BACKPORT: f2fs: sanity check log_blocks_per_seg

f2fs currently only supports 4KB block size and 2MB segment size.
Sanity check log_blocks_per_seg == 9, i.e. 2MB/4KB = (1 << 9)

Partially
(cherry-picked from commit 9a59b62fd88196844cee5fff851bee2cfd7afb6e)

f2fs: do more integrity verification for superblock

Do more sanity check for superblock during ->mount.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Bug: 36817013
Change-Id: I0be52e54fba82083068337ceb9f7ad985a87319f
Signed-off-by: Jin Qian <jinqian@google.com>

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 3a65e013235283e2b0fd1f8e6afe6790b0af41a6..98a77b0a365d9f73afdae9d736e514b9d566c8e2 100644 (file)
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -947,6 +947,14 @@ static int sanity_check_raw_super(struct super_block *sb,
                return 1;
        }
 
+       /* check log blocks per segment */
+       if (le32_to_cpu(raw_super->log_blocks_per_seg) != 9) {
+               f2fs_msg(sb, KERN_INFO,
+                       "Invalid log blocks per segment (%u)\n",
+                       le32_to_cpu(raw_super->log_blocks_per_seg));
+               return 1;
+       }
+
        /* Currently, support 512/1024/2048/4096 bytes sector size */
        if (le32_to_cpu(raw_super->log_sectorsize) >
                                F2FS_MAX_LOG_SECTOR_SIZE ||