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

btrfs: fix information leak in btrfs_ioctl_logical_to_ino()

Syzbot reported the following information leak for in
btrfs_ioctl_logical_to_ino():

  BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
  BUG: KMSAN: kernel-infoleak in _copy_to_user+0xbc/0x110 lib/usercopy.c:40
   instrument_copy_to_user include/linux/instrumented.h:114 [inline]
   _copy_to_user+0xbc/0x110 lib/usercopy.c:40
   copy_to_user include/linux/uaccess.h:191 [inline]
   btrfs_ioctl_logical_to_ino+0x440/0x750 fs/btrfs/ioctl.c:3499
   btrfs_ioctl+0x714/0x1260
   vfs_ioctl fs/ioctl.c:51 [inline]
   __do_sys_ioctl fs/ioctl.c:904 [inline]
   __se_sys_ioctl+0x261/0x450 fs/ioctl.c:890
   __x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:890
   x64_sys_call+0x1883/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:17
   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:
   __kmalloc_large_node+0x231/0x370 mm/slub.c:3921
   __do_kmalloc_node mm/slub.c:3954 [inline]
   __kmalloc_node+0xb07/0x1060 mm/slub.c:3973
   kmalloc_node include/linux/slab.h:648 [inline]
   kvmalloc_node+0xc0/0x2d0 mm/util.c:634
   kvmalloc include/linux/slab.h:766 [inline]
   init_data_container+0x49/0x1e0 fs/btrfs/backref.c:2779
   btrfs_ioctl_logical_to_ino+0x17c/0x750 fs/btrfs/ioctl.c:3480
   btrfs_ioctl+0x714/0x1260
   vfs_ioctl fs/ioctl.c:51 [inline]
   __do_sys_ioctl fs/ioctl.c:904 [inline]
   __se_sys_ioctl+0x261/0x450 fs/ioctl.c:890
   __x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:890
   x64_sys_call+0x1883/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:17
   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

  Bytes 40-65535 of 65536 are uninitialized
  Memory access of size 65536 starts at ffff888045a40000

This happens, because we're copying a 'struct btrfs_data_container' back
to user-space. This btrfs_data_container is allocated in
'init_data_container()' via kvmalloc(), which does not zero-fill the
memory.

Fix this by using kvzalloc() which zeroes out the memory on allocation.

kernel.org https://git.kernel.org/stable/c/2f7ef5bb4a2f3e481ef05fab946edb97c84f67cf [No types assigned]

kernel.org https://git.kernel.org/stable/c/30189e54ba80e3209d34cfeea87b848f6ae025e6 [No types assigned]

kernel.org https://git.kernel.org/stable/c/3a63cee1a5e14a3e52c19142c61dd5fcb524f6dc [No types assigned]

kernel.org https://git.kernel.org/stable/c/689efe22e9b5b7d9d523119a9a5c3c17107a0772 [No types assigned]

kernel.org https://git.kernel.org/stable/c/73db209dcd4ae026021234d40cfcb2fb5b564b86 [No types assigned]

kernel.org https://git.kernel.org/stable/c/8bdbcfaf3eac42f98e5486b3d7e130fa287811f6 [No types assigned]

kernel.org https://git.kernel.org/stable/c/e58047553a4e859dafc8d1d901e1de77c9dd922d [No types assigned]

kernel.org https://git.kernel.org/stable/c/fddc19631c51d9c17d43e9f822a7bc403af88d54 [No types assigned]