From 066b9cded00b8e3212df74a417bb074f3f3a1fe0 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 26 Jan 2016 21:07:30 +0100 Subject: [PATCH] udf: Use separate buffer for copying split names Code in udf_find_entry() and udf_readdir() used the same buffer for storing filename that was split among blocks and for the resulting filename in utf8. This worked because udf_get_filename() first internally copied the name into a different buffer and only then performed a conversion into the destination buffer. However we want to get rid of intermediate buffers so use separate buffer for converted name and name split between blocks so that we don't have the same source and destination buffer when converting split names. Signed-off-by: Jan Kara --- fs/udf/dir.c | 13 +++++++++++-- fs/udf/namei.c | 13 +++++++++++-- 2 files changed, 22 insertions(+), 4 deletions(-) diff --git a/fs/udf/dir.c b/fs/udf/dir.c index 541d9c65014d..b51b371b874a 100644 --- a/fs/udf/dir.c +++ b/fs/udf/dir.c @@ -45,7 +45,7 @@ static int udf_readdir(struct file *file, struct dir_context *ctx) int block, iblock; loff_t nf_pos; int flen; - unsigned char *fname = NULL; + unsigned char *fname = NULL, *copy_name = NULL; unsigned char *nameptr; uint16_t liu; uint8_t lfi; @@ -143,7 +143,15 @@ static int udf_readdir(struct file *file, struct dir_context *ctx) if (poffset >= lfi) { nameptr = (char *)(fibh.ebh->b_data + poffset - lfi); } else { - nameptr = fname; + if (!copy_name) { + copy_name = kmalloc(UDF_NAME_LEN, + GFP_NOFS); + if (!copy_name) { + ret = -ENOMEM; + goto out; + } + } + nameptr = copy_name; memcpy(nameptr, fi->fileIdent + liu, lfi - poffset); memcpy(nameptr + lfi - poffset, @@ -185,6 +193,7 @@ out: brelse(fibh.sbh); brelse(epos.bh); kfree(fname); + kfree(copy_name); return ret; } diff --git a/fs/udf/namei.c b/fs/udf/namei.c index 9eb9c6440270..a2ba11eca995 100644 --- a/fs/udf/namei.c +++ b/fs/udf/namei.c @@ -165,7 +165,7 @@ static struct fileIdentDesc *udf_find_entry(struct inode *dir, struct fileIdentDesc *fi = NULL; loff_t f_pos; int block, flen; - unsigned char *fname = NULL; + unsigned char *fname = NULL, *copy_name = NULL; unsigned char *nameptr; uint8_t lfi; uint16_t liu; @@ -236,7 +236,15 @@ static struct fileIdentDesc *udf_find_entry(struct inode *dir, nameptr = (uint8_t *)(fibh->ebh->b_data + poffset - lfi); else { - nameptr = fname; + if (!copy_name) { + copy_name = kmalloc(UDF_NAME_LEN, + GFP_NOFS); + if (!copy_name) { + fi = ERR_PTR(-ENOMEM); + goto out_err; + } + } + nameptr = copy_name; memcpy(nameptr, fi->fileIdent + liu, lfi - poffset); memcpy(nameptr + lfi - poffset, @@ -279,6 +287,7 @@ out_err: out_ok: brelse(epos.bh); kfree(fname); + kfree(copy_name); return fi; }