android_kernel_xiaomi_sm8350/fs/udf/ialloc.c
Eric Sandeen 225add6196 [PATCH] udf: initialize parts of inode earlier in create
I saw an oops down this path when trying to create a new file on a UDF
filesystem which was internally marked as readonly, but mounted rw:

udf_create
        udf_new_inode
                new_inode
                        alloc_inode
                        	udf_alloc_inode
                udf_new_block
                        returns EIO due to readonlyness
                iput (on error)
                        udf_put_inode
                                udf_discard_prealloc
                                        udf_next_aext
                                                udf_current_aext
                                                        udf_get_fileshortad
                                                                OOPS

the udf_discard_prealloc() path was examining uninitialized fields of the
udf inode.

udf_discard_prealloc() already has this code to short-circuit the discard
path if no extents are preallocated:

        if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB ||
                inode->i_size == UDF_I_LENEXTENTS(inode))
        {
                return;
        }

so if we initialize UDF_I_LENEXTENTS(inode) = 0 earlier in udf_new_inode,
we won't try to free the (not) preallocated blocks, since this will match
the i_size = 0 set when the inode was initialized.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-06 08:57:49 -07:00

167 lines
4.3 KiB
C

/*
* ialloc.c
*
* PURPOSE
* Inode allocation handling routines for the OSTA-UDF(tm) filesystem.
*
* COPYRIGHT
* This file is distributed under the terms of the GNU General Public
* License (GPL). Copies of the GPL can be obtained from:
* ftp://prep.ai.mit.edu/pub/gnu/GPL
* Each contributing author retains all rights to their own work.
*
* (C) 1998-2001 Ben Fennema
*
* HISTORY
*
* 02/24/99 blf Created.
*
*/
#include "udfdecl.h"
#include <linux/fs.h>
#include <linux/quotaops.h>
#include <linux/udf_fs.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include "udf_i.h"
#include "udf_sb.h"
void udf_free_inode(struct inode * inode)
{
struct super_block *sb = inode->i_sb;
struct udf_sb_info *sbi = UDF_SB(sb);
/*
* Note: we must free any quota before locking the superblock,
* as writing the quota to disk may need the lock as well.
*/
DQUOT_FREE_INODE(inode);
DQUOT_DROP(inode);
clear_inode(inode);
mutex_lock(&sbi->s_alloc_mutex);
if (sbi->s_lvidbh) {
if (S_ISDIR(inode->i_mode))
UDF_SB_LVIDIU(sb)->numDirs =
cpu_to_le32(le32_to_cpu(UDF_SB_LVIDIU(sb)->numDirs) - 1);
else
UDF_SB_LVIDIU(sb)->numFiles =
cpu_to_le32(le32_to_cpu(UDF_SB_LVIDIU(sb)->numFiles) - 1);
mark_buffer_dirty(sbi->s_lvidbh);
}
mutex_unlock(&sbi->s_alloc_mutex);
udf_free_blocks(sb, NULL, UDF_I_LOCATION(inode), 0, 1);
}
struct inode * udf_new_inode (struct inode *dir, int mode, int * err)
{
struct super_block *sb = dir->i_sb;
struct udf_sb_info *sbi = UDF_SB(sb);
struct inode * inode;
int block;
uint32_t start = UDF_I_LOCATION(dir).logicalBlockNum;
inode = new_inode(sb);
if (!inode)
{
*err = -ENOMEM;
return NULL;
}
*err = -ENOSPC;
UDF_I_UNIQUE(inode) = 0;
UDF_I_LENEXTENTS(inode) = 0;
UDF_I_NEXT_ALLOC_BLOCK(inode) = 0;
UDF_I_NEXT_ALLOC_GOAL(inode) = 0;
UDF_I_STRAT4096(inode) = 0;
block = udf_new_block(dir->i_sb, NULL, UDF_I_LOCATION(dir).partitionReferenceNum,
start, err);
if (*err)
{
iput(inode);
return NULL;
}
mutex_lock(&sbi->s_alloc_mutex);
if (UDF_SB_LVIDBH(sb))
{
struct logicalVolHeaderDesc *lvhd;
uint64_t uniqueID;
lvhd = (struct logicalVolHeaderDesc *)(UDF_SB_LVID(sb)->logicalVolContentsUse);
if (S_ISDIR(mode))
UDF_SB_LVIDIU(sb)->numDirs =
cpu_to_le32(le32_to_cpu(UDF_SB_LVIDIU(sb)->numDirs) + 1);
else
UDF_SB_LVIDIU(sb)->numFiles =
cpu_to_le32(le32_to_cpu(UDF_SB_LVIDIU(sb)->numFiles) + 1);
UDF_I_UNIQUE(inode) = uniqueID = le64_to_cpu(lvhd->uniqueID);
if (!(++uniqueID & 0x00000000FFFFFFFFUL))
uniqueID += 16;
lvhd->uniqueID = cpu_to_le64(uniqueID);
mark_buffer_dirty(UDF_SB_LVIDBH(sb));
}
inode->i_mode = mode;
inode->i_uid = current->fsuid;
if (dir->i_mode & S_ISGID)
{
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
mode |= S_ISGID;
}
else
inode->i_gid = current->fsgid;
UDF_I_LOCATION(inode).logicalBlockNum = block;
UDF_I_LOCATION(inode).partitionReferenceNum = UDF_I_LOCATION(dir).partitionReferenceNum;
inode->i_ino = udf_get_lb_pblock(sb, UDF_I_LOCATION(inode), 0);
inode->i_blksize = PAGE_SIZE;
inode->i_blocks = 0;
UDF_I_LENEATTR(inode) = 0;
UDF_I_LENALLOC(inode) = 0;
UDF_I_USE(inode) = 0;
if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_EXTENDED_FE))
{
UDF_I_EFE(inode) = 1;
UDF_UPDATE_UDFREV(inode->i_sb, UDF_VERS_USE_EXTENDED_FE);
UDF_I_DATA(inode) = kmalloc(inode->i_sb->s_blocksize - sizeof(struct extendedFileEntry), GFP_KERNEL);
memset(UDF_I_DATA(inode), 0x00, inode->i_sb->s_blocksize - sizeof(struct extendedFileEntry));
}
else
{
UDF_I_EFE(inode) = 0;
UDF_I_DATA(inode) = kmalloc(inode->i_sb->s_blocksize - sizeof(struct fileEntry), GFP_KERNEL);
memset(UDF_I_DATA(inode), 0x00, inode->i_sb->s_blocksize - sizeof(struct fileEntry));
}
if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_AD_IN_ICB))
UDF_I_ALLOCTYPE(inode) = ICBTAG_FLAG_AD_IN_ICB;
else if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
UDF_I_ALLOCTYPE(inode) = ICBTAG_FLAG_AD_SHORT;
else
UDF_I_ALLOCTYPE(inode) = ICBTAG_FLAG_AD_LONG;
inode->i_mtime = inode->i_atime = inode->i_ctime =
UDF_I_CRTIME(inode) = current_fs_time(inode->i_sb);
insert_inode_hash(inode);
mark_inode_dirty(inode);
mutex_unlock(&sbi->s_alloc_mutex);
if (DQUOT_ALLOC_INODE(inode))
{
DQUOT_DROP(inode);
inode->i_flags |= S_NOQUOTA;
inode->i_nlink = 0;
iput(inode);
*err = -EDQUOT;
return NULL;
}
*err = 0;
return inode;
}