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libext2fs: fix potential resource leak in ext2fs_file_write
[tools/e2fsprogs.git] / lib / ext2fs / fileio.c
index 6b213b5..a0b5d97 100644 (file)
@@ -18,6 +18,7 @@
 
 #include "ext2_fs.h"
 #include "ext2fs.h"
+#include "ext2fsP.h"
 
 struct ext2_file {
        errcode_t               magic;
@@ -31,6 +32,12 @@ struct ext2_file {
        char                    *buf;
 };
 
+struct block_entry {
+       blk64_t         physblock;
+       unsigned char   sha[EXT2FS_SHA512_LENGTH];
+};
+typedef struct block_entry *block_entry_t;
+
 #define BMAP_BUFFER (file->buf + fs->blocksize)
 
 errcode_t ext2fs_file_open2(ext2_filsys fs, ext2_ino_t ino,
@@ -122,6 +129,8 @@ errcode_t ext2fs_file_flush(ext2_file_t file)
 {
        errcode_t       retval;
        ext2_filsys fs;
+       int             ret_flags;
+       blk64_t         dontcare;
 
        EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
        fs = file->fs;
@@ -130,6 +139,22 @@ errcode_t ext2fs_file_flush(ext2_file_t file)
            !(file->flags & EXT2_FILE_BUF_DIRTY))
                return 0;
 
+       /* Is this an uninit block? */
+       if (file->physblock && file->inode.i_flags & EXT4_EXTENTS_FL) {
+               retval = ext2fs_bmap2(fs, file->ino, &file->inode, BMAP_BUFFER,
+                                     0, file->blockno, &ret_flags, &dontcare);
+               if (retval)
+                       return retval;
+               if (ret_flags & BMAP_RET_UNINIT) {
+                       retval = ext2fs_bmap2(fs, file->ino, &file->inode,
+                                             BMAP_BUFFER, BMAP_SET,
+                                             file->blockno, 0,
+                                             &file->physblock);
+                       if (retval)
+                               return retval;
+               }
+       }
+
        /*
         * OK, the physical block hasn't been allocated yet.
         * Allocate it.
@@ -142,8 +167,7 @@ errcode_t ext2fs_file_flush(ext2_file_t file)
                        return retval;
        }
 
-       retval = io_channel_write_blk(fs->io, file->physblock,
-                                     1, file->buf);
+       retval = io_channel_write_blk64(fs->io, file->physblock, 1, file->buf);
        if (retval)
                return retval;
 
@@ -185,18 +209,20 @@ static errcode_t load_buffer(ext2_file_t file, int dontfill)
 {
        ext2_filsys     fs = file->fs;
        errcode_t       retval;
+       int             ret_flags;
 
        if (!(file->flags & EXT2_FILE_BUF_VALID)) {
                retval = ext2fs_bmap2(fs, file->ino, &file->inode,
-                                    BMAP_BUFFER, 0, file->blockno, 0,
+                                    BMAP_BUFFER, 0, file->blockno, &ret_flags,
                                     &file->physblock);
                if (retval)
                        return retval;
                if (!dontfill) {
-                       if (file->physblock) {
-                               retval = io_channel_read_blk(fs->io,
-                                                            file->physblock,
-                                                            1, file->buf);
+                       if (file->physblock &&
+                           !(ret_flags & BMAP_RET_UNINIT)) {
+                               retval = io_channel_read_blk64(fs->io,
+                                                              file->physblock,
+                                                              1, file->buf);
                                if (retval)
                                        return retval;
                        } else
@@ -224,6 +250,38 @@ errcode_t ext2fs_file_close(ext2_file_t file)
 }
 
 
+static errcode_t
+ext2fs_file_read_inline_data(ext2_file_t file, void *buf,
+                            unsigned int wanted, unsigned int *got)
+{
+       ext2_filsys fs;
+       errcode_t retval;
+       unsigned int count = 0;
+       size_t size;
+
+       fs = file->fs;
+       retval = ext2fs_inline_data_get(fs, file->ino, &file->inode,
+                                       file->buf, &size);
+       if (retval)
+               return retval;
+
+       if (file->pos >= size)
+               goto out;
+
+       count = size - file->pos;
+       if (count > wanted)
+               count = wanted;
+       memcpy(buf, file->buf + file->pos, count);
+       file->pos += count;
+       buf = (char *) buf + count;
+
+out:
+       if (got)
+               *got = count;
+       return retval;
+}
+
+
 errcode_t ext2fs_file_read(ext2_file_t file, void *buf,
                           unsigned int wanted, unsigned int *got)
 {
@@ -236,6 +294,10 @@ errcode_t ext2fs_file_read(ext2_file_t file, void *buf,
        EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
        fs = file->fs;
 
+       /* If an inode has inline data, things get complicated. */
+       if (file->inode.i_flags & EXT4_INLINE_DATA_FL)
+               return ext2fs_file_read_inline_data(file, buf, wanted, got);
+
        while ((file->pos < EXT2_I_SIZE(&file->inode)) && (wanted > 0)) {
                retval = sync_buffer_position(file);
                if (retval)
@@ -266,6 +328,66 @@ fail:
 }
 
 
+static errcode_t
+ext2fs_file_write_inline_data(ext2_file_t file, const void *buf,
+                             unsigned int nbytes, unsigned int *written)
+{
+       ext2_filsys fs;
+       errcode_t retval;
+       unsigned int count = 0;
+       size_t size;
+
+       fs = file->fs;
+       retval = ext2fs_inline_data_get(fs, file->ino, &file->inode,
+                                       file->buf, &size);
+       if (retval)
+               return retval;
+
+       if (file->pos < size) {
+               count = nbytes - file->pos;
+               memcpy(file->buf + file->pos, buf, count);
+
+               retval = ext2fs_inline_data_set(fs, file->ino, &file->inode,
+                                               file->buf, count);
+               if (retval == EXT2_ET_INLINE_DATA_NO_SPACE)
+                       goto expand;
+               if (retval)
+                       return retval;
+
+               file->pos += count;
+
+               /* Update inode size */
+               if (count != 0 && EXT2_I_SIZE(&file->inode) < file->pos) {
+                       errcode_t       rc;
+
+                       rc = ext2fs_file_set_size2(file, file->pos);
+                       if (retval == 0)
+                               retval = rc;
+               }
+
+               if (written)
+                       *written = count;
+               return 0;
+       }
+
+expand:
+       retval = ext2fs_inline_data_expand(fs, file->ino);
+       if (retval)
+               return retval;
+       /*
+        * reload inode and return no space error
+        *
+        * XXX: file->inode could be copied from the outside
+        * in ext2fs_file_open2().  We have no way to modify
+        * the outside inode.
+        */
+       retval = ext2fs_read_inode(fs, file->ino, &file->inode);
+       if (retval)
+               return retval;
+       return EXT2_ET_INLINE_DATA_NO_SPACE;
+}
+
+
 errcode_t ext2fs_file_write(ext2_file_t file, const void *buf,
                            unsigned int nbytes, unsigned int *written)
 {
@@ -273,6 +395,8 @@ errcode_t ext2fs_file_write(ext2_file_t file, const void *buf,
        errcode_t       retval = 0;
        unsigned int    start, c, count = 0;
        const char      *ptr = (const char *) buf;
+       block_entry_t   new_block = NULL, old_block = NULL;
+       int             bmap_flags = 0;
 
        EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
        fs = file->fs;
@@ -280,6 +404,16 @@ errcode_t ext2fs_file_write(ext2_file_t file, const void *buf,
        if (!(file->flags & EXT2_FILE_WRITE))
                return EXT2_ET_FILE_RO;
 
+       /* If an inode has inline data, things get complicated. */
+       if (file->inode.i_flags & EXT4_INLINE_DATA_FL) {
+               retval = ext2fs_file_write_inline_data(file, buf, nbytes,
+                                                      written);
+               if (retval != EXT2_ET_INLINE_DATA_NO_SPACE)
+                       return retval;
+               /* fall through to read data from the block */
+               retval = 0;
+       }
+
        while (nbytes > 0) {
                retval = sync_buffer_position(file);
                if (retval)
@@ -300,6 +434,57 @@ errcode_t ext2fs_file_write(ext2_file_t file, const void *buf,
 
                file->flags |= EXT2_FILE_BUF_DIRTY;
                memcpy(file->buf+start, ptr, c);
+
+               /*
+                * OK, the physical block hasn't been allocated yet.
+                * Allocate it.
+                */
+               if (!file->physblock) {
+                       bmap_flags = (file->ino ? BMAP_ALLOC : 0);
+                       if (fs->flags & EXT2_FLAG_SHARE_DUP) {
+                               new_block = calloc(1, sizeof(*new_block));
+                               if (!new_block) {
+                                       retval = EXT2_ET_NO_MEMORY;
+                                       goto fail;
+                               }
+                               ext2fs_sha512((const unsigned char*)file->buf,
+                                               fs->blocksize, new_block->sha);
+                               old_block = ext2fs_hashmap_lookup(
+                                                       fs->block_sha_map,
+                                                       new_block->sha,
+                                                       sizeof(new_block->sha));
+                       }
+
+                       if (old_block) {
+                               file->physblock = old_block->physblock;
+                               bmap_flags |= BMAP_SET;
+                               free(new_block);
+                               new_block = NULL;
+                       }
+
+                       retval = ext2fs_bmap2(fs, file->ino, &file->inode,
+                                             BMAP_BUFFER,
+                                             bmap_flags,
+                                             file->blockno, 0,
+                                             &file->physblock);
+                       if (retval) {
+                               free(new_block);
+                               new_block = NULL;
+                               goto fail;
+                       }
+
+                       if (new_block) {
+                               new_block->physblock = file->physblock;
+                               ext2fs_hashmap_add(fs->block_sha_map, new_block,
+                                       new_block->sha, sizeof(new_block->sha));
+                       }
+
+                       if (bmap_flags & BMAP_SET) {
+                               ext2fs_iblk_add_blocks(fs, &file->inode, 1);
+                               ext2fs_write_inode(fs, file->ino, &file->inode);
+                       }
+               }
+
                file->pos += c;
                ptr += c;
                count += c;
@@ -344,7 +529,7 @@ errcode_t ext2fs_file_llseek(ext2_file_t file, __u64 offset,
 errcode_t ext2fs_file_lseek(ext2_file_t file, ext2_off_t offset,
                            int whence, ext2_off_t *ret_pos)
 {
-       __u64           loffset, ret_loffset;
+       __u64           loffset, ret_loffset = 0;
        errcode_t       retval;
 
        loffset = offset;
@@ -380,6 +565,53 @@ ext2_off_t ext2fs_file_get_size(ext2_file_t file)
        return size;
 }
 
+/* Zero the parts of the last block that are past EOF. */
+static errcode_t ext2fs_file_zero_past_offset(ext2_file_t file,
+                                             ext2_off64_t offset)
+{
+       ext2_filsys fs = file->fs;
+       char *b = NULL;
+       ext2_off64_t off = offset % fs->blocksize;
+       blk64_t blk;
+       int ret_flags;
+       errcode_t retval;
+
+       if (off == 0)
+               return 0;
+
+       retval = sync_buffer_position(file);
+       if (retval)
+               return retval;
+
+       /* Is there an initialized block at the end? */
+       retval = ext2fs_bmap2(fs, file->ino, NULL, NULL, 0,
+                             offset / fs->blocksize, &ret_flags, &blk);
+       if (retval)
+               return retval;
+       if ((blk == 0) || (ret_flags & BMAP_RET_UNINIT))
+               return 0;
+
+       /* Zero to the end of the block */
+       retval = ext2fs_get_mem(fs->blocksize, &b);
+       if (retval)
+               return retval;
+
+       /* Read/zero/write block */
+       retval = io_channel_read_blk64(fs->io, blk, 1, b);
+       if (retval)
+               goto out;
+
+       memset(b + off, 0, fs->blocksize - off);
+
+       retval = io_channel_write_blk64(fs->io, blk, 1, b);
+       if (retval)
+               goto out;
+
+out:
+       ext2fs_free_mem(&b);
+       return retval;
+}
+
 /*
  * This function sets the size of the file, truncating it if necessary
  *
@@ -392,32 +624,29 @@ errcode_t ext2fs_file_set_size2(ext2_file_t file, ext2_off64_t size)
 
        EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
 
+       if (size && ext2fs_file_block_offset_too_big(file->fs, &file->inode,
+                                       (size - 1) / file->fs->blocksize))
+               return EXT2_ET_FILE_TOO_BIG;
        truncate_block = ((size + file->fs->blocksize - 1) >>
                          EXT2_BLOCK_SIZE_BITS(file->fs->super));
        old_size = EXT2_I_SIZE(&file->inode);
        old_truncate = ((old_size + file->fs->blocksize - 1) >>
                      EXT2_BLOCK_SIZE_BITS(file->fs->super));
 
-       /* If we're writing a large file, set the large_file flag */
-       if (LINUX_S_ISREG(file->inode.i_mode) &&
-           ext2fs_needs_large_file_feature(EXT2_I_SIZE(&file->inode)) &&
-           (!EXT2_HAS_RO_COMPAT_FEATURE(file->fs->super,
-                                        EXT2_FEATURE_RO_COMPAT_LARGE_FILE) ||
-            file->fs->super->s_rev_level == EXT2_GOOD_OLD_REV)) {
-               file->fs->super->s_feature_ro_compat |=
-                               EXT2_FEATURE_RO_COMPAT_LARGE_FILE;
-               ext2fs_update_dynamic_rev(file->fs);
-               ext2fs_mark_super_dirty(file->fs);
-       }
+       retval = ext2fs_inode_size_set(file->fs, &file->inode, size);
+       if (retval)
+               return retval;
 
-       file->inode.i_size = size & 0xffffffff;
-       file->inode.i_size_high = (size >> 32);
        if (file->ino) {
                retval = ext2fs_write_inode(file->fs, file->ino, &file->inode);
                if (retval)
                        return retval;
        }
 
+       retval = ext2fs_file_zero_past_offset(file, size);
+       if (retval)
+               return retval;
+
        if (truncate_block >= old_truncate)
                return 0;