=====================================================
BUG: KMSAN: uninit-value in zswap_is_page_same_filled mm/zswap.c:1471 [inline]
BUG: KMSAN: uninit-value in zswap_store+0x1f17/0x3cb0 mm/zswap.c:1568
 zswap_is_page_same_filled mm/zswap.c:1471 [inline]
 zswap_store+0x1f17/0x3cb0 mm/zswap.c:1568
 swap_writepage+0x126/0x4c0 mm/page_io.c:198
 shmem_writepage+0x1824/0x1f70 mm/shmem.c:1518
 pageout mm/vmscan.c:654 [inline]
 shrink_folio_list+0x5617/0x7ad0 mm/vmscan.c:1316
 evict_folios+0xab3a/0xcc50 mm/vmscan.c:4521
 try_to_shrink_lruvec+0x15ac/0x1b20 mm/vmscan.c:4726
 lru_gen_shrink_lruvec mm/vmscan.c:4869 [inline]
 shrink_lruvec+0x483/0x4760 mm/vmscan.c:5647
 shrink_node_memcgs mm/vmscan.c:5867 [inline]
 shrink_node+0xf4d/0x58b0 mm/vmscan.c:5902
 shrink_zones mm/vmscan.c:6141 [inline]
 do_try_to_free_pages+0x8fe/0x2530 mm/vmscan.c:6203
 try_to_free_mem_cgroup_pages+0x3c0/0xa30 mm/vmscan.c:6518
 try_charge_memcg+0x556/0x27a0 mm/memcontrol.c:2782
 obj_cgroup_charge_pages+0x2c2/0x5a0 mm/memcontrol.c:3301
 __memcg_kmem_charge_page+0x14c/0x520 mm/memcontrol.c:3327
 __alloc_pages+0x93c/0xe00 mm/page_alloc.c:4584
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 bpf_ringbuf_area_alloc kernel/bpf/ringbuf.c:122 [inline]
 bpf_ringbuf_alloc+0x126/0x6e0 kernel/bpf/ringbuf.c:170
 ringbuf_map_alloc+0x39a/0x520 kernel/bpf/ringbuf.c:204
 map_create+0xefc/0x1a30 kernel/bpf/syscall.c:1237
 __sys_bpf+0xa0f/0xd60 kernel/bpf/syscall.c:5439
 __do_sys_bpf kernel/bpf/syscall.c:5561 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5559 [inline]
 __ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5559
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb5/0x110 arch/x86/entry/common.c:321
 do_fast_syscall_32+0x37/0x70 arch/x86/entry/common.c:346
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:384
 entry_SYSENTER_compat_after_hwframe+0x70/0x7a

Uninit was stored to memory at:
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:122 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:249 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 __copy_from_iter lib/iov_iter.c:268 [inline]
 copy_page_from_iter_atomic+0x12f5/0x2b70 lib/iov_iter.c:500
 generic_perform_write+0x4ae/0xc40 mm/filemap.c:3938
 shmem_file_write_iter+0x2b5/0x2e0 mm/shmem.c:2893
 do_iter_readv_writev+0x655/0x7a0
 vfs_iter_write+0x455/0xd00 fs/read_write.c:895
 lo_write_bvec drivers/block/loop.c:246 [inline]
 lo_write_simple drivers/block/loop.c:267 [inline]
 do_req_filebacked drivers/block/loop.c:491 [inline]
 loop_handle_cmd drivers/block/loop.c:1909 [inline]
 loop_process_work+0x14f9/0x3430 drivers/block/loop.c:1944
 loop_workfn+0x48/0x60 drivers/block/loop.c:1968
 process_one_work kernel/workqueue.c:2633 [inline]
 process_scheduled_works+0x1132/0x1f40 kernel/workqueue.c:2706
 worker_thread+0xea4/0x1560 kernel/workqueue.c:2787
 kthread+0x3ed/0x550 kernel/kthread.c:388
 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

Uninit was created at:
 __alloc_pages+0x9a6/0xe00 mm/page_alloc.c:4590
 alloc_pages_mpol+0x62b/0x9d0 mm/mempolicy.c:2133
 alloc_pages mm/mempolicy.c:2204 [inline]
 folio_alloc+0x1da/0x380 mm/mempolicy.c:2211
 filemap_alloc_folio+0xa5/0x430 mm/filemap.c:975
 __filemap_get_folio+0x9aa/0x13f0 mm/filemap.c:1919
 ext4_write_begin+0x3e5/0x2230 fs/ext4/inode.c:1159
 ext4_da_write_begin+0x4cd/0xec0 fs/ext4/inode.c:2869
 generic_perform_write+0x3f5/0xc40 mm/filemap.c:3930
 ext4_buffered_write_iter+0x564/0xaa0 fs/ext4/file.c:299
 ext4_file_write_iter+0x20f/0x3470
 __kernel_write_iter+0x686/0xc30 fs/read_write.c:523
 dump_emit_page fs/coredump.c:888 [inline]
 dump_user_range+0x593/0xcd0 fs/coredump.c:915
 elf_core_dump+0x59ee/0x5c60 fs/binfmt_elf.c:2077
 do_coredump+0x32c9/0x4920 fs/coredump.c:764
 get_signal+0x21fa/0x2d80 kernel/signal.c:2879
 arch_do_signal_or_restart+0x53/0xca0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:105 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline]
 syscall_exit_to_user_mode+0x5c/0x170 kernel/entry/common.c:212
 __do_fast_syscall_32+0xc5/0x110 arch/x86/entry/common.c:324
 do_fast_syscall_32+0x37/0x70 arch/x86/entry/common.c:346
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:384
 entry_SYSENTER_compat_after_hwframe+0x70/0x7a

CPU: 0 PID: 15045 Comm: syz-executor.3 Not tainted 6.8.0-rc4-syzkaller-00180-g4f5e5092fdbf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
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