btrfs-progs: Enhance chunk validation check

Enhance chunk validation:
1) Num_stripes
   We already have such check but it's only in super block sys chunk
   array.
   Now check all on-disk chunks.

2) Chunk logical
   It should be aligned to sector size.
   This behavior should be *DOUBLE CHECKED* for 64K sector size like
   PPC64 or AArch64.
   Maybe we can found some hidden bugs.

3) Chunk length
   Same as chunk logical, should be aligned to sector size.

4) Stripe length
   It should be power of 2.

5) Chunk type
   Any bit out of TYPE_MAS | PROFILE_MASK is invalid.

With all these much restrict rules, several fuzzed image reported in
mail list should no longer cause btrfsck error.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/kerncompat.h b/kerncompat.h
index 7c627ba..0f207b7 100644
--- a/kerncompat.h
+++ b/kerncompat.h
@@ -310,6 +310,14 @@ static inline long IS_ERR(const void *ptr)
 #define __bitwise
 #endif
 
+/* Alignment check */
+#define IS_ALIGNED(x, a)                (((x) & ((typeof(x))(a) - 1)) == 0)
+
+static inline int is_power_of_2(unsigned long n)
+{
+	return (n != 0 && ((n & (n - 1)) == 0));
+}
+
 typedef u16 __bitwise __le16;
 typedef u16 __bitwise __be16;
 typedef u32 __bitwise __le32;