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BUG: KASAN: slab-out-of-bounds in ec168_i2c_xfer+0x4d4/0x630 drivers/media/usb/dvb-usb-v2/ec168.c:143
Read of size 1 at addr ffff88807ceb51a1 by task syz.0.17/6459

CPU: 0 UID: 0 PID: 6459 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 ec168_i2c_xfer+0x4d4/0x630 drivers/media/usb/dvb-usb-v2/ec168.c:143
 __i2c_transfer+0x7bf/0x1fd0 drivers/i2c/i2c-core-base.c:-1
 i2c_transfer+0x1cb/0x2d0 drivers/i2c/i2c-core-base.c:2396
 i2cdev_ioctl_rdwr+0x460/0x740 drivers/i2c/i2c-dev.c:306
 i2cdev_ioctl+0x6a5/0x880 drivers/i2c/i2c-dev.c:467
 vfs_ioctl fs/ioctl.c:52 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x102/0x490 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f82b299e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f82b3880028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f82b2c25fa0 RCX: 00007f82b299e159
RDX: 0000200000000200 RSI: 0000000000000707 RDI: 0000000000000004
RBP: 00007f82b2a35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f82b2c26038 R14: 00007f82b2c25fa0 R15: 00007ffef28fa518
 </TASK>

Allocated by task 6459:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:409 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5531 [inline]
 __kmalloc_node_track_caller_noprof+0x4b0/0x720 mm/slub.c:5662
 memdup_user+0x2b/0xd0 mm/util.c:221
 i2cdev_ioctl_rdwr+0x1c6/0x740 drivers/i2c/i2c-dev.c:266
 i2cdev_ioctl+0x6a5/0x880 drivers/i2c/i2c-dev.c:467
 vfs_ioctl fs/ioctl.c:52 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x102/0x490 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

The buggy address belongs to the object at ffff88807ceb51a0
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes to the right of
 allocated 1-byte region [ffff88807ceb51a0, ffff88807ceb51a1)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807ceb5280 pfn:0x7ceb5
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88813feb9500 ffffea0000a1d890 ffffea0000a70610
raw: ffff88807ceb5280 0000000000800078 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4985, tgid 4985 (udevadm), ts 25721906263
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1860
 prep_new_page mm/page_alloc.c:1868 [inline]
 get_page_from_freelist+0x2251/0x22d0 mm/page_alloc.c:3950
 __alloc_frozen_pages_noprof+0x211/0x440 mm/page_alloc.c:5492
 alloc_slab_page mm/slub.c:3384 [inline]
 allocate_slab+0x7d/0x5e0 mm/slub.c:3499
 new_slab mm/slub.c:3550 [inline]
 refill_objects+0x2d5/0x350 mm/slub.c:7539
 refill_sheaf mm/slub.c:2917 [inline]
 __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4811
 alloc_from_pcs mm/slub.c:4887 [inline]
 slab_alloc_node mm/slub.c:5021 [inline]
 __do_kmalloc_node mm/slub.c:5530 [inline]
 __kmalloc_noprof+0x476/0x720 mm/slub.c:5556
 _kmalloc_noprof include/linux/slab.h:995 [inline]
 kernfs_fop_write_iter+0x157/0x540 fs/kernfs/file.c:322
 new_sync_write fs/read_write.c:575 [inline]
 vfs_write+0x612/0xba0 fs/read_write.c:667
 ksys_write+0x150/0x270 fs/read_write.c:719
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x102/0x490 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
page last free pid 1 tgid 1 ts 22586207837 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1402 [inline]
 free_pages_prepare+0x9ae/0xa90 mm/page_alloc.c:1447
 __free_contig_range_common+0x174/0x340 mm/page_alloc.c:7123
 destroy_args+0x4e5/0x570 mm/debug_vm_pgtable.c:993
 debug_vm_pgtable+0x3f8/0x410 mm/debug_vm_pgtable.c:1368
 do_one_initcall+0x250/0x860 init/main.c:1419
 do_initcall_level+0x10a/0x1a0 init/main.c:1481
 do_initcalls+0x59/0xa0 init/main.c:1497
 kernel_init_freeable+0x29d/0x3e0 init/main.c:1732
 kernel_init+0x22/0x1d0 init/main.c:1622
 ret_from_fork+0x510/0xb60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88807ceb5080: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
 ffff88807ceb5100: fa fc fc fc fa fc fc fc 06 fc fc fc 00 fc fc fc
>ffff88807ceb5180: fa fc fc fc 01 fc fc fc fa fc fc fc fa fc fc fc
                               ^
 ffff88807ceb5200: fa fc fc fc fa fc fc fc fa fc fc fc 00 fc fc fc
 ffff88807ceb5280: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
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