f2fs: sanity check segment count
F2FS uses 4 bytes to represent block address. As a result, supported
size of disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
Change-Id: I2605b8655c80858160c17e7f026db42bb0ec4bb2
Signed-off-by: Jin Qian <jinqian@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 7b5d7aa..29b8875 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1388,6 +1388,12 @@
le32_to_cpu(raw_super->root_ino));
return 1;
}
+ if (le32_to_cpu(raw_super->segment_count) > F2FS_MAX_SEGMENT) {
+ f2fs_msg(sb, KERN_INFO,
+ "Invalid segment count (%u)",
+ le32_to_cpu(raw_super->segment_count));
+ return 1;
+ }
/* check CP/SIT/NAT/SSA/MAIN_AREA area boundary */
if (sanity_check_area_boundary(sbi, bh))
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index 1a1d318..e020cbf 100644
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -289,6 +289,12 @@
#define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
/*
+ * F2FS uses 4 bytes to represent block address. As a result, supported size of
+ * disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
+ */
+#define F2FS_MAX_SEGMENT ((16 * 1024 * 1024) / 2)
+
+/*
* Note that f2fs_sit_entry->vblocks has the following bit-field information.
* [15:10] : allocation type such as CURSEG_XXXX_TYPE
* [9:0] : valid block count