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

hfs: fix to initialize fields of hfsinodeinfo after hfsallocinode()

Syzbot reports uninitialized value access issue as below:

loop0: detected capacity change from 0 to 64

BUG: KMSAN: uninit-value in hfsrevalidatedentry+0x307/0x3f0 fs/hfs/sysdep.c:30 hfsrevalidatedentry+0x307/0x3f0 fs/hfs/sysdep.c:30 drevalidate fs/namei.c:862 [inline] lookupfast+0x89e/0x8e0 fs/namei.c:1649 walkcomponent fs/namei.c:2001 [inline] linkpathwalk+0x817/0x1480 fs/namei.c:2332 pathlookupat+0xd9/0x6f0 fs/namei.c:2485 filenamelookup+0x22e/0x740 fs/namei.c:2515 userpathatempty+0x8b/0x390 fs/namei.c:2924 userpathat include/linux/namei.h:57 [inline] domount fs/namespace.c:3689 [inline] _dosysmount fs/namespace.c:3898 [inline] _sesysmount+0x66b/0x810 fs/namespace.c:3875 _x64sysmount+0xe4/0x140 fs/namespace.c:3875 dosyscallx64 arch/x86/entry/common.c:52 [inline] dosyscall64+0xcf/0x1e0 arch/x86/entry/common.c:83 entrySYSCALL64afterhwframe+0x63/0x6b

BUG: KMSAN: uninit-value in hfsextreadextent fs/hfs/extent.c:196 [inline] BUG: KMSAN: uninit-value in hfsgetblock+0x92d/0x1620 fs/hfs/extent.c:366 hfsextreadextent fs/hfs/extent.c:196 [inline] hfsgetblock+0x92d/0x1620 fs/hfs/extent.c:366 blockreadfullfolio+0x4ff/0x11b0 fs/buffer.c:2271 hfsreadfolio+0x55/0x60 fs/hfs/inode.c:39 filemapreadfolio+0x148/0x4f0 mm/filemap.c:2426 doreadcachefolio+0x7c8/0xd90 mm/filemap.c:3553 doreadcachepage mm/filemap.c:3595 [inline] readcachepage+0xfb/0x2f0 mm/filemap.c:3604 readmappingpage include/linux/pagemap.h:755 [inline] hfsbtreeopen+0x928/0x1ae0 fs/hfs/btree.c:78 hfsmdbget+0x260c/0x3000 fs/hfs/mdb.c:204 hfsfillsuper+0x1fb1/0x2790 fs/hfs/super.c:406 mountbdev+0x628/0x920 fs/super.c:1359 hfsmount+0xcd/0xe0 fs/hfs/super.c:456 legacygettree+0x167/0x2e0 fs/fscontext.c:610 vfsgettree+0xdc/0x5d0 fs/super.c:1489 donewmount+0x7a9/0x16f0 fs/namespace.c:3145 pathmount+0xf98/0x26a0 fs/namespace.c:3475 domount fs/namespace.c:3488 [inline] _dosysmount fs/namespace.c:3697 [inline] _sesysmount+0x919/0x9e0 fs/namespace.c:3674 _ia32sysmount+0x15b/0x1b0 fs/namespace.c:3674 dosyscall32irqson arch/x86/entry/common.c:112 [inline] _dofastsyscall32+0xa2/0x100 arch/x86/entry/common.c:178 dofastsyscall32+0x37/0x80 arch/x86/entry/common.c:203 doSYSENTER32+0x1f/0x30 arch/x86/entry/common.c:246 entrySYSENTERcompatafterhwframe+0x70/0x82

Uninit was created at: allocpages+0x9a6/0xe00 mm/pagealloc.c:4590 _allocpagesnode include/linux/gfp.h:238 [inline] allocpagesnode include/linux/gfp.h:261 [inline] allocslabpage mm/slub.c:2190 [inline] allocateslab mm/slub.c:2354 [inline] newslab+0x2d7/0x1400 mm/slub.c:2407 _slaballoc+0x16b5/0x3970 mm/slub.c:3540 _slaballoc mm/slub.c:3625 [inline] _slaballocnode mm/slub.c:3678 [inline] slaballocnode mm/slub.c:3850 [inline] kmemcachealloclru+0x64d/0xb30 mm/slub.c:3879 allocinodesb include/linux/fs.h:3018 [inline] hfsallocinode+0x5a/0xc0 fs/hfs/super.c:165 allocinode+0x83/0x440 fs/inode.c:260 newinodepseudo fs/inode.c:1005 [inline] newinode+0x38/0x4f0 fs/inode.c:1031 hfsnewinode+0x61/0x1010 fs/hfs/inode.c:186 hfsmkdir+0x54/0x250 fs/hfs/dir.c:228 vfsmkdir+0x49a/0x700 fs/namei.c:4126 domkdirat+0x529/0x810 fs/namei.c:4149 _dosysmkdirat fs/namei.c:4164 [inline] _sesysmkdirat fs/namei.c:4162 [inline] _x64sysmkdirat+0xc8/0x120 fs/namei.c:4162 dosyscallx64 arch/x86/entry/common.c:52 [inline] dosyscall64+0xcf/0x1e0 arch/x86/entry/common.c:83 entrySYSCALL64afterhwframe+0x63/0x6b

It missed to initialize .tzsecondswest, .cachedstart and .cachedblocks fields in struct hfsinodeinfo after hfsalloc_inode(), fix it.