syzbot

F2FS-fs (loop8): build fault injection rate: 690
F2FS-fs (loop8): invalid crc value
F2FS-fs (loop8): f2fs_recover_fsync_data: recovery fsync data, check_only: 0
F2FS-fs (loop8): Mounted with checkpoint version = 48b305e5
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BUG: KMSAN: uninit-value in sw842_compress+0xd09/0x5060 lib/842/842_compress.c:528
 sw842_compress+0xd09/0x5060 lib/842/842_compress.c:528
 crypto842_scompress+0x4e/0x70 crypto/842.c:46
 scomp_acomp_comp_decomp+0xa49/0x1120 include/crypto/internal/scompress.h:-1
 scomp_acomp_compress+0x33/0x40 crypto/scompress.c:282
 crypto_acomp_compress+0x5b4/0xe80 crypto/acompress.c:291
 zswap_compress mm/zswap.c:886 [inline]
 zswap_store_page mm/zswap.c:1428 [inline]
 zswap_store+0x1a23/0x4b20 mm/zswap.c:1539
 swap_writeout+0x8bd/0x1380 mm/page_io.c:275
 shmem_writeout+0x1ac0/0x1f50 mm/shmem.c:1690
 writeout mm/vmscan.c:649 [inline]
 pageout mm/vmscan.c:698 [inline]
 shrink_folio_list+0x5951/0x7fd0 mm/vmscan.c:1418
 evict_folios+0x9aa3/0xc030 mm/vmscan.c:4711
 try_to_shrink_lruvec+0x1251/0x1750 mm/vmscan.c:4874
 lru_gen_shrink_lruvec mm/vmscan.c:5023 [inline]
 shrink_lruvec+0x505/0x4d80 mm/vmscan.c:5784
 shrink_node_memcgs mm/vmscan.c:6020 [inline]
 shrink_node+0xf09/0x51a0 mm/vmscan.c:6061
 shrink_zones mm/vmscan.c:6300 [inline]
 do_try_to_free_pages+0x956/0x26c0 mm/vmscan.c:6362
 try_to_free_mem_cgroup_pages+0x3ad/0x950 mm/vmscan.c:6690
 try_charge_memcg+0x80b/0x1c20 mm/memcontrol.c:2388
 obj_cgroup_charge_pages+0x69/0x330 mm/memcontrol.c:2823
 __memcg_kmem_charge_page+0x149/0x4c0 mm/memcontrol.c:2867
 __alloc_frozen_pages_noprof+0x680/0xf50 mm/page_alloc.c:5257
 alloc_pages_mpol+0x328/0x860 mm/mempolicy.c:2486
 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline]
 alloc_pages_noprof+0x101/0x280 mm/mempolicy.c:2577
 vm_area_alloc_pages mm/vmalloc.c:3718 [inline]
 __vmalloc_area_node mm/vmalloc.c:3863 [inline]
 __vmalloc_node_range_noprof+0x1579/0x2d80 mm/vmalloc.c:4051
 __vmalloc_node_noprof mm/vmalloc.c:4111 [inline]
 __vmalloc_noprof+0x128/0x1f0 mm/vmalloc.c:4127
 do_replace+0x451/0x8b0 net/bridge/netfilter/ebtables.c:1135
 do_ebt_set_ctl+0x24d/0x2230 net/bridge/netfilter/ebtables.c:2527
 nf_setsockopt+0x4fb/0x550 net/netfilter/nf_sockopt.c:101
 ip_setsockopt+0x1f2/0x210 net/ipv4/ip_sockglue.c:1424
 sock_common_setsockopt+0xf5/0x140 net/core/sock.c:3973
 do_sock_setsockopt net/socket.c:2322 [inline]
 __sys_setsockopt+0x43e/0x580 net/socket.c:2347
 __do_sys_setsockopt net/socket.c:2353 [inline]
 __se_sys_setsockopt net/socket.c:2350 [inline]
 __x64_sys_setsockopt+0xf4/0x1a0 net/socket.c:2350
 x64_sys_call+0x28e3/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:55
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 memcpy_from_iter lib/iov_iter.c:85 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:306 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 __copy_from_iter lib/iov_iter.c:261 [inline]
 copy_folio_from_iter_atomic+0xea0/0x38b0 lib/iov_iter.c:491
 generic_perform_write+0x8b7/0x1050 mm/filemap.c:4332
 shmem_file_write_iter+0x2b7/0x2f0 mm/shmem.c:3518
 lo_rw_aio+0x1164/0x14a0 drivers/block/loop.c:-1
 do_req_filebacked drivers/block/loop.c:-1 [inline]
 loop_handle_cmd drivers/block/loop.c:1926 [inline]
 loop_process_work+0xf05/0x1ff0 drivers/block/loop.c:1961
 loop_workfn+0x3e/0x60 drivers/block/loop.c:1985
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xae7/0x1d60 kernel/workqueue.c:3340
 worker_thread+0x1741/0x1de0 kernel/workqueue.c:3421
 kthread+0xd5a/0xf00 kernel/kthread.c:463
 ret_from_fork+0x207/0x6f0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Uninit was created at:
 __alloc_frozen_pages_noprof+0x6df/0xf50 mm/page_alloc.c:5263
 __alloc_pages_noprof mm/page_alloc.c:5274 [inline]
 alloc_pages_bulk_noprof+0x11f6/0x19d0 mm/page_alloc.c:5194
 btrfs_alloc_page_array fs/btrfs/extent_io.c:677 [inline]
 alloc_eb_folio_array+0x15a/0x670 fs/btrfs/extent_io.c:701
 alloc_extent_buffer+0x884/0x3cf0 fs/btrfs/extent_io.c:3433
 btrfs_find_create_tree_block+0x44/0x60 fs/btrfs/disk-io.c:592
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:5049 [inline]
 btrfs_alloc_tree_block+0x3fe/0x1bc0 fs/btrfs/extent-tree.c:5162
 btrfs_alloc_log_tree_node fs/btrfs/disk-io.c:912 [inline]
 btrfs_add_log_tree+0x243/0x7a0 fs/btrfs/disk-io.c:960
 start_log_trans fs/btrfs/tree-log.c:349 [inline]
 btrfs_log_inode_parent+0x9cf/0x1e00 fs/btrfs/tree-log.c:7508
 btrfs_log_dentry_safe+0x96/0x130 fs/btrfs/tree-log.c:7614
 btrfs_sync_file+0x1990/0x22e0 fs/btrfs/file.c:1733
 vfs_fsync_range+0x1a1/0x250 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2618 [inline]
 btrfs_do_write_iter+0xb53/0xd90 fs/btrfs/file.c:1470
 btrfs_file_write_iter+0x38/0x50 fs/btrfs/file.c:1480
 iter_file_splice_write+0x12f1/0x20f0 fs/splice.c:738
 do_splice_from fs/splice.c:938 [inline]
 direct_splice_actor+0x31a/0x7d0 fs/splice.c:1161
 splice_direct_to_actor+0x9a3/0x1560 fs/splice.c:1105
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0x1e0/0x350 fs/splice.c:1230
 do_sendfile+0x9fc/0x1130 fs/read_write.c:1370
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64+0x1ea/0x290 fs/read_write.c:1417
 __x64_sys_sendfile64+0xbd/0x120 fs/read_write.c:1417
 x64_sys_call+0x3a6f/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 21555 Comm: syz.8.3182 Tainted: G        W    L      syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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