diff options
| author | Randy Dunlap <rdunlap@infradead.org> | 2022-05-12 20:38:37 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-05-12 20:38:37 -0700 |
| commit | a3b774342fa752a5290c0de36375289dfcf4a260 (patch) | |
| tree | f48108dace8ad58195207d2f8b5242127ce69657 /fs/ntfs3 | |
| parent | cd290a9839cee2f6641558877e707bd373c8f6f1 (diff) | |
| download | linux-a3b774342fa752a5290c0de36375289dfcf4a260.tar.bz2 | |
fs/ntfs3: validate BOOT sectors_per_clusters
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>
Diffstat (limited to 'fs/ntfs3')
| -rw-r--r-- | fs/ntfs3/super.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c index 278dcf502410..b2b54c4553f9 100644 --- a/fs/ntfs3/super.c +++ b/fs/ntfs3/super.c @@ -668,9 +668,11 @@ static u32 format_size_gb(const u64 bytes, u32 *mb) static u32 true_sectors_per_clst(const struct NTFS_BOOT *boot) { - return boot->sectors_per_clusters <= 0x80 - ? boot->sectors_per_clusters - : (1u << (0 - boot->sectors_per_clusters)); + if (boot->sectors_per_clusters <= 0x80) + return boot->sectors_per_clusters; + if (boot->sectors_per_clusters >= 0xf4) /* limit shift to 2MB max */ + return 1U << (0 - boot->sectors_per_clusters); + return -EINVAL; } /* @@ -713,6 +715,8 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size, /* cluster size: 512, 1K, 2K, 4K, ... 2M */ sct_per_clst = true_sectors_per_clst(boot); + if ((int)sct_per_clst < 0) + goto out; if (!is_power_of_2(sct_per_clst)) goto out; |