Code: Unable to access opcode bytes at 0x7f11e138d13f.
RSP: 002b:00007ffc4ed1cd18 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f11e138d169
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffc4ed1cd7c R08: 0000000b4ed1ce0f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000007
R13: 00000000000927c0 R14: 000000000002744e R15: 00007ffc4ed1cdd0
 </TASK>
==================================================================
BUG: KASAN: slab-use-after-free in vidtv_mux_pid_ctx_init drivers/media/test-drivers/vidtv/vidtv_mux.c:78 [inline]
BUG: KASAN: slab-use-after-free in vidtv_mux_init+0xac2/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:524
Read of size 8 at addr ffff88802f46fb0c by task syz.2.35/6069

CPU: 0 UID: 0 PID: 6069 Comm: syz.2.35 Not tainted 6.14.0-rc5-syzkaller-00039-g848e07631744 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xc3/0x670 mm/kasan/report.c:521
 kasan_report+0xd9/0x110 mm/kasan/report.c:634
 vidtv_mux_pid_ctx_init drivers/media/test-drivers/vidtv/vidtv_mux.c:78 [inline]
 vidtv_mux_init+0xac2/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:524
 vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 [inline]
 vidtv_start_feed+0x334/0x4c0 drivers/media/test-drivers/vidtv/vidtv_bridge.c:239
 dmx_section_feed_start_filtering+0x3a5/0x660 drivers/media/dvb-core/dvb_demux.c:973
 dvb_dmxdev_feed_start drivers/media/dvb-core/dmxdev.c:508 [inline]
 dvb_dmxdev_feed_restart.isra.0+0x457/0x530 drivers/media/dvb-core/dmxdev.c:537
 dvb_dmxdev_filter_stop+0x2b4/0x3a0 drivers/media/dvb-core/dmxdev.c:564
 dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:840 [inline]
 dvb_demux_release+0x92/0x550 drivers/media/dvb-core/dmxdev.c:1246
 __fput+0x3ff/0xb70 fs/file_table.c:464
 task_work_run+0x14e/0x250 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xad8/0x2d70 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1096
 x64_sys_call+0x151f/0x1720 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f11e138d169
Code: Unable to access opcode bytes at 0x7f11e138d13f.
RSP: 002b:00007ffc4ed1cd18 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f11e138d169
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffc4ed1cd7c R08: 0000000b4ed1ce0f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000007
R13: 00000000000927c0 R14: 000000000002744e R15: 00007ffc4ed1cdd0
 </TASK>

Allocated by task 6069:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kmalloc_noprof include/linux/slab.h:901 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 vidtv_psi_pat_table_init+0x46/0x2c0 drivers/media/test-drivers/vidtv/vidtv_psi.c:970
 vidtv_channel_si_init+0x67/0x1a90 drivers/media/test-drivers/vidtv/vidtv_channel.c:423
 vidtv_mux_init+0x526/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:519
 vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 [inline]
 vidtv_start_feed+0x334/0x4c0 drivers/media/test-drivers/vidtv/vidtv_bridge.c:239
 dmx_section_feed_start_filtering+0x3a5/0x660 drivers/media/dvb-core/dvb_demux.c:973
 dvb_dmxdev_feed_start drivers/media/dvb-core/dmxdev.c:508 [inline]
 dvb_dmxdev_feed_restart.isra.0+0x457/0x530 drivers/media/dvb-core/dmxdev.c:537
 dvb_dmxdev_filter_stop+0x2b4/0x3a0 drivers/media/dvb-core/dmxdev.c:564
 dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:840 [inline]
 dvb_demux_release+0x92/0x550 drivers/media/dvb-core/dmxdev.c:1246
 __fput+0x3ff/0xb70 fs/file_table.c:464
 task_work_run+0x14e/0x250 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xad8/0x2d70 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1096
 x64_sys_call+0x151f/0x1720 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6069:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4609 [inline]
 kfree+0x2c4/0x4d0 mm/slub.c:4757
 vidtv_channel_si_init+0x34a/0x1a90 drivers/media/test-drivers/vidtv/vidtv_channel.c:499
 vidtv_mux_init+0x526/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:519
 vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 [inline]
 vidtv_start_feed+0x334/0x4c0 drivers/media/test-drivers/vidtv/vidtv_bridge.c:239
 dmx_section_feed_start_filtering+0x3a5/0x660 drivers/media/dvb-core/dvb_demux.c:973
 dvb_dmxdev_feed_start drivers/media/dvb-core/dmxdev.c:508 [inline]
 dvb_dmxdev_feed_restart.isra.0+0x457/0x530 drivers/media/dvb-core/dmxdev.c:537
 dvb_dmxdev_filter_stop+0x2b4/0x3a0 drivers/media/dvb-core/dmxdev.c:564
 dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:840 [inline]
 dvb_demux_release+0x92/0x550 drivers/media/dvb-core/dmxdev.c:1246
 __fput+0x3ff/0xb70 fs/file_table.c:464
 task_work_run+0x14e/0x250 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xad8/0x2d70 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1096
 x64_sys_call+0x151f/0x1720 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802f46fb00
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 12 bytes inside of
 freed 32-byte region [ffff88802f46fb00, ffff88802f46fb20)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2f46f
ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801b041780 ffffea0000c05800 dead000000000003
raw: 0000000000000000 0000000080400040 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 0x52800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP), pid 3235, tgid 3235 (kworker/u8:0), ts 18380791081, free_ts 17591456430
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1551
 prep_new_page mm/page_alloc.c:1559 [inline]
 get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3477
 __alloc_frozen_pages_noprof+0x221/0x2470 mm/page_alloc.c:4739
 alloc_pages_mpol+0x1fc/0x540 mm/mempolicy.c:2270
 alloc_slab_page mm/slub.c:2423 [inline]
 allocate_slab mm/slub.c:2587 [inline]
 new_slab+0x23d/0x330 mm/slub.c:2640
 ___slab_alloc+0xc5d/0x1720 mm/slub.c:3826
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3916
 __slab_alloc_node mm/slub.c:3991 [inline]
 slab_alloc_node mm/slub.c:4152 [inline]
 __kmalloc_cache_noprof+0xfa/0x410 mm/slub.c:4320
 kmalloc_noprof include/linux/slab.h:901 [inline]
 slab_free_hook mm/slub.c:2305 [inline]
 slab_free mm/slub.c:4609 [inline]
 kmem_cache_free+0x14e/0x4d0 mm/slub.c:4711
 __cleanup_sighand kernel/fork.c:1847 [inline]
 __cleanup_sighand+0x73/0xa0 kernel/fork.c:1839
 __exit_signal kernel/exit.c:211 [inline]
 release_task+0xd2c/0x1b00 kernel/exit.c:257
 exit_notify kernel/exit.c:775 [inline]
 do_exit+0x16ca/0x2d70 kernel/exit.c:958
 call_usermodehelper_exec_async+0x379/0x4c0 kernel/umh.c:122
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
page last free pid 977 tgid 977 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_frozen_pages+0x6db/0xfb0 mm/page_alloc.c:2660
 vfree+0x174/0x950 mm/vmalloc.c:3383
 delayed_vfree_work+0x56/0x70 mm/vmalloc.c:3303
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff88802f46fa00: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
 ffff88802f46fa80: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88802f46fb00: fa fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
                      ^
 ffff88802f46fb80: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
 ffff88802f46fc00: fa fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
==================================================================