Ext4Pkg: Fix division by zero by adding check for s_inodes_per_group

Superblock s_inodes_per_group field can't be zero, it leads to division by zero in BlockGroup routine Ext4ReadInode Cc: Marvin Häuser <[email protected]> Cc: Pedro Falcato <[email protected]> Cc: Vitaly Cheptsov <[email protected]> Fixes: d9ceedc ("Ext4Pkg: Add Ext4Dxe driver.") Signed-off-by: Savva Mitrofanov <[email protected]> Reviewed-by: Pedro Falcato <[email protected]> Reviewed-by: Marvin Häuser <[email protected]>
tianocore · Feb 8, 2023 · d99e159 · d99e159
1 parent 0bea20a
commit d99e159
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/Features/Ext4Pkg/Ext4Dxe/Superblock.c b/Features/Ext4Pkg/Ext4Dxe/Superblock.c
@@ -243,6 +243,11 @@ Ext4OpenSuperblock (
 
   DEBUG ((DEBUG_FS, "Read only = %u\n", Partition->ReadOnly));
 
+  if (Sb->s_inodes_per_group == 0) {
+    DEBUG ((DEBUG_ERROR, "[ext4] Inodes per group can not be zero\n"));
+    return EFI_VOLUME_CORRUPTED;
+  }
+
   Partition->BlockSize = (UINT32)LShiftU64 (1024, Sb->s_log_block_size);
 
   // The size of a block group can also be calculated as 8 * Partition->BlockSize