syzbot

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BUG: KMSAN: uninit-value in LZ4_decompress_generic lib/lz4/lz4_decompress.c:147 [inline]
BUG: KMSAN: uninit-value in LZ4_decompress_safe_partial+0x94a/0x2190 lib/lz4/lz4_decompress.c:472
 LZ4_decompress_generic lib/lz4/lz4_decompress.c:147 [inline]
 LZ4_decompress_safe_partial+0x94a/0x2190 lib/lz4/lz4_decompress.c:472
 __bio_uncompress+0x627/0x1490 fs/bcachefs/compress.c:200
 bch2_bio_uncompress+0x507/0x9b0 fs/bcachefs/compress.c:323
 __bch2_read_endio+0x17e4/0x2240 fs/bcachefs/io_read.c:871
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3319
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3400
 kthread+0xd5c/0xf00 kernel/kthread.c:463
 ret_from_fork+0x233/0x380 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Uninit was created at:
 __alloc_frozen_pages_noprof+0x689/0xf00 mm/page_alloc.c:5171
 alloc_pages_mpol+0x328/0x860 mm/mempolicy.c:2416
 alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline]
 alloc_pages_noprof+0x102/0x280 mm/mempolicy.c:2507
 __bio_alloc_page_pool fs/bcachefs/io_write.c:121 [inline]
 bch2_bio_alloc_pages_pool+0x8f/0x230 fs/bcachefs/io_write.c:142
 __bch2_read_extent+0x334e/0x6220 fs/bcachefs/io_read.c:1193
 bch2_read_extent fs/bcachefs/io_read.h:147 [inline]
 bchfs_read+0x3ccb/0x4800 fs/bcachefs/fs-io-buffered.c:226
 bch2_readahead+0x1579/0x1c10 fs/bcachefs/fs-io-buffered.c:316
 read_pages+0x15c/0xe30 mm/readahead.c:160
 page_cache_ra_order+0xdc7/0x13f0 mm/readahead.c:512
 page_cache_sync_ra+0x10ac/0x1410 mm/readahead.c:619
 filemap_get_pages+0xfb3/0x3a60 mm/filemap.c:2603
 filemap_read+0x5d2/0x2300 mm/filemap.c:2712
 bch2_read_iter+0x559/0x21b0 fs/bcachefs/fs-io-direct.c:222
 __kernel_read+0x7e1/0xe20 fs/read_write.c:530
 integrity_kernel_read+0x77/0x90 security/integrity/iint.c:28
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:480 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:511 [inline]
 ima_calc_file_hash+0x17cb/0x4050 security/integrity/ima/ima_crypto.c:568
 ima_collect_measurement+0x45d/0xe50 security/integrity/ima/ima_api.c:293
 process_measurement+0x2d1a/0x40e0 security/integrity/ima/ima_main.c:405
 ima_file_check+0x8e/0xd0 security/integrity/ima/ima_main.c:633
 security_file_post_open+0xbf/0x530 security/security.c:3160
 do_open fs/namei.c:3889 [inline]
 path_openat+0x5ac3/0x6760 fs/namei.c:4046
 do_filp_open+0x280/0x660 fs/namei.c:4073
 do_sys_openat2+0x1bb/0x2f0 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_openat fs/open.c:1466 [inline]
 __se_sys_openat fs/open.c:1461 [inline]
 __x64_sys_openat+0x240/0x300 fs/open.c:1461
 x64_sys_call+0x3bcc/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 3761 Comm: kworker/u8:14 Tainted: G        W           syzkaller #0 PREEMPT(none) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events_unbound __bch2_read_endio
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