Subject: CVE-2024-42311: hfs: fix to initialize fields of hfs_inode_info after hfs_alloc_inode()

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

hfs: fix to initialize fields of hfs_inode_info after hfs_alloc_inode()

Syzbot reports uninitialized value access issue as below:

loop0: detected capacity change from 0 to 64
=====================================================
BUG: KMSAN: uninit-value in hfs_revalidate_dentry+0x307/0x3f0 fs/hfs/sysdep.c:30
 hfs_revalidate_dentry+0x307/0x3f0 fs/hfs/sysdep.c:30
 d_revalidate fs/namei.c:862 [inline]
 lookup_fast+0x89e/0x8e0 fs/namei.c:1649
 walk_component fs/namei.c:2001 [inline]
 link_path_walk+0x817/0x1480 fs/namei.c:2332
 path_lookupat+0xd9/0x6f0 fs/namei.c:2485
 filename_lookup+0x22e/0x740 fs/namei.c:2515
 user_path_at_empty+0x8b/0x390 fs/namei.c:2924
 user_path_at include/linux/namei.h:57 [inline]
 do_mount fs/namespace.c:3689 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x66b/0x810 fs/namespace.c:3875
 __x64_sys_mount+0xe4/0x140 fs/namespace.c:3875
 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

BUG: KMSAN: uninit-value in hfs_ext_read_extent fs/hfs/extent.c:196 [inline]
BUG: KMSAN: uninit-value in hfs_get_block+0x92d/0x1620 fs/hfs/extent.c:366
 hfs_ext_read_extent fs/hfs/extent.c:196 [inline]
 hfs_get_block+0x92d/0x1620 fs/hfs/extent.c:366
 block_read_full_folio+0x4ff/0x11b0 fs/buffer.c:2271
 hfs_read_folio+0x55/0x60 fs/hfs/inode.c:39
 filemap_read_folio+0x148/0x4f0 mm/filemap.c:2426
 do_read_cache_folio+0x7c8/0xd90 mm/filemap.c:3553
 do_read_cache_page mm/filemap.c:3595 [inline]
 read_cache_page+0xfb/0x2f0 mm/filemap.c:3604
 read_mapping_page include/linux/pagemap.h:755 [inline]
 hfs_btree_open+0x928/0x1ae0 fs/hfs/btree.c:78
 hfs_mdb_get+0x260c/0x3000 fs/hfs/mdb.c:204
 hfs_fill_super+0x1fb1/0x2790 fs/hfs/super.c:406
 mount_bdev+0x628/0x920 fs/super.c:1359
 hfs_mount+0xcd/0xe0 fs/hfs/super.c:456
 legacy_get_tree+0x167/0x2e0 fs/fs_context.c:610
 vfs_get_tree+0xdc/0x5d0 fs/super.c:1489
 do_new_mount+0x7a9/0x16f0 fs/namespace.c:3145
 path_mount+0xf98/0x26a0 fs/namespace.c:3475
 do_mount fs/namespace.c:3488 [inline]
 __do_sys_mount fs/namespace.c:3697 [inline]
 __se_sys_mount+0x919/0x9e0 fs/namespace.c:3674
 __ia32_sys_mount+0x15b/0x1b0 fs/namespace.c:3674
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was created at:
 __alloc_pages+0x9a6/0xe00 mm/page_alloc.c:4590
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 alloc_slab_page mm/slub.c:2190 [inline]
 allocate_slab mm/slub.c:2354 [inline]
 new_slab+0x2d7/0x1400 mm/slub.c:2407
 ___slab_alloc+0x16b5/0x3970 mm/slub.c:3540
 __slab_alloc mm/slub.c:3625 [inline]
 __slab_alloc_node mm/slub.c:3678 [inline]
 slab_alloc_node mm/slub.c:3850 [inline]
 kmem_cache_alloc_lru+0x64d/0xb30 mm/slub.c:3879
 alloc_inode_sb include/linux/fs.h:3018 [inline]
 hfs_alloc_inode+0x5a/0xc0 fs/hfs/super.c:165
 alloc_inode+0x83/0x440 fs/inode.c:260
 new_inode_pseudo fs/inode.c:1005 [inline]
 new_inode+0x38/0x4f0 fs/inode.c:1031
 hfs_new_inode+0x61/0x1010 fs/hfs/inode.c:186
 hfs_mkdir+0x54/0x250 fs/hfs/dir.c:228
 vfs_mkdir+0x49a/0x700 fs/namei.c:4126
 do_mkdirat+0x529/0x810 fs/namei.c:4149
 __do_sys_mkdirat fs/namei.c:4164 [inline]
 __se_sys_mkdirat fs/namei.c:4162 [inline]
 __x64_sys_mkdirat+0xc8/0x120 fs/namei.c:4162
 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

It missed to initialize .tz_secondswest, .cached_start and .cached_blocks
fields in struct hfs_inode_info after hfs_alloc_inode(), fix it.

The Linux kernel CVE team has assigned CVE-2024-42311 to this issue.

Affected and fixed versions
===========================

	Fixed in 4.19.320 with commit f7316b2b2f11
	Fixed in 5.4.282 with commit 4a52861cd76e
	Fixed in 5.10.224 with commit 10f7163bfb5f
	Fixed in 5.15.165 with commit d55aae5c1730
	Fixed in 6.1.103 with commit 58d83fc16050
	Fixed in 6.6.44 with commit 9c4e40b9b731
	Fixed in 6.10.3 with commit d3493d6f0dfb
	Fixed in 6.11 with commit 26a2ed107929

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-42311
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	fs/hfs/inode.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/f7316b2b2f11cf0c6de917beee8d3de728be24db
	https://git.kernel.org/stable/c/4a52861cd76e79f1a593beb23d096523eb9732c2
	https://git.kernel.org/stable/c/10f7163bfb5f8b4e0c9c05a939f20b8540e33c65
	https://git.kernel.org/stable/c/d55aae5c1730d6b70d5d8eaff00113cd34772ea3
	https://git.kernel.org/stable/c/58d83fc160505a7009c39dec64effaac5129b971
	https://git.kernel.org/stable/c/9c4e40b9b731220f9464975e49da75496e3865c4
	https://git.kernel.org/stable/c/d3493d6f0dfb1ab5225b62faa77732983f2187a1
	https://git.kernel.org/stable/c/26a2ed107929a855155429b11e1293b83e6b2a8b