fs: Make unload_nls() NULL pointer safe
Thomas Gleixner [Sun, 16 Aug 2009 21:05:08 +0000 (21:05 +0000)]
Most call sites of unload_nls() do:
if (nls)
unload_nls(nls);

Check the pointer inside unload_nls() like we do in kfree() and
simplify the call sites.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Steve French <sfrench@us.ibm.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

12 files changed:
fs/befs/linuxvfs.c
fs/cifs/cifsfs.c
fs/fat/inode.c
fs/hfs/mdb.c
fs/hfsplus/super.c
fs/isofs/inode.c
fs/jfs/super.c
fs/ncpfs/inode.c
fs/ncpfs/ioctl.c
fs/nls/nls_base.c
fs/ntfs/super.c
fs/smbfs/inode.c

index dd376c1..33baf27 100644 (file)
@@ -737,12 +737,7 @@ befs_put_super(struct super_block *sb)
 {
        kfree(BEFS_SB(sb)->mount_opts.iocharset);
        BEFS_SB(sb)->mount_opts.iocharset = NULL;
-
-       if (BEFS_SB(sb)->nls) {
-               unload_nls(BEFS_SB(sb)->nls);
-               BEFS_SB(sb)->nls = NULL;
-       }
-
+       unload_nls(BEFS_SB(sb)->nls);
        kfree(sb->s_fs_info);
        sb->s_fs_info = NULL;
 }
index d79ce2e..90c5b39 100644 (file)
@@ -185,8 +185,7 @@ out_mount_failed:
                        cifs_sb->mountdata = NULL;
                }
 #endif
-               if (cifs_sb->local_nls)
-                       unload_nls(cifs_sb->local_nls);
+               unload_nls(cifs_sb->local_nls);
                kfree(cifs_sb);
        }
        return rc;
index 8970d8c..04629d1 100644 (file)
@@ -470,19 +470,11 @@ static void fat_put_super(struct super_block *sb)
 
        iput(sbi->fat_inode);
 
-       if (sbi->nls_disk) {
-               unload_nls(sbi->nls_disk);
-               sbi->nls_disk = NULL;
-               sbi->options.codepage = fat_default_codepage;
-       }
-       if (sbi->nls_io) {
-               unload_nls(sbi->nls_io);
-               sbi->nls_io = NULL;
-       }
-       if (sbi->options.iocharset != fat_default_iocharset) {
+       unload_nls(sbi->nls_disk);
+       unload_nls(sbi->nls_io);
+
+       if (sbi->options.iocharset != fat_default_iocharset)
                kfree(sbi->options.iocharset);
-               sbi->options.iocharset = fat_default_iocharset;
-       }
 
        sb->s_fs_info = NULL;
        kfree(sbi);
index 7b6165f..8bbe03c 100644 (file)
@@ -344,10 +344,8 @@ void hfs_mdb_put(struct super_block *sb)
        brelse(HFS_SB(sb)->mdb_bh);
        brelse(HFS_SB(sb)->alt_mdb_bh);
 
-       if (HFS_SB(sb)->nls_io)
-               unload_nls(HFS_SB(sb)->nls_io);
-       if (HFS_SB(sb)->nls_disk)
-               unload_nls(HFS_SB(sb)->nls_disk);
+       unload_nls(HFS_SB(sb)->nls_io);
+       unload_nls(HFS_SB(sb)->nls_disk);
 
        free_pages((unsigned long)HFS_SB(sb)->bitmap, PAGE_SIZE < 8192 ? 1 : 0);
        kfree(HFS_SB(sb));
index c0759fe..43022f3 100644 (file)
@@ -229,8 +229,7 @@ static void hfsplus_put_super(struct super_block *sb)
        iput(HFSPLUS_SB(sb).alloc_file);
        iput(HFSPLUS_SB(sb).hidden_dir);
        brelse(HFSPLUS_SB(sb).s_vhbh);
-       if (HFSPLUS_SB(sb).nls)
-               unload_nls(HFSPLUS_SB(sb).nls);
+       unload_nls(HFSPLUS_SB(sb).nls);
        kfree(sb->s_fs_info);
        sb->s_fs_info = NULL;
 
@@ -464,8 +463,7 @@ out:
 
 cleanup:
        hfsplus_put_super(sb);
-       if (nls)
-               unload_nls(nls);
+       unload_nls(nls);
        return err;
 }
 
index 85f96bc..6b4dcd4 100644 (file)
@@ -46,10 +46,7 @@ static void isofs_put_super(struct super_block *sb)
 #ifdef CONFIG_JOLIET
        lock_kernel();
 
-       if (sbi->s_nls_iocharset) {
-               unload_nls(sbi->s_nls_iocharset);
-               sbi->s_nls_iocharset = NULL;
-       }
+       unload_nls(sbi->s_nls_iocharset);
 
        unlock_kernel();
 #endif
@@ -912,8 +909,7 @@ out_no_root:
                printk(KERN_WARNING "%s: get root inode failed\n", __func__);
 out_no_inode:
 #ifdef CONFIG_JOLIET
-       if (sbi->s_nls_iocharset)
-               unload_nls(sbi->s_nls_iocharset);
+       unload_nls(sbi->s_nls_iocharset);
 #endif
        goto out_freesbi;
 out_no_read:
index 37e6dcd..2234c73 100644 (file)
@@ -178,13 +178,11 @@ static void jfs_put_super(struct super_block *sb)
        rc = jfs_umount(sb);
        if (rc)
                jfs_err("jfs_umount failed with return code %d", rc);
-       if (sbi->nls_tab)
-               unload_nls(sbi->nls_tab);
-       sbi->nls_tab = NULL;
+
+       unload_nls(sbi->nls_tab);
 
        truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
        iput(sbi->direct_inode);
-       sbi->direct_inode = NULL;
 
        kfree(sbi);
 
@@ -347,8 +345,7 @@ static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
 
        if (nls_map != (void *) -1) {
                /* Discard old (if remount) */
-               if (sbi->nls_tab)
-                       unload_nls(sbi->nls_tab);
+               unload_nls(sbi->nls_tab);
                sbi->nls_tab = nls_map;
        }
        return 1;
index b99ce20..cf98da1 100644 (file)
@@ -746,16 +746,8 @@ static void ncp_put_super(struct super_block *sb)
 
 #ifdef CONFIG_NCPFS_NLS
        /* unload the NLS charsets */
-       if (server->nls_vol)
-       {
-               unload_nls(server->nls_vol);
-               server->nls_vol = NULL;
-       }
-       if (server->nls_io)
-       {
-               unload_nls(server->nls_io);
-               server->nls_io = NULL;
-       }
+       unload_nls(server->nls_vol);
+       unload_nls(server->nls_io);
 #endif /* CONFIG_NCPFS_NLS */
 
        if (server->info_filp)
index 53a7ed7..0d58caf 100644 (file)
@@ -223,10 +223,8 @@ ncp_set_charsets(struct ncp_server* server, struct ncp_nls_ioctl __user *arg)
        oldset_io = server->nls_io;
        server->nls_io = iocharset;
 
-       if (oldset_cp)
-               unload_nls(oldset_cp);
-       if (oldset_io)
-               unload_nls(oldset_io);
+       unload_nls(oldset_cp);
+       unload_nls(oldset_io);
 
        return 0;
 }
index 477d37d..2224b4d 100644 (file)
@@ -270,7 +270,8 @@ struct nls_table *load_nls(char *charset)
 
 void unload_nls(struct nls_table *nls)
 {
-       module_put(nls->owner);
+       if (nls)
+               module_put(nls->owner);
 }
 
 static const wchar_t charset2uni[256] = {
index abaaa1c..80b0477 100644 (file)
@@ -201,8 +201,7 @@ use_utf8:
                                                v, old_nls->charset);
                                nls_map = old_nls;
                        } else /* nls_map */ {
-                               if (old_nls)
-                                       unload_nls(old_nls);
+                               unload_nls(old_nls);
                        }
                } else if (!strcmp(p, "utf8")) {
                        bool val = false;
@@ -2427,10 +2426,9 @@ static void ntfs_put_super(struct super_block *sb)
                ntfs_free(vol->upcase);
                vol->upcase = NULL;
        }
-       if (vol->nls_map) {
-               unload_nls(vol->nls_map);
-               vol->nls_map = NULL;
-       }
+
+       unload_nls(vol->nls_map);
+
        sb->s_fs_info = NULL;
        kfree(vol);
 
index 1402d2d..1c4c8f0 100644 (file)
@@ -459,14 +459,8 @@ smb_show_options(struct seq_file *s, struct vfsmount *m)
 static void
 smb_unload_nls(struct smb_sb_info *server)
 {
-       if (server->remote_nls) {
-               unload_nls(server->remote_nls);
-               server->remote_nls = NULL;
-       }
-       if (server->local_nls) {
-               unload_nls(server->local_nls);
-               server->local_nls = NULL;
-       }
+       unload_nls(server->remote_nls);
+       unload_nls(server->local_nls);
 }
 
 static void