fs/ntfs3: Fix alternative boot searching

[ Upstream commit dcc852e509a4cba0ac6ac734077cef260e4e0fe6 ]

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c
index bcb17a1723465c95e1dc709a59898fdb9ff529cf..9124d74ea676be2c0c17a712620edb1b9013eab5 100644 (file)
--- a/fs/ntfs3/super.c
+++ b/fs/ntfs3/super.c
@@ -838,7 +838,7 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
        struct ntfs_sb_info *sbi = sb->s_fs_info;
        int err;
        u32 mb, gb, boot_sector_size, sct_per_clst, record_size;
-       u64 sectors, clusters, mlcn, mlcn2;
+       u64 sectors, clusters, mlcn, mlcn2, dev_size0;
        struct NTFS_BOOT *boot;
        struct buffer_head *bh;
        struct MFT_REC *rec;
@@ -847,6 +847,9 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
        u32 boot_off = 0;
        const char *hint = "Primary boot";
 
+       /* Save original dev_size. Used with alternative boot. */
+       dev_size0 = dev_size;
+
        sbi->volume.blocks = dev_size >> PAGE_SHIFT;
 
        bh = ntfs_bread(sb, 0);
@@ -1084,9 +1087,9 @@ check_boot:
        }
 
 out:
-       if (err == -EINVAL && !bh->b_blocknr && dev_size > PAGE_SHIFT) {
+       if (err == -EINVAL && !bh->b_blocknr && dev_size0 > PAGE_SHIFT) {
                u32 block_size = min_t(u32, sector_size, PAGE_SIZE);
-               u64 lbo = dev_size - sizeof(*boot);
+               u64 lbo = dev_size0 - sizeof(*boot);
 
                /*
                 * Try alternative boot (last sector)
@@ -1100,6 +1103,7 @@ out:
 
                boot_off = lbo & (block_size - 1);
                hint = "Alternative boot";
+               dev_size = dev_size0; /* restore original size. */
                goto check_boot;
        }
        brelse(bh);