fs/ntfs3: validate BOOT sectors_per_clusters
authorRandy Dunlap <rdunlap@infradead.org>
Fri, 13 May 2022 03:38:37 +0000 (20:38 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 6 Jun 2022 06:43:40 +0000 (08:43 +0200)
commit58cf68a1886d14ffdc5c892ce483a82156769e88
tree8fc56b4986e4c087ad3ce1abeae1577b59b475fe
parent6e5bc6f7fef0f3e725b801a510b205ebc6f245d8
fs/ntfs3: validate BOOT sectors_per_clusters

commit a3b774342fa752a5290c0de36375289dfcf4a260 upstream.

When the NTFS BOOT sectors_per_clusters field is > 0x80, it represents a
shift value.  Make sure that the shift value is not too large before using
it (NTFS max cluster size is 2MB).  Return -EVINVAL if it too large.

This prevents negative shift values and shift values that are larger than
the field size.

Prevents this UBSAN error:

 UBSAN: shift-out-of-bounds in ../fs/ntfs3/super.c:673:16
 shift exponent -192 is negative

Link: https://lkml.kernel.org/r/20220502175342.20296-1-rdunlap@infradead.org
Fixes: 82cae269cfa9 ("fs/ntfs3: Add initialization of super block")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: syzbot+1631f09646bc214d2e76@syzkaller.appspotmail.com
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Kari Argillander <kari.argillander@stargateuniverse.net>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/ntfs3/super.c