On a FS with a rather large blockize (> 4K), the old block map
structure can construct a fat enough "tree" (or whatever we call that
lopsided thing) that (at least in theory) one could create mappings
for logical blocks higher than 32 bits. In practice this doesn't
happen, but the 'max' and 'iter' variables that the punch helpers use
will overflow because the BLOCK_SIZE_BITS shifts are too large to fit
a 32-bit variable. This causes punch to fail on TIND-mapped blocks
even if the file is < 16T. So enlarge the fields to fit.
(Yes this is an obscure corner case...)
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
lib/ext2fs/punch.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
diff --git a/lib/ext2fs/punch.c b/lib/ext2fs/punch.c
index 4471f46..790a0ad8 100644
--- a/lib/ext2fs/punch.c
+++ b/lib/ext2fs/punch.c
@@ -50,15 +50,16 @@ static errcode_t ind_punch(ext2_filsys fs, struct ext2_inode *inode,
blk_t start, blk_t count, int max)
{
errcode_t retval;
- blk_t b, offset;
- int i, incr;
+ blk_t b;
+ int i;
+ blk64_t offset, incr;
int freed = 0;
#ifdef PUNCH_DEBUG
printf("Entering ind_punch, level %d, start %u, count %u, "
"max %d\n", level, start, count, max);
#endif
- incr = 1 << ((EXT2_BLOCK_SIZE_BITS(fs->super)-2)*level);
+ incr = 1ULL << ((EXT2_BLOCK_SIZE_BITS(fs->super)-2)*level);
for (i=0, offset=0; i < max; i++, p++, offset += incr) {
if (offset >= start + count)
break;
@@ -87,7 +88,7 @@ static errcode_t ind_punch(ext2_filsys fs, struct ext2_inode *inode,
continue;
}
#ifdef PUNCH_DEBUG
- printf("Freeing block %u (offset %d)\n", b, offset);
+ printf("Freeing block %u (offset %llu)\n", b, offset);
#endif
ext2fs_block_alloc_stats(fs, b, -1);
*p = 0;
@@ -108,7 +109,7 @@ static errcode_t ext2fs_punch_ind(ext2_filsys fs, struct ext2_inode *inode,
int num = EXT2_NDIR_BLOCKS;
blk_t *bp = inode->i_block;
blk_t addr_per_block;
- blk_t max = EXT2_NDIR_BLOCKS;
+ blk64_t max = EXT2_NDIR_BLOCKS;
if (!block_buf) {
retval = ext2fs_get_array(3, fs->blocksize, &buf);
@@ -119,10 +120,10 @@ static errcode_t ext2fs_punch_ind(ext2_filsys fs, struct ext2_inode *inode,
addr_per_block = (blk_t) fs->blocksize >> 2;
- for (level=0; level < 4; level++, max *= addr_per_block) {
+ for (level = 0; level < 4; level++, max *= (blk64_t)addr_per_block) {
#ifdef PUNCH_DEBUG
printf("Main loop level %d, start %u count %u "
- "max %d num %d\n", level, start, count, max, num);
+ "max %llu num %d\n", level, start, count, max, num);
#endif
if (start < max) {
retval = ind_punch(fs, inode, block_buf, bp, level,
--
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