=====================================================
BUG: KMSAN: uninit-value in __hfsplus_ext_read_extent fs/hfsplus/extents.c:167 [inline]
BUG: KMSAN: uninit-value in __hfsplus_ext_cache_extent+0x7cb/0x990 fs/hfsplus/extents.c:191
 __hfsplus_ext_read_extent fs/hfsplus/extents.c:167 [inline]
 __hfsplus_ext_cache_extent+0x7cb/0x990 fs/hfsplus/extents.c:191
 hfsplus_ext_read_extent fs/hfsplus/extents.c:218 [inline]
 hfsplus_file_extend+0x7b5/0x1df0 fs/hfsplus/extents.c:462
 hfsplus_get_block+0xfc3/0x1a20 fs/hfsplus/extents.c:245
 __block_write_begin_int+0xa76/0x3030 fs/buffer.c:2151
 block_write_begin fs/buffer.c:2262 [inline]
 cont_write_begin+0x10e1/0x1bc0 fs/buffer.c:2601
 hfsplus_write_begin+0x85/0x130 fs/hfsplus/inode.c:46
 generic_perform_write+0x3f4/0x10c0 mm/filemap.c:4112
 __generic_file_write_iter+0x213/0x460 mm/filemap.c:4229
 generic_file_write_iter+0x131/0x980 mm/filemap.c:4255
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0xb48/0x1580 fs/read_write.c:686
 ksys_write fs/read_write.c:738 [inline]
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746
 x64_sys_call+0x38c3/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 __alloc_frozen_pages_noprof+0x689/0xf00 mm/page_alloc.c:4982
 alloc_pages_mpol+0x328/0x860 mm/mempolicy.c:2419
 alloc_frozen_pages_noprof+0xf7/0x200 mm/mempolicy.c:2490
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab+0x24d/0x1220 mm/slub.c:2619
 new_slab mm/slub.c:2673 [inline]
 ___slab_alloc+0xfec/0x3480 mm/slub.c:3859
 __slab_alloc mm/slub.c:3949 [inline]
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __kmalloc_cache_noprof+0x8ff/0xed0 mm/slub.c:4354
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 ref_tracker_alloc+0x13a/0x7a0 lib/ref_tracker.c:203
 __netdev_tracker_alloc include/linux/netdevice.h:4341 [inline]
 netdev_hold include/linux/netdevice.h:4370 [inline]
 qdisc_alloc+0x6fd/0xc80 net/sched/sch_generic.c:987
 qdisc_create_dflt+0x8f/0x640 net/sched/sch_generic.c:1010
 attach_one_default_qdisc net/sched/sch_generic.c:1176 [inline]
 netdev_for_each_tx_queue include/linux/netdevice.h:2655 [inline]
 attach_default_qdiscs net/sched/sch_generic.c:1194 [inline]
 dev_activate+0x4ce/0x1c10 net/sched/sch_generic.c:1253
 __dev_open+0xbc1/0xc60 net/core/dev.c:1692
 __dev_change_flags+0x3a8/0x9f0 net/core/dev.c:9458
 netif_change_flags+0x8d/0x1e0 net/core/dev.c:9521
 do_setlink+0x15c3/0x7e50 net/core/rtnetlink.c:3141
 rtnl_changelink net/core/rtnetlink.c:3759 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3918 [inline]
 rtnl_newlink+0x2fcc/0x3a90 net/core/rtnetlink.c:4055
 rtnetlink_rcv_msg+0x106f/0x14b0 net/core/rtnetlink.c:6944
 netlink_rcv_skb+0x54a/0x680 net/netlink/af_netlink.c:2552
 rtnetlink_rcv+0x35/0x40 net/core/rtnetlink.c:6971
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0xedf/0x1290 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x10b3/0x1250 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x330/0x3d0 net/socket.c:727
 __sys_sendto+0x593/0x720 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0x130/0x200 net/socket.c:2183
 x64_sys_call+0x3c0b/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 19882 Comm: syz.6.4044 Not tainted 6.16.0-syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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