================================================================== BUG: KASAN: slab-use-after-free in sg_release+0x2a4/0x2e0 drivers/scsi/sg.c:397 Read of size 4 at addr ffff888076e54948 by task syz.3.23/6657 CPU: 0 UID: 0 PID: 6657 Comm: syz.3.23 Not tainted 6.12.0-rc7-syzkaller-00189-ge8bdb3c8be08 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 sg_release+0x2a4/0x2e0 drivers/scsi/sg.c:397 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f112717e719 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffcbb633948 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f1127337a80 RCX: 00007f112717e719 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f1127337a80 R08: 0000000000000000 R09: 00007ffcbb633c3f R10: 000000000003fdc8 R11: 0000000000000246 R12: 000000000001efb7 R13: 00007ffcbb633a50 R14: 0000000000000032 R15: ffffffffffffffff Allocated by task 80: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:257 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4295 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] sg_alloc drivers/scsi/sg.c:1444 [inline] sg_add_device+0x139/0xb10 drivers/scsi/sg.c:1518 device_add+0xa1f/0xbf0 drivers/base/core.c:3695 scsi_sysfs_add_sdev+0x306/0x5a0 drivers/scsi/scsi_sysfs.c:1435 scsi_sysfs_add_devices drivers/scsi/scsi_scan.c:1896 [inline] scsi_finish_async_scan drivers/scsi/scsi_scan.c:1981 [inline] do_scan_async+0x42a/0x7a0 drivers/scsi/scsi_scan.c:2024 async_run_entry_fn+0xa8/0x420 kernel/async.c:129 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 6514: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kfree+0x1a0/0x440 mm/slub.c:4727 kref_put include/linux/kref.h:65 [inline] sg_remove_sfp_usercontext+0x331/0x4d0 drivers/scsi/sg.c:2238 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff888076e54800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 328 bytes inside of freed 512-byte region [ffff888076e54800, ffff888076e54a00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x76e54 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac41c80 ffffea0000d2c300 0000000000000002 raw: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac41c80 ffffea0000d2c300 0000000000000002 head: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 00fff00000000002 ffffea0001db9501 ffffffffffffffff 0000000000000000 head: ffff888000000004 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5213, tgid 5213 (udevd), ts 112460347081, free_ts 112282881880 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0x3649/0x3790 mm/page_alloc.c:3474 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4750 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_slab_page+0x6a/0x140 mm/slub.c:2412 allocate_slab+0x5a/0x2f0 mm/slub.c:2578 new_slab mm/slub.c:2631 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3818 __slab_alloc+0x58/0xa0 mm/slub.c:3908 __slab_alloc_node mm/slub.c:3961 [inline] slab_alloc_node mm/slub.c:4122 [inline] __kmalloc_cache_noprof+0x1d5/0x2c0 mm/slub.c:4290 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] kernfs_fop_open+0x3e0/0xd10 fs/kernfs/file.c:623 do_dentry_open+0x978/0x1460 fs/open.c:958 vfs_open+0x3e/0x330 fs/open.c:1088 do_open fs/namei.c:3774 [inline] path_openat+0x2c84/0x3590 fs/namei.c:3933 do_filp_open+0x235/0x490 fs/namei.c:3960 do_sys_openat2+0x13e/0x1d0 fs/open.c:1415 do_sys_open fs/open.c:1430 [inline] __do_sys_openat fs/open.c:1446 [inline] __se_sys_openat fs/open.c:1441 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1441 page last free pid 35 tgid 35 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0xdf9/0x1140 mm/page_alloc.c:2657 stack_depot_save_flags+0x6f6/0x830 lib/stackdepot.c:666 kasan_save_stack mm/kasan/common.c:48 [inline] kasan_save_track+0x51/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:257 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_node_noprof+0x22a/0x440 mm/slub.c:4270 kmalloc_array_node_noprof include/linux/slab.h:995 [inline] alloc_slab_obj_exts mm/slub.c:1968 [inline] account_slab mm/slub.c:2541 [inline] allocate_slab+0xb6/0x2f0 mm/slub.c:2596 new_slab mm/slub.c:2631 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3818 __slab_alloc+0x58/0xa0 mm/slub.c:3908 __slab_alloc_node mm/slub.c:3961 [inline] slab_alloc_node mm/slub.c:4122 [inline] kmem_cache_alloc_lru_noprof+0x1c5/0x2b0 mm/slub.c:4153 alloc_inode+0x87/0x1a0 fs/inode.c:267 new_inode_pseudo fs/inode.c:1104 [inline] new_inode+0x22/0x1d0 fs/inode.c:1123 debugfs_get_inode fs/debugfs/inode.c:72 [inline] __debugfs_create_file+0x142/0x4b0 fs/debugfs/inode.c:433 nsim_ethtool_init+0x2af/0x460 drivers/net/netdevsim/ethtool.c:207 nsim_create+0x1f6/0x890 drivers/net/netdevsim/netdev.c:748 __nsim_dev_port_add+0x6c0/0xae0 drivers/net/netdevsim/dev.c:1393 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1449 [inline] nsim_dev_reload_create drivers/net/netdevsim/dev.c:1501 [inline] nsim_dev_reload_up+0x69b/0x8e0 drivers/net/netdevsim/dev.c:988 Memory state around the buggy address: ffff888076e54800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076e54880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888076e54900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888076e54980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076e54a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================