[syzbot] [hfs?] KMSAN: uninit-value in hfs_free_fork

[syzbot] [hfs?] KMSAN: uninit-value in hfs_free_fork

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    b9158815de52 Merge tag 'char-misc-6.9-rc7' of git://git.ke..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=15154bff180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=bbf567496022057b
dashboard link: https://syzkaller.appspot.com/bug?extid=2e6fb1f89ce5e13cd02d
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=1262fb38980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1530bdc4980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7886d49e8de8/disk-b9158815.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7909f40ff65c/vmlinux-b9158815.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7641fb86043d/bzImage-b9158815.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/aeab32d02708/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2e6fb1f89ce5e13cd02d@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in __hfs_ext_read_extent fs/hfs/extent.c:160 [inline]
BUG: KMSAN: uninit-value in hfs_free_fork+0x6b4/0xa50 fs/hfs/extent.c:320
 __hfs_ext_read_extent fs/hfs/extent.c:160 [inline]
 hfs_free_fork+0x6b4/0xa50 fs/hfs/extent.c:320
 hfs_cat_delete+0x501/0xb90 fs/hfs/catalog.c:247
 hfs_remove+0x16a/0x2f0 fs/hfs/dir.c:262
 vfs_unlink+0x676/0xa30 fs/namei.c:4335
 do_unlinkat+0x823/0xe10 fs/namei.c:4399
 __do_sys_unlink fs/namei.c:4447 [inline]
 __se_sys_unlink fs/namei.c:4445 [inline]
 __x64_sys_unlink+0x78/0xb0 fs/namei.c:4445
 x64_sys_call+0x31c7/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:88
 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+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3804 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 __do_kmalloc_node mm/slub.c:3965 [inline]
 __kmalloc+0x6e4/0x1000 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 hfs_find_init+0x91/0x250 fs/hfs/bfind.c:21
 hfs_free_fork+0x3bb/0xa50 fs/hfs/extent.c:316
 hfs_cat_delete+0x501/0xb90 fs/hfs/catalog.c:247
 hfs_remove+0x16a/0x2f0 fs/hfs/dir.c:262
 vfs_unlink+0x676/0xa30 fs/namei.c:4335
 do_unlinkat+0x823/0xe10 fs/namei.c:4399
 __do_sys_unlink fs/namei.c:4447 [inline]
 __se_sys_unlink fs/namei.c:4445 [inline]
 __x64_sys_unlink+0x78/0xb0 fs/namei.c:4445
 x64_sys_call+0x31c7/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:88
 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+0x77/0x7f

CPU: 1 PID: 5043 Comm: syz-executor323 Not tainted 6.9.0-rc6-syzkaller-00290-gb9158815de52 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
=====================================================


---
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 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.

If you want to overwrite report's subsystems, reply with:
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(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

Re: [syzbot] [hfs?] KMSAN: uninit-value in hfs_free_fork

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KMSAN: uninit-value in hfs_free_fork

loop0: detected capacity change from 0 to 64
=====================================================
BUG: KMSAN: uninit-value in __hfs_ext_read_extent fs/hfs/extent.c:160 [inline]
BUG: KMSAN: uninit-value in hfs_free_fork+0x6b4/0xa50 fs/hfs/extent.c:320
 __hfs_ext_read_extent fs/hfs/extent.c:160 [inline]
 hfs_free_fork+0x6b4/0xa50 fs/hfs/extent.c:320
 hfs_cat_delete+0x501/0xb90 fs/hfs/catalog.c:247
 hfs_remove+0x16a/0x2f0 fs/hfs/dir.c:262
 vfs_unlink+0x676/0xa90 fs/namei.c:4469
 do_unlinkat+0x823/0xe10 fs/namei.c:4533
 __do_sys_unlink fs/namei.c:4581 [inline]
 __se_sys_unlink fs/namei.c:4579 [inline]
 __x64_sys_unlink+0x76/0xa0 fs/namei.c:4579
 x64_sys_call+0x30d3/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4091 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 __do_kmalloc_node mm/slub.c:4263 [inline]
 __kmalloc_noprof+0x661/0xf30 mm/slub.c:4276
 kmalloc_noprof include/linux/slab.h:882 [inline]
 hfs_find_init+0x91/0x250 fs/hfs/bfind.c:21
 hfs_free_fork+0x3bb/0xa50 fs/hfs/extent.c:316
 hfs_cat_delete+0x501/0xb90 fs/hfs/catalog.c:247
 hfs_remove+0x16a/0x2f0 fs/hfs/dir.c:262
 vfs_unlink+0x676/0xa90 fs/namei.c:4469
 do_unlinkat+0x823/0xe10 fs/namei.c:4533
 __do_sys_unlink fs/namei.c:4581 [inline]
 __se_sys_unlink fs/namei.c:4579 [inline]
 __x64_sys_unlink+0x76/0xa0 fs/namei.c:4579
 x64_sys_call+0x30d3/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 6057 Comm: syz.0.15 Not tainted 6.12.0-rc4-syzkaller-gc2ee9f594da8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
=====================================================


Tested on:

commit:         c2ee9f59 KVM: selftests: Fix build on on non-x86 archi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11d8ca5f980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=fa3d7fc2fd6ea40d
dashboard link: https://syzkaller.appspot.com/bug?extid=2e6fb1f89ce5e13cd02d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.

Re: [syzbot] [hfs?] KMSAN: uninit-value in hfs_free_fork

[Gianfranco Trad]

[-- Attachment #1: Type: text/plain, Size: 9 bytes --]

#syz test

[-- Attachment #2: 0001-hfs-use-kzalloc-in-hfs_find_init.patch --]
[-- Type: text/x-patch, Size: 770 bytes --]

From 0fb9dbd8a0e88e6e4011c9c97701f40b8d845831 Mon Sep 17 00:00:00 2001
From: Gianfranco Trad <gianf.trad@gmail.com>
Date: Wed, 23 Oct 2024 00:10:04 +0200
Subject: [PATCH] hfs: use kzalloc in hfs_find_init()

Signed-off-by: Gianfranco Trad <gianf.trad@gmail.com>
---
 fs/hfs/bfind.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/hfs/bfind.c b/fs/hfs/bfind.c
index ef9498a6e88a..c74d864bc29e 100644
--- a/fs/hfs/bfind.c
+++ b/fs/hfs/bfind.c
@@ -18,7 +18,7 @@ int hfs_find_init(struct hfs_btree *tree, struct hfs_find_data *fd)
 
 	fd->tree = tree;
 	fd->bnode = NULL;
-	ptr = kmalloc(tree->max_key_len * 2 + 4, GFP_KERNEL);
+	ptr = kzalloc(tree->max_key_len * 2 + 4, GFP_KERNEL);
 	if (!ptr)
 		return -ENOMEM;
 	fd->search_key = ptr;
-- 
2.43.0

Re: [syzbot] [hfs?] KMSAN: uninit-value in hfs_free_fork

[syzbot]

Hello,

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

Reported-by: syzbot+2e6fb1f89ce5e13cd02d@syzkaller.appspotmail.com
Tested-by: syzbot+2e6fb1f89ce5e13cd02d@syzkaller.appspotmail.com

Tested on:

commit:         c2ee9f59 KVM: selftests: Fix build on on non-x86 archi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12f4a640580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=fa3d7fc2fd6ea40d
dashboard link: https://syzkaller.appspot.com/bug?extid=2e6fb1f89ce5e13cd02d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10eb8287980000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [hfs?] KMSAN: uninit-value in hfs_free_fork

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KMSAN: uninit-value in hfs_free_fork

loop0: detected capacity change from 0 to 64
=====================================================
BUG: KMSAN: uninit-value in __hfs_ext_read_extent fs/hfs/extent.c:160 [inline]
BUG: KMSAN: uninit-value in hfs_free_fork+0x6b4/0xa50 fs/hfs/extent.c:320
 __hfs_ext_read_extent fs/hfs/extent.c:160 [inline]
 hfs_free_fork+0x6b4/0xa50 fs/hfs/extent.c:320
 hfs_cat_delete+0x501/0xb90 fs/hfs/catalog.c:247
 hfs_remove+0x16a/0x2f0 fs/hfs/dir.c:262
 vfs_unlink+0x676/0xa90 fs/namei.c:4469
 do_unlinkat+0x823/0xe10 fs/namei.c:4533
 __do_sys_unlink fs/namei.c:4581 [inline]
 __se_sys_unlink fs/namei.c:4579 [inline]
 __x64_sys_unlink+0x76/0xa0 fs/namei.c:4579
 x64_sys_call+0x30d3/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4091 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 __do_kmalloc_node mm/slub.c:4263 [inline]
 __kmalloc_noprof+0x661/0xf30 mm/slub.c:4276
 kmalloc_noprof include/linux/slab.h:882 [inline]
 hfs_find_init+0x91/0x250 fs/hfs/bfind.c:21
 hfs_free_fork+0x3bb/0xa50 fs/hfs/extent.c:316
 hfs_cat_delete+0x501/0xb90 fs/hfs/catalog.c:247
 hfs_remove+0x16a/0x2f0 fs/hfs/dir.c:262
 vfs_unlink+0x676/0xa90 fs/namei.c:4469
 do_unlinkat+0x823/0xe10 fs/namei.c:4533
 __do_sys_unlink fs/namei.c:4581 [inline]
 __se_sys_unlink fs/namei.c:4579 [inline]
 __x64_sys_unlink+0x76/0xa0 fs/namei.c:4579
 x64_sys_call+0x30d3/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 6013 Comm: syz.0.15 Not tainted 6.12.0-rc7-syzkaller-g2d5404caa8c7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
=====================================================


Tested on:

commit:         2d5404ca Linux 6.12-rc7
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12cd38c0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d1e659028faecb9
dashboard link: https://syzkaller.appspot.com/bug?extid=2e6fb1f89ce5e13cd02d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.

Re: [syzbot] [hfs?] KMSAN: uninit-value in hfs_free_fork

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

failed to apply patch:
checking file fs/hfs/bfind.c
patch: **** unexpected end of file in patch



Tested on:

commit:         2d5404ca Linux 6.12-rc7
git tree:       upstream
kernel config:  https://syzkaller.appspot.com/x/.config?x=522060455c43d52e
dashboard link: https://syzkaller.appspot.com/bug?extid=2e6fb1f89ce5e13cd02d
compiler:       
patch:          https://syzkaller.appspot.com/x/patch.diff?x=14cfb4e8580000

Re: [syzbot] [hfs?] KMSAN: uninit-value in hfs_free_fork

[syzbot]

Hello,

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

Reported-by: syzbot+2e6fb1f89ce5e13cd02d@syzkaller.appspotmail.com
Tested-by: syzbot+2e6fb1f89ce5e13cd02d@syzkaller.appspotmail.com

Tested on:

commit:         2d5404ca Linux 6.12-rc7
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=136874e8580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d1e659028faecb9
dashboard link: https://syzkaller.appspot.com/bug?extid=2e6fb1f89ce5e13cd02d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1739bea7980000

Note: testing is done by a robot and is best-effort only.