From 785dffe1daf95c176504dea3069c9df11af7ff15 Mon Sep 17 00:00:00 2001 From: Chengguang Xu Date: Sun, 25 Feb 2018 21:25:07 +0800 Subject: [PATCH] udf: fix potential refcnt problem of nls module When specifiying iocharset multiple times in a mount or once/multiple in a remount, current option parsing may cause inaccurate refcount of nls module. Also, in the failure cleanup of option parsing, the condition of calling unload_nls is not sufficient. Signed-off-by: Chengguang Xu Signed-off-by: Jan Kara --- fs/udf/super.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/fs/udf/super.c b/fs/udf/super.c index bf5f6084dcb2..7949c338efa5 100644 --- a/fs/udf/super.c +++ b/fs/udf/super.c @@ -477,7 +477,6 @@ static int udf_parse_options(char *options, struct udf_options *uopt, uopt->session = 0xFFFFFFFF; uopt->lastblock = 0; uopt->anchor = 0; - uopt->nls_map = NULL; if (!options) return 1; @@ -575,8 +574,12 @@ static int udf_parse_options(char *options, struct udf_options *uopt, break; #ifdef CONFIG_UDF_NLS case Opt_iocharset: - uopt->nls_map = load_nls(args[0].from); - uopt->flags |= (1 << UDF_FLAG_NLS_MAP); + if (!remount) { + if (uopt->nls_map) + unload_nls(uopt->nls_map); + uopt->nls_map = load_nls(args[0].from); + uopt->flags |= (1 << UDF_FLAG_NLS_MAP); + } break; #endif case Opt_uforget: @@ -627,6 +630,7 @@ static int udf_remount_fs(struct super_block *sb, int *flags, char *options) uopt.umask = sbi->s_umask; uopt.fmode = sbi->s_fmode; uopt.dmode = sbi->s_dmode; + uopt.nls_map = NULL; if (!udf_parse_options(options, &uopt, true)) return -EINVAL; @@ -2095,6 +2099,7 @@ static int udf_fill_super(struct super_block *sb, void *options, int silent) uopt.umask = 0; uopt.fmode = UDF_INVALID_MODE; uopt.dmode = UDF_INVALID_MODE; + uopt.nls_map = NULL; sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); if (!sbi) @@ -2275,8 +2280,8 @@ error_out: iput(sbi->s_vat_inode); parse_options_failure: #ifdef CONFIG_UDF_NLS - if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) - unload_nls(sbi->s_nls_map); + if (uopt.nls_map) + unload_nls(uopt.nls_map); #endif if (lvid_open) udf_close_lvid(sb); -- 2.30.2