Hi Linus,
I split up my previous patch into two. Hopefully this is more
acceptable for you or will trigger some comments.
This is the first part:
1) shmem_remount_fs garbles parameters which are not supplied
2) shmem_truncate should check the maximum size else we get ugly
oopses
3) shmem_file_setup should give an error if the size is too big. So
the application will fail early. I also cleaned up the error
handling a bit.
4) We should recalculate the inode on page allocation. Else we get
really weird sizes on sparse files.
Please apply
Christoph
diff -uNr 6-pre8/mm/shmem.c 6-pre8-fix1/mm/shmem.c
--- 6-pre8/mm/shmem.c Tue Jun 12 09:49:28 2001
+++ 6-pre8-fix1/mm/shmem.c Tue Jul 3 08:55:20 2001
@@ -3,7 +3,8 @@
*
* Copyright (C) 2000 Linus Torvalds.
* 2000 Transmeta Corp.
- * 2000 Christoph Rohland
+ * 2000-2001 Christoph Rohland
+ * 2000-2001 SAP AG
*
* This file is released under the GPL.
*/
@@ -33,7 +34,7 @@
#define TMPFS_MAGIC 0x01021994
#define ENTRIES_PER_PAGE (PAGE_SIZE/sizeof(unsigned long))
-#define NR_SINGLE (ENTRIES_PER_PAGE + SHMEM_NR_DIRECT)
+#define SHMEM_MAX_BLOCKS (SHMEM_NR_DIRECT + ENTRIES_PER_PAGE*ENTRIES_PER_PAGE)
static struct super_operations shmem_ops;
static struct address_space_operations shmem_aops;
@@ -193,7 +194,14 @@
}
out:
- info->max_index = index;
+ /*
+ * We have no chance to give an error, so we limit it to max
+ * size here and the application will fail later
+ */
+ if (index > SHMEM_MAX_BLOCKS)
+ info->max_index = SHMEM_MAX_BLOCKS;
+ else
+ info->max_index = index;
info->swapped -= freed;
shmem_recalc_inode(inode);
spin_unlock (&info->lock);
@@ -314,6 +322,7 @@
return page;
}
+ shmem_recalc_inode(inode);
if (entry->val) {
unsigned long flags;
@@ -1027,6 +1036,8 @@
unsigned long max_inodes, inodes;
struct shmem_sb_info *info = &sb->u.shmem_sb;
+ max_blocks = info->max_blocks;
+ max_inodes = info->max_inodes;
if (shmem_parse_options (data, NULL, &max_blocks, &max_inodes))
return -EINVAL;
@@ -1074,7 +1085,7 @@
sb->u.shmem_sb.free_blocks = blocks;
sb->u.shmem_sb.max_inodes = inodes;
sb->u.shmem_sb.free_inodes = inodes;
- sb->s_maxbytes = (unsigned long long)(SHMEM_NR_DIRECT + (ENTRIES_PER_PAGE*ENTRIES_PER_PAGE)) << PAGE_CACHE_SHIFT;
+ sb->s_maxbytes = (unsigned long long)SHMEM_MAX_BLOCKS << PAGE_CACHE_SHIFT;
sb->s_blocksize = PAGE_CACHE_SIZE;
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
sb->s_magic = TMPFS_MAGIC;
@@ -1282,9 +1293,11 @@
struct qstr this;
int vm_enough_memory(long pages);
- error = -ENOMEM;
+ if (size > (unsigned long long) SHMEM_MAX_BLOCKS << PAGE_CACHE_SHIFT)
+ return ERR_PTR(-EINVAL);
+
if (!vm_enough_memory((size) >> PAGE_SHIFT))
- goto out;
+ return ERR_PTR(-ENOMEM);
this.name = name;
this.len = strlen(name);
@@ -1292,7 +1305,7 @@
root = tmpfs_fs_type.kern_mnt->mnt_root;
dentry = d_alloc(root, &this);
if (!dentry)
- goto out;
+ return ERR_PTR(-ENOMEM);
error = -ENFILE;
file = get_empty_filp();
@@ -1318,7 +1331,6 @@
put_filp(file);
put_dentry:
dput (dentry);
-out:
return ERR_PTR(error);
}
/*
-
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This archive was generated by hypermail 2b29 : Sat Jul 07 2001 - 21:00:11 EST