x2e8/0xbb0 drivers/tty/n_tty.c:2366 iterate_tty_write drivers/tty/tty_io.c:1008 [inline] file_tty_write.isra.0+0x294/0x690 drivers/tty/tty_io.c:1056 tty_write+0x30/0x50 drivers/tty/tty_io.c:1077 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x5b4/0xcd0 fs/read_write.c:687 ksys_write+0xf0/0x1e0 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+0x70/0xa0 fs/read_write.c:747 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x74/0x240 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:121 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:140 el0_svc+0x58/0x21c arch/arm64/kernel/entry-common.c:796 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:815 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606 Code: d343ff40 38f46800 35001ac0 d34416a2 (f9000344) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: d343ff40 lsr x0, x26, #3 4: 38f46800 ldrsb w0, [x0, x20] 8: 35001ac0 cbnz w0, 0x360 c: d34416a2 ubfx x2, x21, #4, #2 * 10: f9000344 str x4, [x26] <-- trapping instruction