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* [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry
@ 2024-02-20  6:41 syzbot
  2024-02-20 10:40 ` Roberto Sassu
  2024-03-02 22:01 ` [syzbot] [lsm?] [integrity?] " syzbot
  0 siblings, 2 replies; 12+ messages in thread
From: syzbot @ 2024-02-20  6:41 UTC (permalink / raw)
  To: dmitry.kasatkin, eric.snowberg, jmorris, linux-integrity,
	linux-kernel, linux-security-module, paul, roberto.sassu, serge,
	syzkaller-bugs, zohar

Hello,

syzbot found the following issue on:

HEAD commit:    4f5e5092fdbf Merge tag 'net-6.8-rc5' of git://git.kernel.o..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=135ba81c180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e3dd779fba027968
dashboard link: https://syzkaller.appspot.com/bug?extid=7bc44a489f0ef0670bd5
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/34924e0466d4/disk-4f5e5092.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/29d0b1935c61/vmlinux-4f5e5092.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2e033c3d8679/bzImage-4f5e5092.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in ima_add_template_entry+0x52b/0x870 security/integrity/ima/ima_queue.c:172
 ima_add_template_entry+0x52b/0x870 security/integrity/ima/ima_queue.c:172
 ima_store_template security/integrity/ima/ima_api.c:122 [inline]
 ima_store_measurement+0x371/0x8d0 security/integrity/ima/ima_api.c:376
 process_measurement+0x2c6e/0x3ef0 security/integrity/ima/ima_main.c:367
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3643 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3798
 do_filp_open+0x20d/0x590 fs/namei.c:3825
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

<Zero or more stacks not recorded to save memory>

Uninit was stored to memory at:
 sha256_transform lib/crypto/sha256.c:117 [inline]
 sha256_transform_blocks+0x2dbf/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3643 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3798
 do_filp_open+0x20d/0x590 fs/namei.c:3825
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 sha256_transform lib/crypto/sha256.c:117 [inline]
 sha256_transform_blocks+0x2dbf/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3643 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3798
 do_filp_open+0x20d/0x590 fs/namei.c:3825
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 BLEND_OP lib/crypto/sha256.c:61 [inline]
 sha256_transform lib/crypto/sha256.c:91 [inline]
 sha256_transform_blocks+0xf33/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3643 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3798
 do_filp_open+0x20d/0x590 fs/namei.c:3825
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 BLEND_OP lib/crypto/sha256.c:61 [inline]
 sha256_transform lib/crypto/sha256.c:92 [inline]
 sha256_transform_blocks+0xf7d/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3643 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3798
 do_filp_open+0x20d/0x590 fs/namei.c:3825
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 BLEND_OP lib/crypto/sha256.c:61 [inline]
 sha256_transform lib/crypto/sha256.c:93 [inline]
 sha256_transform_blocks+0xfb5/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3643 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3798
 do_filp_open+0x20d/0x590 fs/namei.c:3825
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 LOAD_OP lib/crypto/sha256.c:56 [inline]
 sha256_transform lib/crypto/sha256.c:82 [inline]
 sha256_transform_blocks+0x2c35/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3643 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3798
 do_filp_open+0x20d/0x590 fs/namei.c:3825
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 memcpy_to_iter lib/iov_iter.c:65 [inline]
 iterate_kvec include/linux/iov_iter.h:85 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:251 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x125a/0x2520 lib/iov_iter.c:186
 copy_page_to_iter+0x419/0x870 lib/iov_iter.c:381
 copy_folio_to_iter include/linux/uio.h:181 [inline]
 filemap_read+0xbf4/0x14d0 mm/filemap.c:2654
 generic_file_read_iter+0x136/0xad0 mm/filemap.c:2784
 __kernel_read+0x724/0xce0 fs/read_write.c:434
 integrity_kernel_read+0x77/0x90 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1743/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3643 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3798
 do_filp_open+0x20d/0x590 fs/namei.c:3825
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 __alloc_pages+0x9a6/0xe00 mm/page_alloc.c:4590
 alloc_pages_mpol+0x62b/0x9d0 mm/mempolicy.c:2133
 alloc_pages mm/mempolicy.c:2204 [inline]
 folio_alloc+0x1da/0x380 mm/mempolicy.c:2211
 filemap_alloc_folio+0xa5/0x430 mm/filemap.c:975
 page_cache_ra_unbounded+0x2cc/0x960 mm/readahead.c:247
 do_page_cache_ra mm/readahead.c:299 [inline]
 page_cache_ra_order+0xe31/0xee0 mm/readahead.c:544
 ondemand_readahead+0x157d/0x1750 mm/readahead.c:666
 page_cache_sync_ra+0x724/0x760 mm/readahead.c:693
 page_cache_sync_readahead include/linux/pagemap.h:1300 [inline]
 filemap_get_pages+0x4c4/0x2bd0 mm/filemap.c:2498
 filemap_read+0x59e/0x14d0 mm/filemap.c:2594
 generic_file_read_iter+0x136/0xad0 mm/filemap.c:2784
 __kernel_read+0x724/0xce0 fs/read_write.c:434
 integrity_kernel_read+0x77/0x90 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1743/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3643 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3798
 do_filp_open+0x20d/0x590 fs/namei.c:3825
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

CPU: 1 PID: 9243 Comm: syz-executor.3 Not tainted 6.8.0-rc4-syzkaller-00180-g4f5e5092fdbf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
=====================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry
  2024-02-20  6:41 [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry syzbot
@ 2024-02-20 10:40 ` Roberto Sassu
  2024-03-03 14:54   ` Tetsuo Handa
  2024-03-02 22:01 ` [syzbot] [lsm?] [integrity?] " syzbot
  1 sibling, 1 reply; 12+ messages in thread
From: Roberto Sassu @ 2024-02-20 10:40 UTC (permalink / raw)
  To: syzbot, dmitry.kasatkin, eric.snowberg, jmorris, linux-integrity,
	linux-kernel, linux-security-module, paul, roberto.sassu, serge,
	syzkaller-bugs, zohar, linux-fsdevel

On Mon, 2024-02-19 at 22:41 -0800, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    4f5e5092fdbf Merge tag 'net-6.8-rc5' of git://git.kernel.o..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=135ba81c180000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=e3dd779fba027968
> dashboard link: https://syzkaller.appspot.com/bug?extid=7bc44a489f0ef0670bd5
> compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> 
> Unfortunately, I don't have any reproducer for this issue yet.
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/34924e0466d4/disk-4f5e5092.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/29d0b1935c61/vmlinux-4f5e5092.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/2e033c3d8679/bzImage-4f5e5092.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com
> 
> =====================================================
> BUG: KMSAN: uninit-value in ima_add_template_entry+0x52b/0x870 security/integrity/ima/ima_queue.c:172
>  ima_add_template_entry+0x52b/0x870 security/integrity/ima/ima_queue.c:172
>  ima_store_template security/integrity/ima/ima_api.c:122 [inline]
>  ima_store_measurement+0x371/0x8d0 security/integrity/ima/ima_api.c:376
>  process_measurement+0x2c6e/0x3ef0 security/integrity/ima/ima_main.c:367
>  ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3643 [inline]
>  path_openat+0x4d09/0x5ad0 fs/namei.c:3798
>  do_filp_open+0x20d/0x590 fs/namei.c:3825
>  do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
>  do_sys_open fs/open.c:1419 [inline]
>  __do_sys_open fs/open.c:1427 [inline]
>  __se_sys_open fs/open.c:1423 [inline]
>  __x64_sys_open+0x275/0x2d0 fs/open.c:1423
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
> 
> <Zero or more stacks not recorded to save memory>
> 
> Uninit was stored to memory at:
>  sha256_transform lib/crypto/sha256.c:117 [inline]
>  sha256_transform_blocks+0x2dbf/0x2e80 lib/crypto/sha256.c:127
>  lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
>  sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
>  crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
>  crypto_shash_update+0x75/0xa0 crypto/shash.c:70
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
>  process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3643 [inline]
>  path_openat+0x4d09/0x5ad0 fs/namei.c:3798
>  do_filp_open+0x20d/0x590 fs/namei.c:3825
>  do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
>  do_sys_open fs/open.c:1419 [inline]
>  __do_sys_open fs/open.c:1427 [inline]
>  __se_sys_open fs/open.c:1423 [inline]
>  __x64_sys_open+0x275/0x2d0 fs/open.c:1423
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
> 
> Uninit was stored to memory at:
>  sha256_transform lib/crypto/sha256.c:117 [inline]
>  sha256_transform_blocks+0x2dbf/0x2e80 lib/crypto/sha256.c:127
>  lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
>  sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
>  crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
>  crypto_shash_update+0x75/0xa0 crypto/shash.c:70
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
>  process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3643 [inline]
>  path_openat+0x4d09/0x5ad0 fs/namei.c:3798
>  do_filp_open+0x20d/0x590 fs/namei.c:3825
>  do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
>  do_sys_open fs/open.c:1419 [inline]
>  __do_sys_open fs/open.c:1427 [inline]
>  __se_sys_open fs/open.c:1423 [inline]
>  __x64_sys_open+0x275/0x2d0 fs/open.c:1423
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
> 
> Uninit was stored to memory at:
>  BLEND_OP lib/crypto/sha256.c:61 [inline]
>  sha256_transform lib/crypto/sha256.c:91 [inline]
>  sha256_transform_blocks+0xf33/0x2e80 lib/crypto/sha256.c:127
>  lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
>  sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
>  crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
>  crypto_shash_update+0x75/0xa0 crypto/shash.c:70
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
>  process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3643 [inline]
>  path_openat+0x4d09/0x5ad0 fs/namei.c:3798
>  do_filp_open+0x20d/0x590 fs/namei.c:3825
>  do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
>  do_sys_open fs/open.c:1419 [inline]
>  __do_sys_open fs/open.c:1427 [inline]
>  __se_sys_open fs/open.c:1423 [inline]
>  __x64_sys_open+0x275/0x2d0 fs/open.c:1423
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
> 
> Uninit was stored to memory at:
>  BLEND_OP lib/crypto/sha256.c:61 [inline]
>  sha256_transform lib/crypto/sha256.c:92 [inline]
>  sha256_transform_blocks+0xf7d/0x2e80 lib/crypto/sha256.c:127
>  lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
>  sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
>  crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
>  crypto_shash_update+0x75/0xa0 crypto/shash.c:70
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
>  process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3643 [inline]
>  path_openat+0x4d09/0x5ad0 fs/namei.c:3798
>  do_filp_open+0x20d/0x590 fs/namei.c:3825
>  do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
>  do_sys_open fs/open.c:1419 [inline]
>  __do_sys_open fs/open.c:1427 [inline]
>  __se_sys_open fs/open.c:1423 [inline]
>  __x64_sys_open+0x275/0x2d0 fs/open.c:1423
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
> 
> Uninit was stored to memory at:
>  BLEND_OP lib/crypto/sha256.c:61 [inline]
>  sha256_transform lib/crypto/sha256.c:93 [inline]
>  sha256_transform_blocks+0xfb5/0x2e80 lib/crypto/sha256.c:127
>  lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
>  sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
>  crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
>  crypto_shash_update+0x75/0xa0 crypto/shash.c:70
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
>  process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3643 [inline]
>  path_openat+0x4d09/0x5ad0 fs/namei.c:3798
>  do_filp_open+0x20d/0x590 fs/namei.c:3825
>  do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
>  do_sys_open fs/open.c:1419 [inline]
>  __do_sys_open fs/open.c:1427 [inline]
>  __se_sys_open fs/open.c:1423 [inline]
>  __x64_sys_open+0x275/0x2d0 fs/open.c:1423
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
> 
> Uninit was stored to memory at:
>  LOAD_OP lib/crypto/sha256.c:56 [inline]
>  sha256_transform lib/crypto/sha256.c:82 [inline]
>  sha256_transform_blocks+0x2c35/0x2e80 lib/crypto/sha256.c:127
>  lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
>  sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
>  crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
>  crypto_shash_update+0x75/0xa0 crypto/shash.c:70
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
>  process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3643 [inline]
>  path_openat+0x4d09/0x5ad0 fs/namei.c:3798
>  do_filp_open+0x20d/0x590 fs/namei.c:3825
>  do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
>  do_sys_open fs/open.c:1419 [inline]
>  __do_sys_open fs/open.c:1427 [inline]
>  __se_sys_open fs/open.c:1423 [inline]
>  __x64_sys_open+0x275/0x2d0 fs/open.c:1423
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b

If I understood what the report is saying (ima_calc_file_hash_tfm()):

	while (offset < i_size) {
		int rbuf_len;

		rbuf_len = integrity_kernel_read(file, offset, rbuf, PAGE_SIZE);
		if (rbuf_len < 0) {
			rc = rbuf_len;
			break;
		}
		if (rbuf_len == 0) {	/* unexpected EOF */
			rc = -EINVAL;
			break;
		}
		offset += rbuf_len;

		rc = crypto_shash_update(shash, rbuf, rbuf_len);
		if (rc)
			break;
	}

we are reading a non-initialized rbuf, which should not happen because
integrity_kernel_read() returned a positive value (success).

The other information we have is that the filesystem in question uses
generic_file_read_iter() as read_iter method.

I would add the VFS people in CC, in case they have some ideas.

Thanks

Roberto

> Uninit was stored to memory at:
>  memcpy_to_iter lib/iov_iter.c:65 [inline]
>  iterate_kvec include/linux/iov_iter.h:85 [inline]
>  iterate_and_advance2 include/linux/iov_iter.h:251 [inline]
>  iterate_and_advance include/linux/iov_iter.h:271 [inline]
>  _copy_to_iter+0x125a/0x2520 lib/iov_iter.c:186
>  copy_page_to_iter+0x419/0x870 lib/iov_iter.c:381
>  copy_folio_to_iter include/linux/uio.h:181 [inline]
>  filemap_read+0xbf4/0x14d0 mm/filemap.c:2654
>  generic_file_read_iter+0x136/0xad0 mm/filemap.c:2784
>  __kernel_read+0x724/0xce0 fs/read_write.c:434
>  integrity_kernel_read+0x77/0x90 security/integrity/iint.c:221
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0x1743/0x3cc0 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
>  process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3643 [inline]
>  path_openat+0x4d09/0x5ad0 fs/namei.c:3798
>  do_filp_open+0x20d/0x590 fs/namei.c:3825
>  do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
>  do_sys_open fs/open.c:1419 [inline]
>  __do_sys_open fs/open.c:1427 [inline]
>  __se_sys_open fs/open.c:1423 [inline]
>  __x64_sys_open+0x275/0x2d0 fs/open.c:1423
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
> 
> Uninit was created at:
>  __alloc_pages+0x9a6/0xe00 mm/page_alloc.c:4590
>  alloc_pages_mpol+0x62b/0x9d0 mm/mempolicy.c:2133
>  alloc_pages mm/mempolicy.c:2204 [inline]
>  folio_alloc+0x1da/0x380 mm/mempolicy.c:2211
>  filemap_alloc_folio+0xa5/0x430 mm/filemap.c:975
>  page_cache_ra_unbounded+0x2cc/0x960 mm/readahead.c:247
>  do_page_cache_ra mm/readahead.c:299 [inline]
>  page_cache_ra_order+0xe31/0xee0 mm/readahead.c:544
>  ondemand_readahead+0x157d/0x1750 mm/readahead.c:666
>  page_cache_sync_ra+0x724/0x760 mm/readahead.c:693
>  page_cache_sync_readahead include/linux/pagemap.h:1300 [inline]
>  filemap_get_pages+0x4c4/0x2bd0 mm/filemap.c:2498
>  filemap_read+0x59e/0x14d0 mm/filemap.c:2594
>  generic_file_read_iter+0x136/0xad0 mm/filemap.c:2784
>  __kernel_read+0x724/0xce0 fs/read_write.c:434
>  integrity_kernel_read+0x77/0x90 security/integrity/iint.c:221
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0x1743/0x3cc0 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
>  process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3643 [inline]
>  path_openat+0x4d09/0x5ad0 fs/namei.c:3798
>  do_filp_open+0x20d/0x590 fs/namei.c:3825
>  do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
>  do_sys_open fs/open.c:1419 [inline]
>  __do_sys_open fs/open.c:1427 [inline]
>  __se_sys_open fs/open.c:1423 [inline]
>  __x64_sys_open+0x275/0x2d0 fs/open.c:1423
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
> 
> CPU: 1 PID: 9243 Comm: syz-executor.3 Not tainted 6.8.0-rc4-syzkaller-00180-g4f5e5092fdbf #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
> =====================================================
> 
> 
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
> 
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> 
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
> 
> If you want to overwrite report's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
> 
> If the report is a duplicate of another one, reply with:
> #syz dup: exact-subject-of-another-report
> 
> If you want to undo deduplication, reply with:
> #syz undup


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [syzbot] [lsm?] [integrity?] KMSAN: uninit-value in ima_add_template_entry
  2024-02-20  6:41 [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry syzbot
  2024-02-20 10:40 ` Roberto Sassu
@ 2024-03-02 22:01 ` syzbot
  1 sibling, 0 replies; 12+ messages in thread
From: syzbot @ 2024-03-02 22:01 UTC (permalink / raw)
  To: dmitry.kasatkin, eric.snowberg, jmorris, linux-fsdevel,
	linux-integrity, linux-kernel, linux-security-module, paul,
	roberto.sassu, roberto.sassu, serge, syzkaller-bugs, zohar

syzbot has found a reproducer for the following issue on:

HEAD commit:    5ad3cb0ed525 Merge tag 'for-v6.8-rc2' of git://git.kernel...
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=15fdefac180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=80c7a82a572c0de3
dashboard link: https://syzkaller.appspot.com/bug?extid=7bc44a489f0ef0670bd5
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11917b26180000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1256096a180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a148235ac5b1/disk-5ad3cb0e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4b06f4d02ad6/vmlinux-5ad3cb0e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7fff06beed25/bzImage-5ad3cb0e.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/adece4ed9c9c/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com

erofs: (device loop0): mounted with root inode @ nid 36.
=====================================================
BUG: KMSAN: uninit-value in ima_add_template_entry+0x52b/0x870 security/integrity/ima/ima_queue.c:172
 ima_add_template_entry+0x52b/0x870 security/integrity/ima/ima_queue.c:172
 ima_store_template security/integrity/ima/ima_api.c:122 [inline]
 ima_store_measurement+0x371/0x8d0 security/integrity/ima/ima_api.c:376
 process_measurement+0x2c6e/0x3ef0 security/integrity/ima/ima_main.c:367
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3647 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3802
 do_filp_open+0x20d/0x590 fs/namei.c:3829
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

<Zero or more stacks not recorded to save memory>

Uninit was stored to memory at:
 sha256_transform lib/crypto/sha256.c:117 [inline]
 sha256_transform_blocks+0x2dbf/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3647 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3802
 do_filp_open+0x20d/0x590 fs/namei.c:3829
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 sha256_transform lib/crypto/sha256.c:117 [inline]
 sha256_transform_blocks+0x2dbf/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3647 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3802
 do_filp_open+0x20d/0x590 fs/namei.c:3829
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 BLEND_OP lib/crypto/sha256.c:61 [inline]
 sha256_transform lib/crypto/sha256.c:91 [inline]
 sha256_transform_blocks+0xf33/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3647 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3802
 do_filp_open+0x20d/0x590 fs/namei.c:3829
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 BLEND_OP lib/crypto/sha256.c:61 [inline]
 sha256_transform lib/crypto/sha256.c:92 [inline]
 sha256_transform_blocks+0xf7d/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3647 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3802
 do_filp_open+0x20d/0x590 fs/namei.c:3829
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 BLEND_OP lib/crypto/sha256.c:61 [inline]
 sha256_transform lib/crypto/sha256.c:93 [inline]
 sha256_transform_blocks+0xfb5/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3647 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3802
 do_filp_open+0x20d/0x590 fs/namei.c:3829
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 LOAD_OP lib/crypto/sha256.c:56 [inline]
 sha256_transform lib/crypto/sha256.c:82 [inline]
 sha256_transform_blocks+0x2c35/0x2e80 lib/crypto/sha256.c:127
 lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
 sha256_update+0x2fb/0x340 lib/crypto/sha256.c:136
 crypto_sha256_update+0x37/0x60 crypto/sha256_generic.c:39
 crypto_shash_update+0x75/0xa0 crypto/shash.c:70
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:496 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1816/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3647 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3802
 do_filp_open+0x20d/0x590 fs/namei.c:3829
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 memcpy_to_iter lib/iov_iter.c:65 [inline]
 iterate_kvec include/linux/iov_iter.h:85 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:251 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x125a/0x2520 lib/iov_iter.c:186
 copy_page_to_iter+0x419/0x870 lib/iov_iter.c:381
 copy_folio_to_iter include/linux/uio.h:181 [inline]
 filemap_read+0xbf4/0x14d0 mm/filemap.c:2654
 generic_file_read_iter+0x136/0xad0 mm/filemap.c:2784
 __kernel_read+0x724/0xce0 fs/read_write.c:434
 integrity_kernel_read+0x77/0x90 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1743/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3647 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3802
 do_filp_open+0x20d/0x590 fs/namei.c:3829
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 __alloc_pages+0x9a6/0xe00 mm/page_alloc.c:4590
 alloc_pages_mpol+0x62b/0x9d0 mm/mempolicy.c:2133
 alloc_pages mm/mempolicy.c:2204 [inline]
 folio_alloc+0x1da/0x380 mm/mempolicy.c:2211
 filemap_alloc_folio+0xa5/0x430 mm/filemap.c:975
 page_cache_ra_unbounded+0x2cc/0x960 mm/readahead.c:247
 do_page_cache_ra mm/readahead.c:299 [inline]
 page_cache_ra_order+0xe31/0xee0 mm/readahead.c:544
 ondemand_readahead+0x157d/0x1750 mm/readahead.c:666
 page_cache_sync_ra+0x724/0x760 mm/readahead.c:693
 page_cache_sync_readahead include/linux/pagemap.h:1300 [inline]
 filemap_get_pages+0x4c4/0x2bd0 mm/filemap.c:2498
 filemap_read+0x59e/0x14d0 mm/filemap.c:2594
 generic_file_read_iter+0x136/0xad0 mm/filemap.c:2784
 __kernel_read+0x724/0xce0 fs/read_write.c:434
 integrity_kernel_read+0x77/0x90 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0x1743/0x3cc0 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x44d/0xdd0 security/integrity/ima/ima_api.c:290
 process_measurement+0x2936/0x3ef0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xb3/0x100 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3647 [inline]
 path_openat+0x4d09/0x5ad0 fs/namei.c:3802
 do_filp_open+0x20d/0x590 fs/namei.c:3829
 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_open fs/open.c:1427 [inline]
 __se_sys_open fs/open.c:1423 [inline]
 __x64_sys_open+0x275/0x2d0 fs/open.c:1423
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

CPU: 0 PID: 5012 Comm: syz-executor394 Not tainted 6.8.0-rc6-syzkaller-00238-g5ad3cb0ed525 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
=====================================================


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry
  2024-02-20 10:40 ` Roberto Sassu
@ 2024-03-03 14:54   ` Tetsuo Handa
  2024-03-03 23:53     ` Gao Xiang
                       ` (2 more replies)
  0 siblings, 3 replies; 12+ messages in thread
From: Tetsuo Handa @ 2024-03-03 14:54 UTC (permalink / raw)
  To: syzbot, syzkaller-bugs, Gao Xiang, Chao Yu, Yue Hu, Jeffle Xu
  Cc: linux-kernel, linux-erofs

On 2024/02/20 19:40, Roberto Sassu wrote:
> On Mon, 2024-02-19 at 22:41 -0800, syzbot wrote:
>> Hello,
>>
>> syzbot found the following issue on:
>>
>> HEAD commit:    4f5e5092fdbf Merge tag 'net-6.8-rc5' of git://git.kernel.o..
>> git tree:       upstream
>> console output: https://syzkaller.appspot.com/x/log.txt?x=135ba81c180000
>> kernel config:  https://syzkaller.appspot.com/x/.config?x=e3dd779fba027968
>> dashboard link: https://syzkaller.appspot.com/bug?extid=7bc44a489f0ef0670bd5
>> compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

> I would add the VFS people in CC, in case they have some ideas.

This is an erofs bug. Since the filesystem image in the reproducer
is crafted, decompression generates bogus result and
z_erofs_transform_plain() misbehaves.

You can obtain a single-threaded reproducer from
https://syzkaller.appspot.com/x/repro.c?x=1256096a180000 with below diff.

----------------------------------------
--- old/1256096a180000.c
+++ new/1256096a180000.c
@@ -676,6 +676,6 @@
   syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
           /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
           /*offset=*/0ul);
-  loop();
+  execute_one();
   return 0;
 }
----------------------------------------

With CONFIG_EROFS_FS_DEBUG=y, the reproducer hits DBG_BUGON().
With debug printk() shown below, you can get output shown below.

----------------------------------------
diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index d4cee95af14c..f221133a0731 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -323,7 +323,11 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
 	unsigned int cur = 0, ni = 0, no, pi, po, insz, cnt;
 	u8 *kin;
 
-	DBG_BUGON(rq->outputsize > rq->inputsize);
+	if (rq->outputsize > rq->inputsize) {
+		pr_err("rq->inputsize=%u rq->outputsize=%u\n", rq->inputsize, rq->outputsize);
+		pr_err("rq->pageofs_in=%u rq->pageofs_out=%u\n", rq->pageofs_in, rq->pageofs_out);
+		pr_err("nrpages_in=%u nrpages_out=%u\n", nrpages_in, nrpages_out);
+	}
 	if (rq->alg == Z_EROFS_COMPRESSION_INTERLACED) {
 		cur = bs - (rq->pageofs_out & (bs - 1));
 		pi = (rq->pageofs_in + rq->inputsize - cur) & ~PAGE_MASK;
@@ -352,7 +356,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
 		do {
 			no = (rq->pageofs_out + cur + pi) >> PAGE_SHIFT;
 			po = (rq->pageofs_out + cur + pi) & ~PAGE_MASK;
-			DBG_BUGON(no >= nrpages_out);
+			if (no >= nrpages_out)
+				pr_err("no=%u nrpages_out=%u\n", no, nrpages_out);
 			cnt = min(insz - pi, PAGE_SIZE - po);
 			if (rq->out[no] == rq->in[ni]) {
 				memmove(kin + po,
@@ -366,7 +371,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
 		} while (pi < insz);
 		kunmap_local(kin);
 	}
-	DBG_BUGON(ni > nrpages_in);
+	if (ni > nrpages_in)
+		pr_err("ni=%u nrpages_in=%u\n", ni, nrpages_in);
 	return 0;
 }
 
----------------------------------------

----------------------------------------
[  138.991810][ T2983] loop0: detected capacity change from 0 to 16
[  139.804002][ T2983] erofs: (device loop0): mounted with root inode @ nid 36.
[  139.810464][   T87] erofs: rq->inputsize=4096 rq->outputsize=8194
[  139.821540][   T87] erofs: rq->pageofs_in=0 rq->pageofs_out=0
[  139.824347][   T87] erofs: nrpages_in=1 nrpages_out=3
[  139.827008][   T87] erofs: ni=3 nrpages_in=1
[  139.873777][ T2983] =====================================================
[  139.881268][ T2983] BUG: KMSAN: uninit-value in ima_add_template_entry+0x626/0xa80
----------------------------------------

#syz set subsystems: erofs


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* Re: [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry
  2024-03-03 14:54   ` Tetsuo Handa
@ 2024-03-03 23:53     ` Gao Xiang
  2024-03-04  3:53     ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Gao Xiang
  2024-03-04  8:15     ` [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry Roberto Sassu
  2 siblings, 0 replies; 12+ messages in thread
From: Gao Xiang @ 2024-03-03 23:53 UTC (permalink / raw)
  To: Tetsuo Handa, syzbot, syzkaller-bugs, Gao Xiang, Chao Yu, Yue Hu,
	Jeffle Xu
  Cc: linux-kernel, linux-erofs



On 2024/3/3 22:54, Tetsuo Handa wrote:
> On 2024/02/20 19:40, Roberto Sassu wrote:
>> On Mon, 2024-02-19 at 22:41 -0800, syzbot wrote:
>>> Hello,
>>>
>>> syzbot found the following issue on:
>>>
>>> HEAD commit:    4f5e5092fdbf Merge tag 'net-6.8-rc5' of git://git.kernel.o..
>>> git tree:       upstream
>>> console output: https://syzkaller.appspot.com/x/log.txt?x=135ba81c180000
>>> kernel config:  https://syzkaller.appspot.com/x/.config?x=e3dd779fba027968
>>> dashboard link: https://syzkaller.appspot.com/bug?extid=7bc44a489f0ef0670bd5
>>> compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> 
>> I would add the VFS people in CC, in case they have some ideas.
> 
> This is an erofs bug. Since the filesystem image in the reproducer
> is crafted, decompression generates bogus result and
> z_erofs_transform_plain() misbehaves.

Yes, thanks for looking into this.  It seems it was introduced by
a new commit 1ca01520148a this cycle, let me find more clues and
make a fix for this.

Thanks,
Gao Xiang

> 
> You can obtain a single-threaded reproducer from
> https://syzkaller.appspot.com/x/repro.c?x=1256096a180000 with below diff.
> 
> ----------------------------------------
> --- old/1256096a180000.c
> +++ new/1256096a180000.c
> @@ -676,6 +676,6 @@
>     syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
>             /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
>             /*offset=*/0ul);
> -  loop();
> +  execute_one();
>     return 0;
>   }
> ----------------------------------------
> 
> With CONFIG_EROFS_FS_DEBUG=y, the reproducer hits DBG_BUGON().
> With debug printk() shown below, you can get output shown below.
> 
> ----------------------------------------
> diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
> index d4cee95af14c..f221133a0731 100644
> --- a/fs/erofs/decompressor.c
> +++ b/fs/erofs/decompressor.c
> @@ -323,7 +323,11 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
>   	unsigned int cur = 0, ni = 0, no, pi, po, insz, cnt;
>   	u8 *kin;
>   
> -	DBG_BUGON(rq->outputsize > rq->inputsize);
> +	if (rq->outputsize > rq->inputsize) {
> +		pr_err("rq->inputsize=%u rq->outputsize=%u\n", rq->inputsize, rq->outputsize);
> +		pr_err("rq->pageofs_in=%u rq->pageofs_out=%u\n", rq->pageofs_in, rq->pageofs_out);
> +		pr_err("nrpages_in=%u nrpages_out=%u\n", nrpages_in, nrpages_out);
> +	}
>   	if (rq->alg == Z_EROFS_COMPRESSION_INTERLACED) {
>   		cur = bs - (rq->pageofs_out & (bs - 1));
>   		pi = (rq->pageofs_in + rq->inputsize - cur) & ~PAGE_MASK;
> @@ -352,7 +356,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
>   		do {
>   			no = (rq->pageofs_out + cur + pi) >> PAGE_SHIFT;
>   			po = (rq->pageofs_out + cur + pi) & ~PAGE_MASK;
> -			DBG_BUGON(no >= nrpages_out);
> +			if (no >= nrpages_out)
> +				pr_err("no=%u nrpages_out=%u\n", no, nrpages_out);
>   			cnt = min(insz - pi, PAGE_SIZE - po);
>   			if (rq->out[no] == rq->in[ni]) {
>   				memmove(kin + po,
> @@ -366,7 +371,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
>   		} while (pi < insz);
>   		kunmap_local(kin);
>   	}
> -	DBG_BUGON(ni > nrpages_in);
> +	if (ni > nrpages_in)
> +		pr_err("ni=%u nrpages_in=%u\n", ni, nrpages_in);
>   	return 0;
>   }
>   
> ----------------------------------------
> 
> ----------------------------------------
> [  138.991810][ T2983] loop0: detected capacity change from 0 to 16
> [  139.804002][ T2983] erofs: (device loop0): mounted with root inode @ nid 36.
> [  139.810464][   T87] erofs: rq->inputsize=4096 rq->outputsize=8194
> [  139.821540][   T87] erofs: rq->pageofs_in=0 rq->pageofs_out=0
> [  139.824347][   T87] erofs: nrpages_in=1 nrpages_out=3
> [  139.827008][   T87] erofs: ni=3 nrpages_in=1
> [  139.873777][ T2983] =====================================================
> [  139.881268][ T2983] BUG: KMSAN: uninit-value in ima_add_template_entry+0x626/0xa80
> ----------------------------------------
> 
> #syz set subsystems: erofs

^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH] erofs: fix uninitialized page cache reported by KMSAN
  2024-03-03 14:54   ` Tetsuo Handa
  2024-03-03 23:53     ` Gao Xiang
@ 2024-03-04  3:53     ` Gao Xiang
  2024-03-04  6:04       ` Gao Xiang
                         ` (3 more replies)
  2024-03-04  8:15     ` [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry Roberto Sassu
  2 siblings, 4 replies; 12+ messages in thread
From: Gao Xiang @ 2024-03-04  3:53 UTC (permalink / raw)
  To: linux-erofs
  Cc: LKML, linux-fsdevel, Tetsuo Handa, Roberto Sassu, syzkaller-bugs,
	Gao Xiang, syzbot+7bc44a489f0ef0670bd5

syzbot reports a KMSAN reproducer [1] which generates a crafted
filesystem image and causes IMA to read uninitialized page cache.

Later, (rq->outputsize > rq->inputsize) will be formally supported
after either large uncompressed pclusters (> block size) or big
lclusters are landed.  However, currently there is no way to generate
such filesystems by using mkfs.erofs.

Thus, let's mark this condition as unsupported for now.

[1] https://lore.kernel.org/r/0000000000002be12a0611ca7ff8@google.com

Reported-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com
Fixes: 1ca01520148a ("erofs: refine z_erofs_transform_plain() for sub-page block support")
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
 fs/erofs/decompressor.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index d4cee95af14c..2ec9b2bb628d 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -323,7 +323,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
 	unsigned int cur = 0, ni = 0, no, pi, po, insz, cnt;
 	u8 *kin;
 
-	DBG_BUGON(rq->outputsize > rq->inputsize);
+	if (rq->outputsize > rq->inputsize)
+		return -EOPNOTSUPP;
 	if (rq->alg == Z_EROFS_COMPRESSION_INTERLACED) {
 		cur = bs - (rq->pageofs_out & (bs - 1));
 		pi = (rq->pageofs_in + rq->inputsize - cur) & ~PAGE_MASK;
-- 
2.39.3


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* Re: [PATCH] erofs: fix uninitialized page cache reported by KMSAN
  2024-03-04  3:53     ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Gao Xiang
@ 2024-03-04  6:04       ` Gao Xiang
  2024-03-04  6:51         ` [syzbot] [erofs] KMSAN: uninit-value in ima_add_template_entry syzbot
  2024-03-04 17:51       ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Sandeep Dhavale
                         ` (2 subsequent siblings)
  3 siblings, 1 reply; 12+ messages in thread
From: Gao Xiang @ 2024-03-04  6:04 UTC (permalink / raw)
  To: linux-erofs, syzkaller-bugs
  Cc: syzbot+7bc44a489f0ef0670bd5, Tetsuo Handa, LKML, Roberto Sassu

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git dev-test

On 2024/3/4 11:53, Gao Xiang wrote:
> syzbot reports a KMSAN reproducer [1] which generates a crafted
> filesystem image and causes IMA to read uninitialized page cache.
> 
> Later, (rq->outputsize > rq->inputsize) will be formally supported
> after either large uncompressed pclusters (> block size) or big
> lclusters are landed.  However, currently there is no way to generate
> such filesystems by using mkfs.erofs.
> 
> Thus, let's mark this condition as unsupported for now.
> 
> [1] https://lore.kernel.org/r/0000000000002be12a0611ca7ff8@google.com
> 
> Reported-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com
> Fixes: 1ca01520148a ("erofs: refine z_erofs_transform_plain() for sub-page block support")
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
> ---
>   fs/erofs/decompressor.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
> index d4cee95af14c..2ec9b2bb628d 100644
> --- a/fs/erofs/decompressor.c
> +++ b/fs/erofs/decompressor.c
> @@ -323,7 +323,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
>   	unsigned int cur = 0, ni = 0, no, pi, po, insz, cnt;
>   	u8 *kin;
>   
> -	DBG_BUGON(rq->outputsize > rq->inputsize);
> +	if (rq->outputsize > rq->inputsize)
> +		return -EOPNOTSUPP;
>   	if (rq->alg == Z_EROFS_COMPRESSION_INTERLACED) {
>   		cur = bs - (rq->pageofs_out & (bs - 1));
>   		pi = (rq->pageofs_in + rq->inputsize - cur) & ~PAGE_MASK;

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [syzbot] [erofs] KMSAN: uninit-value in ima_add_template_entry
  2024-03-04  6:04       ` Gao Xiang
@ 2024-03-04  6:51         ` syzbot
  0 siblings, 0 replies; 12+ messages in thread
From: syzbot @ 2024-03-04  6:51 UTC (permalink / raw)
  To: hsiangkao, linux-erofs, linux-kernel, penguin-kernel,
	roberto.sassu, syzkaller-bugs

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com

Tested on:

commit:         4288d8d1 erofs: fix uninitialized page cache reported ..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git dev-test
console output: https://syzkaller.appspot.com/x/log.txt?x=10893754180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=db27810a659d0b3d
dashboard link: https://syzkaller.appspot.com/bug?extid=7bc44a489f0ef0670bd5
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry
  2024-03-03 14:54   ` Tetsuo Handa
  2024-03-03 23:53     ` Gao Xiang
  2024-03-04  3:53     ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Gao Xiang
@ 2024-03-04  8:15     ` Roberto Sassu
  2 siblings, 0 replies; 12+ messages in thread
From: Roberto Sassu @ 2024-03-04  8:15 UTC (permalink / raw)
  To: Tetsuo Handa, syzbot, syzkaller-bugs, Gao Xiang, Chao Yu, Yue Hu,
	Jeffle Xu
  Cc: linux-kernel, linux-erofs, linux-integrity, zohar

On Sun, 2024-03-03 at 23:54 +0900, Tetsuo Handa wrote:
> On 2024/02/20 19:40, Roberto Sassu wrote:
> > On Mon, 2024-02-19 at 22:41 -0800, syzbot wrote:
> > > Hello,
> > > 
> > > syzbot found the following issue on:
> > > 
> > > HEAD commit:    4f5e5092fdbf Merge tag 'net-6.8-rc5' of git://git.kernel.o..
> > > git tree:       upstream
> > > console output: https://syzkaller.appspot.com/x/log.txt?x=135ba81c180000
> > > kernel config:  https://syzkaller.appspot.com/x/.config?x=e3dd779fba027968
> > > dashboard link: https://syzkaller.appspot.com/bug?extid=7bc44a489f0ef0670bd5
> > > compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> 
> > I would add the VFS people in CC, in case they have some ideas.
> 
> This is an erofs bug. Since the filesystem image in the reproducer
> is crafted, decompression generates bogus result and
> z_erofs_transform_plain() misbehaves.

Thank you Tetsuo, and Gao Xiang for fixing it!

Roberto

> You can obtain a single-threaded reproducer from
> https://syzkaller.appspot.com/x/repro.c?x=1256096a180000 with below diff.
> 
> ----------------------------------------
> --- old/1256096a180000.c
> +++ new/1256096a180000.c
> @@ -676,6 +676,6 @@
>    syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
>            /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
>            /*offset=*/0ul);
> -  loop();
> +  execute_one();
>    return 0;
>  }
> ----------------------------------------
> 
> With CONFIG_EROFS_FS_DEBUG=y, the reproducer hits DBG_BUGON().
> With debug printk() shown below, you can get output shown below.
> 
> ----------------------------------------
> diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
> index d4cee95af14c..f221133a0731 100644
> --- a/fs/erofs/decompressor.c
> +++ b/fs/erofs/decompressor.c
> @@ -323,7 +323,11 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
>  	unsigned int cur = 0, ni = 0, no, pi, po, insz, cnt;
>  	u8 *kin;
>  
> -	DBG_BUGON(rq->outputsize > rq->inputsize);
> +	if (rq->outputsize > rq->inputsize) {
> +		pr_err("rq->inputsize=%u rq->outputsize=%u\n", rq->inputsize, rq->outputsize);
> +		pr_err("rq->pageofs_in=%u rq->pageofs_out=%u\n", rq->pageofs_in, rq->pageofs_out);
> +		pr_err("nrpages_in=%u nrpages_out=%u\n", nrpages_in, nrpages_out);
> +	}
>  	if (rq->alg == Z_EROFS_COMPRESSION_INTERLACED) {
>  		cur = bs - (rq->pageofs_out & (bs - 1));
>  		pi = (rq->pageofs_in + rq->inputsize - cur) & ~PAGE_MASK;
> @@ -352,7 +356,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
>  		do {
>  			no = (rq->pageofs_out + cur + pi) >> PAGE_SHIFT;
>  			po = (rq->pageofs_out + cur + pi) & ~PAGE_MASK;
> -			DBG_BUGON(no >= nrpages_out);
> +			if (no >= nrpages_out)
> +				pr_err("no=%u nrpages_out=%u\n", no, nrpages_out);
>  			cnt = min(insz - pi, PAGE_SIZE - po);
>  			if (rq->out[no] == rq->in[ni]) {
>  				memmove(kin + po,
> @@ -366,7 +371,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
>  		} while (pi < insz);
>  		kunmap_local(kin);
>  	}
> -	DBG_BUGON(ni > nrpages_in);
> +	if (ni > nrpages_in)
> +		pr_err("ni=%u nrpages_in=%u\n", ni, nrpages_in);
>  	return 0;
>  }
>  
> ----------------------------------------
> 
> ----------------------------------------
> [  138.991810][ T2983] loop0: detected capacity change from 0 to 16
> [  139.804002][ T2983] erofs: (device loop0): mounted with root inode @ nid 36.
> [  139.810464][   T87] erofs: rq->inputsize=4096 rq->outputsize=8194
> [  139.821540][   T87] erofs: rq->pageofs_in=0 rq->pageofs_out=0
> [  139.824347][   T87] erofs: nrpages_in=1 nrpages_out=3
> [  139.827008][   T87] erofs: ni=3 nrpages_in=1
> [  139.873777][ T2983] =====================================================
> [  139.881268][ T2983] BUG: KMSAN: uninit-value in ima_add_template_entry+0x626/0xa80
> ----------------------------------------
> 
> #syz set subsystems: erofs


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH] erofs: fix uninitialized page cache reported by KMSAN
  2024-03-04  3:53     ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Gao Xiang
  2024-03-04  6:04       ` Gao Xiang
@ 2024-03-04 17:51       ` Sandeep Dhavale
  2024-03-05  2:17       ` Yue Hu
  2024-03-07  1:04       ` Chao Yu
  3 siblings, 0 replies; 12+ messages in thread
From: Sandeep Dhavale @ 2024-03-04 17:51 UTC (permalink / raw)
  To: Gao Xiang
  Cc: linux-erofs, syzbot+7bc44a489f0ef0670bd5, Tetsuo Handa,
	syzkaller-bugs, LKML, Roberto Sassu, linux-fsdevel

On Sun, Mar 3, 2024 at 7:54 PM Gao Xiang <hsiangkao@linux.alibaba.com> wrote:
>
> syzbot reports a KMSAN reproducer [1] which generates a crafted
> filesystem image and causes IMA to read uninitialized page cache.
>
> Later, (rq->outputsize > rq->inputsize) will be formally supported
> after either large uncompressed pclusters (> block size) or big
> lclusters are landed.  However, currently there is no way to generate
> such filesystems by using mkfs.erofs.
>
> Thus, let's mark this condition as unsupported for now.
>
> [1] https://lore.kernel.org/r/0000000000002be12a0611ca7ff8@google.com
>
> Reported-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com
> Fixes: 1ca01520148a ("erofs: refine z_erofs_transform_plain() for sub-page block support")
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
> ---
>  fs/erofs/decompressor.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
> index d4cee95af14c..2ec9b2bb628d 100644
> --- a/fs/erofs/decompressor.c
> +++ b/fs/erofs/decompressor.c
> @@ -323,7 +323,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
>         unsigned int cur = 0, ni = 0, no, pi, po, insz, cnt;
>         u8 *kin;
>
> -       DBG_BUGON(rq->outputsize > rq->inputsize);
> +       if (rq->outputsize > rq->inputsize)
> +               return -EOPNOTSUPP;
>         if (rq->alg == Z_EROFS_COMPRESSION_INTERLACED) {
>                 cur = bs - (rq->pageofs_out & (bs - 1));
>                 pi = (rq->pageofs_in + rq->inputsize - cur) & ~PAGE_MASK;
> --
> 2.39.3
>
LGTM.
Reviewed-by: Sandeep Dhavale <dhavale@google.com>

Thanks,
Sandeep.

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH] erofs: fix uninitialized page cache reported by KMSAN
  2024-03-04  3:53     ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Gao Xiang
  2024-03-04  6:04       ` Gao Xiang
  2024-03-04 17:51       ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Sandeep Dhavale
@ 2024-03-05  2:17       ` Yue Hu
  2024-03-07  1:04       ` Chao Yu
  3 siblings, 0 replies; 12+ messages in thread
From: Yue Hu @ 2024-03-05  2:17 UTC (permalink / raw)
  To: Gao Xiang
  Cc: linux-erofs, syzbot+7bc44a489f0ef0670bd5, Tetsuo Handa,
	syzkaller-bugs, LKML, Roberto Sassu, linux-fsdevel

On Mon,  4 Mar 2024 11:53:39 +0800
Gao Xiang <hsiangkao@linux.alibaba.com> wrote:

> syzbot reports a KMSAN reproducer [1] which generates a crafted
> filesystem image and causes IMA to read uninitialized page cache.
> 
> Later, (rq->outputsize > rq->inputsize) will be formally supported
> after either large uncompressed pclusters (> block size) or big
> lclusters are landed.  However, currently there is no way to generate
> such filesystems by using mkfs.erofs.
> 
> Thus, let's mark this condition as unsupported for now.
> 
> [1] https://lore.kernel.org/r/0000000000002be12a0611ca7ff8@google.com
> 
> Reported-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com
> Fixes: 1ca01520148a ("erofs: refine z_erofs_transform_plain() for sub-page block support")
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
> ---
>  fs/erofs/decompressor.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
> index d4cee95af14c..2ec9b2bb628d 100644
> --- a/fs/erofs/decompressor.c
> +++ b/fs/erofs/decompressor.c
> @@ -323,7 +323,8 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
>  	unsigned int cur = 0, ni = 0, no, pi, po, insz, cnt;
>  	u8 *kin;
>  
> -	DBG_BUGON(rq->outputsize > rq->inputsize);
> +	if (rq->outputsize > rq->inputsize)
> +		return -EOPNOTSUPP;
>  	if (rq->alg == Z_EROFS_COMPRESSION_INTERLACED) {
>  		cur = bs - (rq->pageofs_out & (bs - 1));
>  		pi = (rq->pageofs_in + rq->inputsize - cur) & ~PAGE_MASK;

Reviewed-by: Yue Hu <huyue2@coolpad.com>

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH] erofs: fix uninitialized page cache reported by KMSAN
  2024-03-04  3:53     ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Gao Xiang
                         ` (2 preceding siblings ...)
  2024-03-05  2:17       ` Yue Hu
@ 2024-03-07  1:04       ` Chao Yu
  3 siblings, 0 replies; 12+ messages in thread
From: Chao Yu @ 2024-03-07  1:04 UTC (permalink / raw)
  To: Gao Xiang, linux-erofs
  Cc: syzbot+7bc44a489f0ef0670bd5, Tetsuo Handa, syzkaller-bugs, LKML,
	Roberto Sassu, linux-fsdevel

On 2024/3/4 11:53, Gao Xiang wrote:
> syzbot reports a KMSAN reproducer [1] which generates a crafted
> filesystem image and causes IMA to read uninitialized page cache.
> 
> Later, (rq->outputsize > rq->inputsize) will be formally supported
> after either large uncompressed pclusters (> block size) or big
> lclusters are landed.  However, currently there is no way to generate
> such filesystems by using mkfs.erofs.
> 
> Thus, let's mark this condition as unsupported for now.
> 
> [1] https://lore.kernel.org/r/0000000000002be12a0611ca7ff8@google.com
> 
> Reported-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com
> Fixes: 1ca01520148a ("erofs: refine z_erofs_transform_plain() for sub-page block support")
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,

^ permalink raw reply	[flat|nested] 12+ messages in thread

end of thread, other threads:[~2024-03-07  1:04 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-02-20  6:41 [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry syzbot
2024-02-20 10:40 ` Roberto Sassu
2024-03-03 14:54   ` Tetsuo Handa
2024-03-03 23:53     ` Gao Xiang
2024-03-04  3:53     ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Gao Xiang
2024-03-04  6:04       ` Gao Xiang
2024-03-04  6:51         ` [syzbot] [erofs] KMSAN: uninit-value in ima_add_template_entry syzbot
2024-03-04 17:51       ` [PATCH] erofs: fix uninitialized page cache reported by KMSAN Sandeep Dhavale
2024-03-05  2:17       ` Yue Hu
2024-03-07  1:04       ` Chao Yu
2024-03-04  8:15     ` [syzbot] [integrity?] [lsm?] KMSAN: uninit-value in ima_add_template_entry Roberto Sassu
2024-03-02 22:01 ` [syzbot] [lsm?] [integrity?] " syzbot

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