fs/ext4: fix calling put_ext4 with truncated offset

Curently, we are using 32 bit multiplication to calculate the offset,
so the result will always be 32 bit.
This can silently cause file system corruption when performing a write
operation on partition larger than 4 GiB.

This patch address the issue by simply promoting the terms to 64 bit,
and let compilers decide how to do the multiplication efficiently.

Signed-off-by: Ma Haijun <mahaijuns@gmail.com>

1 files changed, 17 insertions, 17 deletions

diff --git a/fs/ext4/ext4_common.c b/fs/ext4/ext4_common.c
index 352943e..cff50d8 100644
--- a/fs/ext4/ext4_common.c
+++ b/fs/ext4/ext4_common.c
@@ -445,9 +445,9 @@ restart:
 					goto fail;
 				}
 				put_ext4(((uint64_t)
-					  (g_parent_inode->b.
+					  ((uint64_t)g_parent_inode->b.
 					   blocks.dir_blocks[direct_blk_idx] *
-					   fs->blksz)), zero_buffer, fs->blksz);
+					   (uint64_t)fs->blksz)), zero_buffer, fs->blksz);
 				g_parent_inode->size =
 				    g_parent_inode->size + fs->blksz;
 				g_parent_inode->blockcnt =
@@ -864,8 +864,8 @@ long int ext4fs_get_new_blk_no(void)
 		for (i = 0; i < fs->no_blkgrp; i++) {
 			if (bgd[i].free_blocks) {
 				if (bgd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) {
-					put_ext4(((uint64_t) (bgd[i].block_id *
-							      fs->blksz)),
+					put_ext4(((uint64_t) ((uint64_t)bgd[i].block_id *
+							      (uint64_t)fs->blksz)),
 						 zero_buffer, fs->blksz);
 					bgd[i].bg_flags =
 					    bgd[i].
@@ -929,8 +929,8 @@ restart:
 
 		if (bgd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) {
 			memset(zero_buffer, '\0', fs->blksz);
-			put_ext4(((uint64_t) (bgd[bg_idx].block_id *
-					fs->blksz)), zero_buffer, fs->blksz);
+			put_ext4(((uint64_t) ((uint64_t)bgd[bg_idx].block_id *
+					(uint64_t)fs->blksz)), zero_buffer, fs->blksz);
 			memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
 			bgd[bg_idx].bg_flags = bgd[bg_idx].bg_flags &
 						~EXT4_BG_BLOCK_UNINIT;
@@ -996,8 +996,8 @@ int ext4fs_get_new_inode_no(void)
 						bgd[i].free_inodes;
 				if (bgd[i].bg_flags & EXT4_BG_INODE_UNINIT) {
 					put_ext4(((uint64_t)
-						  (bgd[i].inode_id *
-							fs->blksz)),
+						  ((uint64_t)bgd[i].inode_id *
+							(uint64_t)fs->blksz)),
 						 zero_buffer, fs->blksz);
 					bgd[i].bg_flags = bgd[i].bg_flags &
 							~EXT4_BG_INODE_UNINIT;
@@ -1037,8 +1037,8 @@ restart:
 		ibmap_idx = fs->curr_inode_no / inodes_per_grp;
 		if (bgd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) {
 			memset(zero_buffer, '\0', fs->blksz);
-			put_ext4(((uint64_t) (bgd[ibmap_idx].inode_id *
-					      fs->blksz)), zero_buffer,
+			put_ext4(((uint64_t) ((uint64_t)bgd[ibmap_idx].inode_id *
+					      (uint64_t)fs->blksz)), zero_buffer,
 				 fs->blksz);
 			bgd[ibmap_idx].bg_flags =
 			    bgd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT;
@@ -1143,7 +1143,7 @@ static void alloc_single_indirect_block(struct ext2_inode *file_inode,
 		}
 
 		/* write the block to disk */
-		put_ext4(((uint64_t) (si_blockno * fs->blksz)),
+		put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
 			 si_start_addr, fs->blksz);
 		file_inode->b.blocks.indir_block = si_blockno;
 	}
@@ -1242,7 +1242,7 @@ static void alloc_double_indirect_block(struct ext2_inode *file_inode,
 					break;
 			}
 			/* write the block  table */
-			put_ext4(((uint64_t) (di_blockno_child * fs->blksz)),
+			put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
 				 di_child_buff_start, fs->blksz);
 			free(di_child_buff_start);
 			di_child_buff_start = NULL;
@@ -1250,7 +1250,7 @@ static void alloc_double_indirect_block(struct ext2_inode *file_inode,
 			if (*total_remaining_blocks == 0)
 				break;
 		}
-		put_ext4(((uint64_t) (di_blockno_parent * fs->blksz)),
+		put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
 			 di_block_start_addr, fs->blksz);
 		file_inode->b.blocks.double_indir_block = di_blockno_parent;
 	}
@@ -1348,8 +1348,8 @@ static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
 						break;
 				}
 				/* write the child block */
-				put_ext4(((uint64_t) (ti_child_blockno *
-						      fs->blksz)),
+				put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
+						      (uint64_t)fs->blksz)),
 					 ti_cbuff_start_addr, fs->blksz);
 				free(ti_cbuff_start_addr);
 
@@ -1357,7 +1357,7 @@ static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
 					break;
 			}
 			/* write the parent block */
-			put_ext4(((uint64_t) (ti_parent_blockno * fs->blksz)),
+			put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
 				 ti_pbuff_start_addr, fs->blksz);
 			free(ti_pbuff_start_addr);
 
@@ -1365,7 +1365,7 @@ static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
 				break;
 		}
 		/* write the grand parent block */
-		put_ext4(((uint64_t) (ti_gp_blockno * fs->blksz)),
+		put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
 			 ti_gp_buff_start_addr, fs->blksz);
 		file_inode->b.blocks.triple_indir_block = ti_gp_blockno;
 	}