syzbot


KMSAN: uninit-value in sw842_decompress (2)

Status: upstream: reported on 2025/04/06 12:32
Subsystems: crypto
[Documentation on labels]
Reported-by: syzbot+8f77ff6144a73f0cf71b@syzkaller.appspotmail.com
First crash: 5d15h, last: 5d15h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [crypto?] KMSAN: uninit-value in sw842_decompress (2) 0 (1) 2025/04/06 12:32
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in sw842_decompress crypto 1 137d 133d 0/28 auto-obsoleted due to no activity on 2025/03/01 12:04

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in crc32_be_base+0x255/0x2b0 lib/crc32.c:131
 crc32_be_base+0x255/0x2b0 lib/crc32.c:131
 crc32_be_arch+0x3d/0x50 arch/x86/lib/crc32-glue.c:77
 crc32_be include/linux/crc32.h:28 [inline]
 sw842_decompress+0x167d/0x1840 lib/842/842_decompress.c:385
 crypto842_sdecompress+0x45/0x60 crypto/842.c:57
 scomp_acomp_comp_decomp+0xa8d/0xd90 crypto/scompress.c:-1
 scomp_acomp_chain crypto/scompress.c:297 [inline]
 scomp_acomp_decompress+0x39/0x1e0 crypto/scompress.c:313
 acomp_do_req_chain+0x39a/0x9f0 crypto/acompress.c:353
 crypto_acomp_decompress+0x5f/0x80 crypto/acompress.c:378
 zswap_decompress+0x561/0xe00 mm/zswap.c:1018
 zswap_load+0x296/0x660 mm/zswap.c:1678
 swap_read_folio+0x691/0x3290 mm/page_io.c:643
 swap_cluster_readahead+0xb48/0xbd0 mm/swap_state.c:638
 swapin_readahead+0x205/0x1690 mm/swap_state.c:814
 do_swap_page+0x982/0x9c50 mm/memory.c:4532
 handle_pte_fault mm/memory.c:6000 [inline]
 __handle_mm_fault mm/memory.c:6140 [inline]
 handle_mm_fault+0x3ea4/0xe360 mm/memory.c:6309
 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline]
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x41e/0x750 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:623

Uninit was created at:
 __alloc_frozen_pages_noprof+0x6a0/0xe30 mm/page_alloc.c:4957
 alloc_pages_mpol+0x4cd/0x890 mm/mempolicy.c:2301
 folio_alloc_mpol_noprof+0x57/0x1c0 mm/mempolicy.c:2320
 __read_swap_cache_async+0x2b6/0x980 mm/swap_state.c:403
 swap_cluster_readahead+0xa94/0xbd0 mm/swap_state.c:635
 swapin_readahead+0x205/0x1690 mm/swap_state.c:814
 do_swap_page+0x982/0x9c50 mm/memory.c:4532
 handle_pte_fault mm/memory.c:6000 [inline]
 __handle_mm_fault mm/memory.c:6140 [inline]
 handle_mm_fault+0x3ea4/0xe360 mm/memory.c:6309
 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline]
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x41e/0x750 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:623

CPU: 0 UID: 0 PID: 25609 Comm: dhcpcd Not tainted 6.14.0-syzkaller-12456-gacc4d5ff0b61 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
=====================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/02 12:25 upstream acc4d5ff0b61 c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sw842_decompress
* Struck through repros no longer work on HEAD.