[PATCH AUTOSEL 6.5 08/52] fs/ntfs3: Fix alternative boot searching

Sasha Levin
2023-10-29T22:54:56Z

[ Upstream commit dcc852e509a4cba0ac6ac734077cef260e4e0fe6 ]

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/ntfs3/super.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c
index 18a8bc73b8e2d..98545060580ac 100644
--- 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);
@@ -1079,9 +1082,9 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
}

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)
@@ -1095,6 +1098,7 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,

boot_off = lbo & (block_size - 1);
hint = "Alternative boot";
+ dev_size = dev_size0; /* restore original size. */
goto check_boot;
}
brelse(bh);
--
2.42.0