=====================================================
BUG: KMSAN: use-after-free in sw842_decompress+0x11c8/0x1750 lib/842/842_decompress.c:303
 sw842_decompress+0x11c8/0x1750 lib/842/842_decompress.c:303
 crypto842_sdecompress+0x46/0x60 crypto/842.c:53
 scomp_acomp_comp_decomp+0xa49/0x1120 include/crypto/internal/scompress.h:-1
 scomp_acomp_decompress+0x30/0x40 crypto/scompress.c:285
 crypto_acomp_decompress+0x5b4/0xe80 crypto/acompress.c:301
 zswap_decompress+0x4e7/0xe30 mm/zswap.c:953
 zswap_load+0x262/0x570 mm/zswap.c:1615
 swap_read_folio+0x662/0x3050 mm/page_io.c:637
 swap_cluster_readahead+0xa79/0xb20 mm/swap_state.c:771
 swapin_readahead+0x220/0x19d0 mm/swap_state.c:924
 do_swap_page+0x6ef/0x9b50 mm/memory.c:4801
 handle_pte_fault mm/memory.c:6319 [inline]
 __handle_mm_fault mm/memory.c:6454 [inline]
 handle_mm_fault+0x3036/0x6fc0 mm/memory.c:6623
 do_user_addr_fault+0x1760/0x2510 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x70/0xb0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:618

Uninit was stored to memory at:
 sw842_decompress+0x11c1/0x1750 lib/842/842_decompress.c:303
 crypto842_sdecompress+0x46/0x60 crypto/842.c:53
 scomp_acomp_comp_decomp+0xa49/0x1120 include/crypto/internal/scompress.h:-1
 scomp_acomp_decompress+0x30/0x40 crypto/scompress.c:285
 crypto_acomp_decompress+0x5b4/0xe80 crypto/acompress.c:301
 zswap_decompress+0x4e7/0xe30 mm/zswap.c:953
 zswap_load+0x262/0x570 mm/zswap.c:1615
 swap_read_folio+0x662/0x3050 mm/page_io.c:637
 swap_cluster_readahead+0xa79/0xb20 mm/swap_state.c:771
 swapin_readahead+0x220/0x19d0 mm/swap_state.c:924
 do_swap_page+0x6ef/0x9b50 mm/memory.c:4801
 handle_pte_fault mm/memory.c:6319 [inline]
 __handle_mm_fault mm/memory.c:6454 [inline]
 handle_mm_fault+0x3036/0x6fc0 mm/memory.c:6623
 do_user_addr_fault+0x1760/0x2510 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x70/0xb0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:618

Uninit was stored to memory at:
 next_bits+0xac2/0xda0 lib/842/842_decompress.c:118
 sw842_decompress+0x1a6/0x1750 lib/842/842_decompress.c:297
 crypto842_sdecompress+0x46/0x60 crypto/842.c:53
 scomp_acomp_comp_decomp+0xa49/0x1120 include/crypto/internal/scompress.h:-1
 scomp_acomp_decompress+0x30/0x40 crypto/scompress.c:285
 crypto_acomp_decompress+0x5b4/0xe80 crypto/acompress.c:301
 zswap_decompress+0x4e7/0xe30 mm/zswap.c:953
 zswap_load+0x262/0x570 mm/zswap.c:1615
 swap_read_folio+0x662/0x3050 mm/page_io.c:637
 swap_cluster_readahead+0xa79/0xb20 mm/swap_state.c:771
 swapin_readahead+0x220/0x19d0 mm/swap_state.c:924
 do_swap_page+0x6ef/0x9b50 mm/memory.c:4801
 handle_pte_fault mm/memory.c:6319 [inline]
 __handle_mm_fault mm/memory.c:6454 [inline]
 handle_mm_fault+0x3036/0x6fc0 mm/memory.c:6623
 do_user_addr_fault+0x1760/0x2510 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x70/0xb0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:618

Uninit was created at:
 __free_pages_prepare mm/page_alloc.c:1354 [inline]
 free_pages_prepare+0x10c/0xee0 mm/page_alloc.c:1478
 compaction_free+0x133/0x4b0 mm/compaction.c:1862
 migrate_folio_undo_dst mm/migrate.c:1184 [inline]
 migrate_folios_undo mm/migrate.c:1768 [inline]
 migrate_pages_batch+0x8155/0x8900 mm/migrate.c:1989
 migrate_pages_sync mm/migrate.c:2007 [inline]
 migrate_pages+0x3560/0x5440 mm/migrate.c:2116
 compact_zone+0x3f4e/0x7820 mm/compaction.c:2647
 kcompactd_do_work mm/compaction.c:3098 [inline]
 kcompactd+0x102c/0x24c0 mm/compaction.c:3192
 kthread+0x53f/0x600 kernel/kthread.c:467
 ret_from_fork+0x20f/0x910 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

CPU: 1 UID: 101 PID: 5423 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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