From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f78.google.com (mail-ot1-f78.google.com [209.85.210.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E65512E6CC7 for ; Sat, 6 Jun 2026 16:43:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780764217; cv=none; b=lSZ2ghaDaJu1I9clM5qTe8mYR6QKWe0h4COTORZXb+94pk/MlUQlMlOrNCVjEmVsgY8gEJptsMMV9iKD2AAX212Rhy9h79HwbqSInnDZ2nDAWgbe15i1qq/SXZ0Ef8v5Y7CSWr7nEukUZtlOy6RtucokS/kc/sldTDK9Bmj+a+Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780764217; c=relaxed/simple; bh=N1cMyWdy2eTSuBOraWn76SHNvwH/nqNjhmSv5ad8U48=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=N6HzKlQBC2Xd722Oipgu2Uru6Qv80Eon0gsmV/OPreamlX5gqA5rX2BOp4q63+xYJawG2ZYY81g6dZ7JwCPRz+KDIgUevgYgCnQy2Wf3wQO5jC0jfcvGom88fzXAkP3KkLaZZa28ONGietyeeTvypambOwgxcErVxpNpV5+Q/mk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.210.78 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-ot1-f78.google.com with SMTP id 46e09a7af769-7e6db540d17so5747845a34.0 for ; Sat, 06 Jun 2026 09:43:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780764214; x=1781369014; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=mdCPkvJAxBED08vCYu3LyBpnUNR81kJq+FrazPIoX6c=; b=ShTuhx5F+UcjyKQ2JqWhHAfRmN+hWOaMXmU6+1VZUbZclIwkmU4drB0i9GtE53ZvkW C2o29l8fzWsrtPHhKxQKqpuvtML5VJAHsDmql+Erf/jV8DcjkbeLBhLSk6Vt4G+8nf1h YK28F/esH050pGpHgEUfnxRlYmWMm5vecfL85eM9XpvjDOnFK7ImLSptJXnazFXYOfMj MB7mVHe2++3rqqU4uobfWX1oXBHpq30t7rCyaRCTsDgtN+eouqCpVjwnBGyFH+HhyNc5 9W7X/SPK9qlH+0GHPakYQjhJeiBymYp35A4yksv/VtNBxRhv+ovdizdIpryZBVSifUaQ xL2w== X-Forwarded-Encrypted: i=1; AFNElJ8/GQlcoJmBfC0MZcXwP2TX0A326ovJOaRkn70K/Pf5Y49TrBYx1L2j9OSszwt0R4Fa5W03i6840jvx7FI=@vger.kernel.org X-Gm-Message-State: AOJu0Yyu/UNX49c1gHuK3iT5vjDPnjFbuh/nJ8eO+P3df7VED1o9vOIJ aMlHrF5Fc+a8aoQ9s6eDJuh73mw+HNIbiHiC2ZC+zNLJbJTSSulZ5KCMNUqG1MuB2QAmJqZCGfB jujlhwiVCYZqndsvynzSToQtZGMz4idWHXD7h4rHyg6/XUeSmx2mh9qNCgv8= Precedence: bulk X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:161f:b0:69e:6e2a:d63d with SMTP id 006d021491bc7-69e6e2adda4mr3371193eaf.31.1780764214714; Sat, 06 Jun 2026 09:43:34 -0700 (PDT) Date: Sat, 06 Jun 2026 09:43:34 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a244e36.c25708ab.1b19ef.0007.GAE@google.com> Subject: [syzbot] [crypto?] KMSAN: uninit-value in sw842_compress (2) From: syzbot To: davem@davemloft.net, haren@us.ibm.com, herbert@gondor.apana.org.au, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 6f3ed7fec72f Merge tag 'for-7.1/dm-fixes-3' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17311750580000 kernel config: https://syzkaller.appspot.com/x/.config?x=a0ca3b8cb3875012 dashboard link: https://syzkaller.appspot.com/bug?extid=bf5586280a66e9ccdfa9 compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/74be992d336f/disk-6f3ed7fe.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d51c3e8d59b5/vmlinux-6f3ed7fe.xz kernel image: https://storage.googleapis.com/syzbot-assets/34df0814d707/bzImage-6f3ed7fe.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+bf5586280a66e9ccdfa9@syzkaller.appspotmail.com ===================================================== 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:280 crypto_acomp_compress+0x5c4/0xe50 crypto/acompress.c:287 zswap_compress mm/zswap.c:874 [inline] zswap_store_page mm/zswap.c:1415 [inline] zswap_store+0x1a1d/0x48b0 mm/zswap.c:1526 swap_writeout+0x7a1/0x1120 mm/page_io.c:275 shmem_writeout+0x1db1/0x2210 mm/shmem.c:1705 writeout mm/vmscan.c:630 [inline] pageout mm/vmscan.c:679 [inline] shrink_folio_list+0x5ade/0x8000 mm/vmscan.c:1400 evict_folios+0x9704/0xbb70 mm/vmscan.c:4854 try_to_shrink_lruvec+0x1734/0x24b0 mm/vmscan.c:5009 lru_gen_shrink_lruvec mm/vmscan.c:5173 [inline] shrink_lruvec+0x4f8/0x4e20 mm/vmscan.c:5932 shrink_node_memcgs mm/vmscan.c:6171 [inline] shrink_node+0xf19/0x5a30 mm/vmscan.c:6215 shrink_zones mm/vmscan.c:6454 [inline] do_try_to_free_pages+0x956/0x2640 mm/vmscan.c:6516 try_to_free_mem_cgroup_pages+0x352/0x920 mm/vmscan.c:6838 try_charge_memcg+0x815/0x1c20 mm/memcontrol.c:2627 charge_memcg+0x113/0x410 mm/memcontrol.c:5021 __mem_cgroup_charge+0x71/0x2e0 mm/memcontrol.c:5038 mem_cgroup_charge include/linux/memcontrol.h:644 [inline] shmem_alloc_and_add_folio+0xe4d/0x1bd0 mm/shmem.c:1985 shmem_get_folio_gfp+0xad3/0x1fc0 mm/shmem.c:2564 shmem_get_folio mm/shmem.c:2670 [inline] shmem_write_begin+0x230/0x560 mm/shmem.c:3303 generic_perform_write+0x364/0x1050 mm/filemap.c:4325 shmem_file_write_iter+0x2b7/0x2f0 mm/shmem.c:3478 __kernel_write_iter+0x6f9/0xdd0 fs/read_write.c:621 dump_emit_page fs/coredump.c:1304 [inline] dump_user_range+0x1936/0x2070 fs/coredump.c:1378 elf_core_dump+0x697e/0x6c30 fs/binfmt_elf.c:2109 coredump_write+0x20c9/0x2ce0 fs/coredump.c:1053 do_coredump fs/coredump.c:1132 [inline] vfs_coredump+0x7ae1/0x8f00 fs/coredump.c:1206 get_signal+0x2075/0x29f0 kernel/signal.c:3022 arch_do_signal_or_restart+0x53/0xc70 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop kernel/entry/common.c:98 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline] irqentry_exit+0x16f/0xa00 kernel/entry/common.c:162 exc_page_fault+0x7e/0xb0 arch/x86/mm/fault.c:1530 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:618 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+0xe91/0x3810 lib/iov_iter.c:491 generic_perform_write+0x8b7/0x1050 mm/filemap.c:4343 shmem_file_write_iter+0x2b7/0x2f0 mm/shmem.c:3478 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:1925 [inline] loop_process_work+0xf05/0x1ff0 drivers/block/loop.c:1960 loop_workfn+0x3e/0x60 drivers/block/loop.c:1984 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb65/0x1e40 kernel/workqueue.c:3397 worker_thread+0xee4/0x1590 kernel/workqueue.c:3478 kthread+0x53a/0x5f0 kernel/kthread.c:436 ret_from_fork+0x20f/0x8d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Uninit was created at: __alloc_frozen_pages_noprof+0x6fa/0x1000 mm/page_alloc.c:5244 __alloc_pages_noprof mm/page_alloc.c:5255 [inline] alloc_pages_bulk_noprof+0x1664/0x1aa0 mm/page_alloc.c:5175 btrfs_alloc_page_array fs/btrfs/extent_io.c:675 [inline] alloc_eb_folio_array fs/btrfs/extent_io.c:699 [inline] alloc_extent_buffer+0xa85/0x4670 fs/btrfs/extent_io.c:3495 btrfs_find_create_tree_block+0x44/0x60 fs/btrfs/disk-io.c:574 btrfs_init_new_buffer fs/btrfs/extent-tree.c:5260 [inline] btrfs_alloc_tree_block+0x3fe/0x1bc0 fs/btrfs/extent-tree.c:5373 btrfs_alloc_log_tree_node fs/btrfs/disk-io.c:890 [inline] btrfs_add_log_tree+0x243/0x7a0 fs/btrfs/disk-io.c:938 start_log_trans fs/btrfs/tree-log.c:349 [inline] btrfs_log_inode_parent+0x9cf/0x1e00 fs/btrfs/tree-log.c:7562 btrfs_log_dentry_safe+0x96/0x130 fs/btrfs/tree-log.c:7668 btrfs_sync_file+0x16bc/0x21c0 fs/btrfs/file.c:1736 vfs_fsync_range+0x135/0x1c0 fs/sync.c:186 generic_write_sync include/linux/fs.h:2654 [inline] btrfs_do_write_iter+0xb20/0xd70 fs/btrfs/file.c:1473 btrfs_file_write_iter+0x38/0x50 fs/btrfs/file.c:1483 do_iter_readv_writev+0x9e0/0xc10 fs/read_write.c:-1 vfs_writev+0x52a/0x1500 fs/read_write.c:1059 do_pwritev fs/read_write.c:1155 [inline] __do_sys_pwritev2 fs/read_write.c:1213 [inline] __se_sys_pwritev2+0x22f/0x470 fs/read_write.c:1204 __x64_sys_pwritev2+0xe4/0x150 fs/read_write.c:1204 x64_sys_call+0x10a2/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:329 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15d/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 0 UID: 0 PID: 15366 Comm: syz.6.2383 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 ===================================================== --- 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