===================================================== BUG: KMSAN: uninit-value in sw842_decompress+0x11f3/0x1780 lib/842/842_decompress.c:303 sw842_decompress+0x11f3/0x1780 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:287 crypto_acomp_decompress+0x5b4/0xe80 crypto/acompress.c:303 zswap_decompress+0x729/0x1000 mm/zswap.c:967 zswap_load+0x262/0x570 mm/zswap.c:1627 swap_read_folio+0x662/0x3050 mm/page_io.c:637 swap_cluster_readahead+0xa8c/0xb20 mm/swap_state.c:668 swapin_readahead+0x217/0x1990 mm/swap_state.c:821 do_swap_page+0x984/0x99b0 mm/memory.c:4753 handle_pte_fault mm/memory.c:6276 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x3034/0x6ee0 mm/memory.c:6580 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x2f05/0x5f50 mm/gup.c:1428 __get_user_pages_locked mm/gup.c:1692 [inline] get_dump_page+0x143/0x590 mm/gup.c:2192 dump_user_range+0x25d/0x14c0 fs/coredump.c:1366 elf_core_dump+0x6a96/0x6da0 fs/binfmt_elf.c:2111 coredump_write+0x20b6/0x2d60 fs/coredump.c:1049 do_coredump fs/coredump.c:1126 [inline] vfs_coredump+0x79b7/0x8cf0 fs/coredump.c:1200 get_signal+0x20a9/0x2a20 kernel/signal.c:3019 arch_do_signal_or_restart+0x53/0xc00 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop kernel/entry/common.c:75 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline] irqentry_exit+0xf2/0x720 kernel/entry/common.c:196 exc_page_fault+0x82/0xc0 arch/x86/mm/fault.c:1535 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:618 Uninit was stored to memory at: sw842_decompress+0x11ec/0x1780 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:287 crypto_acomp_decompress+0x5b4/0xe80 crypto/acompress.c:303 zswap_decompress+0x729/0x1000 mm/zswap.c:967 zswap_load+0x262/0x570 mm/zswap.c:1627 swap_read_folio+0x662/0x3050 mm/page_io.c:637 swap_cluster_readahead+0xa8c/0xb20 mm/swap_state.c:668 swapin_readahead+0x217/0x1990 mm/swap_state.c:821 do_swap_page+0x984/0x99b0 mm/memory.c:4753 handle_pte_fault mm/memory.c:6276 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x3034/0x6ee0 mm/memory.c:6580 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x2f05/0x5f50 mm/gup.c:1428 __get_user_pages_locked mm/gup.c:1692 [inline] get_dump_page+0x143/0x590 mm/gup.c:2192 dump_user_range+0x25d/0x14c0 fs/coredump.c:1366 elf_core_dump+0x6a96/0x6da0 fs/binfmt_elf.c:2111 coredump_write+0x20b6/0x2d60 fs/coredump.c:1049 do_coredump fs/coredump.c:1126 [inline] vfs_coredump+0x79b7/0x8cf0 fs/coredump.c:1200 get_signal+0x20a9/0x2a20 kernel/signal.c:3019 arch_do_signal_or_restart+0x53/0xc00 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop kernel/entry/common.c:75 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline] irqentry_exit+0xf2/0x720 kernel/entry/common.c:196 exc_page_fault+0x82/0xc0 arch/x86/mm/fault.c:1535 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+0x1a6/0x1780 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:287 crypto_acomp_decompress+0x5b4/0xe80 crypto/acompress.c:303 zswap_decompress+0x729/0x1000 mm/zswap.c:967 zswap_load+0x262/0x570 mm/zswap.c:1627 swap_read_folio+0x662/0x3050 mm/page_io.c:637 swap_cluster_readahead+0xa8c/0xb20 mm/swap_state.c:668 swapin_readahead+0x217/0x1990 mm/swap_state.c:821 do_swap_page+0x984/0x99b0 mm/memory.c:4753 handle_pte_fault mm/memory.c:6276 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x3034/0x6ee0 mm/memory.c:6580 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x2f05/0x5f50 mm/gup.c:1428 __get_user_pages_locked mm/gup.c:1692 [inline] get_dump_page+0x143/0x590 mm/gup.c:2192 dump_user_range+0x25d/0x14c0 fs/coredump.c:1366 elf_core_dump+0x6a96/0x6da0 fs/binfmt_elf.c:2111 coredump_write+0x20b6/0x2d60 fs/coredump.c:1049 do_coredump fs/coredump.c:1126 [inline] vfs_coredump+0x79b7/0x8cf0 fs/coredump.c:1200 get_signal+0x20a9/0x2a20 kernel/signal.c:3019 arch_do_signal_or_restart+0x53/0xc00 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop kernel/entry/common.c:75 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline] irqentry_exit+0xf2/0x720 kernel/entry/common.c:196 exc_page_fault+0x82/0xc0 arch/x86/mm/fault.c:1535 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:618 Uninit was created at: __alloc_frozen_pages_noprof+0x421/0xab0 mm/page_alloc.c:5233 __alloc_pages_noprof+0x41/0xd0 mm/page_alloc.c:5244 __alloc_pages_node_noprof include/linux/gfp.h:285 [inline] alloc_pages_node_noprof include/linux/gfp.h:312 [inline] alloc_zpdesc mm/zsmalloc.c:237 [inline] alloc_zspage+0x394/0x19f0 mm/zsmalloc.c:984 zs_malloc+0x79d/0x1250 mm/zsmalloc.c:1300 zswap_compress mm/zswap.c:909 [inline] zswap_store_page mm/zswap.c:1428 [inline] zswap_store+0x24a0/0x4a90 mm/zswap.c:1539 swap_writeout+0x8c1/0x1390 mm/page_io.c:275 writeout mm/vmscan.c:651 [inline] pageout mm/vmscan.c:698 [inline] shrink_folio_list+0x59e0/0x7fc0 mm/vmscan.c:1418 evict_folios+0x999d/0xbf30 mm/vmscan.c:4711 try_to_shrink_lruvec+0x12b6/0x17e0 mm/vmscan.c:4874 shrink_one+0x43c/0xbd0 mm/vmscan.c:4919 shrink_many mm/vmscan.c:4982 [inline] lru_gen_shrink_node mm/vmscan.c:5060 [inline] shrink_node+0x453a/0x51e0 mm/vmscan.c:6047 shrink_zones mm/vmscan.c:6300 [inline] do_try_to_free_pages+0x849/0x26b0 mm/vmscan.c:6362 try_to_free_pages+0x986/0x16d0 mm/vmscan.c:6608 __perform_reclaim mm/page_alloc.c:4377 [inline] __alloc_pages_direct_reclaim+0x10d/0x340 mm/page_alloc.c:4399 __alloc_pages_slowpath+0xd30/0x18f0 mm/page_alloc.c:4843 __alloc_frozen_pages_noprof+0x595/0xab0 mm/page_alloc.c:5223 alloc_pages_mpol+0x328/0x860 mm/mempolicy.c:2486 folio_alloc_mpol_noprof+0x56/0x1d0 mm/mempolicy.c:2505 shmem_alloc_folio mm/shmem.c:1890 [inline] shmem_alloc_and_add_folio+0xc56/0x1bd0 mm/shmem.c:1932 shmem_get_folio_gfp+0xad3/0x1fc0 mm/shmem.c:2556 shmem_get_folio mm/shmem.c:2662 [inline] shmem_write_begin+0x230/0x570 mm/shmem.c:3315 generic_perform_write+0x365/0x1050 mm/filemap.c:4314 shmem_file_write_iter+0x2b7/0x2f0 mm/shmem.c:3490 new_sync_write fs/read_write.c:593 [inline] vfs_write+0xbe2/0x15d0 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+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 1 UID: 0 PID: 9671 Comm: syz.1.986 Not tainted syzkaller #0 PREEMPT(none) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 =====================================================