iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

md: Fix types in sb writer

Browse Source 
Page->index is a pgoff_t and multiplying could cause overflows on a
32-bit architecture. In the sb writer, this is used to calculate and
verify the sector being used, and is multiplied by a sector value. Using
sector_t will cast it to a u64 type and is the more appropriate type for
the unit. Additionally, the integer size unit is converted to a sector
unit in later calculations, and is now corrected to be an unsigned type.

Finally, clean up the calculations using variable aliases to improve
readabiliy.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jon Derrick <jonathan.derrick@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230224183323.638-3-jonathan.derrick@linux.dev
This commit is contained in:
Jon Derrick 2023-02-24 11:33:22 -07:00 committed by Song Liu
parent 328e17d8d9
commit 10172f200b
1 changed files with 14 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
drivers/md/md-bitmap.c
View File

@ -215,12 +215,13 @@ static int __write_sb_page(struct md_rdev *rdev, struct bitmap *bitmap,
struct block_device *bdev;
struct mddev *mddev = bitmap->mddev;
struct bitmap_storage *store = &bitmap->storage;
loff_t offset = mddev->bitmap_info.offset;
int size = PAGE_SIZE;
sector_t offset = mddev->bitmap_info.offset;
sector_t ps, sboff, doff;
unsigned int size = PAGE_SIZE;
bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev;
if (page->index == store->file_pages - 1) {
int last_page_size = store->bytes & (PAGE_SIZE - 1);
unsigned int last_page_size = store->bytes & (PAGE_SIZE - 1);
if (last_page_size == 0)
last_page_size = PAGE_SIZE;
@ -228,43 +229,35 @@ static int __write_sb_page(struct md_rdev *rdev, struct bitmap *bitmap,
bdev_logical_block_size(bdev));
}
ps = page->index * PAGE_SIZE / SECTOR_SIZE;
sboff = rdev->sb_start + offset;
doff = rdev->data_offset;
/* Just make sure we aren't corrupting data or metadata */
if (mddev->external) {
/* Bitmap could be anywhere. */
if (rdev->sb_start + offset
+ (page->index * (PAGE_SIZE / SECTOR_SIZE))
> rdev->data_offset &&
rdev->sb_start + offset
< (rdev->data_offset + mddev->dev_sectors
+ (PAGE_SIZE / SECTOR_SIZE)))
if (sboff + ps > doff &&
sboff < (doff + mddev->dev_sectors + PAGE_SIZE / SECTOR_SIZE))
return -EINVAL;
} else if (offset < 0) {
/* DATA BITMAP METADATA */
if (offset
+ (long)(page->index * (PAGE_SIZE / SECTOR_SIZE))
+ size / SECTOR_SIZE > 0)
if (offset + ps + size / SECTOR_SIZE > 0)
/* bitmap runs in to metadata */
return -EINVAL;
if (rdev->data_offset + mddev->dev_sectors
> rdev->sb_start + offset)
if (doff + mddev->dev_sectors > sboff)
/* data runs in to bitmap */
return -EINVAL;
} else if (rdev->sb_start < rdev->data_offset) {
/* METADATA BITMAP DATA */
if (rdev->sb_start + offset
+ page->index * (PAGE_SIZE / SECTOR_SIZE)
+ size / SECTOR_SIZE > rdev->data_offset)
if (sboff + ps + size / SECTOR_SIZE > doff)
/* bitmap runs in to data */
return -EINVAL;
} else {
/* DATA METADATA BITMAP - no problems */
}
md_super_write(mddev, rdev,
rdev->sb_start + offset
+ page->index * (PAGE_SIZE / SECTOR_SIZE),
size, page);
md_super_write(mddev, rdev, sboff + ps, (int) size, page);
return 0;
}