From 8045e2985012bdb95d832dfbcceae1815880a6ed Mon Sep 17 00:00:00 2001 From: OGAWA Hirofumi Date: Tue, 12 Jan 2010 03:32:24 +0900 Subject: fat: Fix vfat_lookup() After d_find_alias(), vfat_lookup() checks !(->d_flags & DCACHE_DISCONNECTED) without IS_ROOT(). This means it hits non-anonymous but disconnected dentry. (NOTE: d_splice_alias() doesn't clear DCACHE_DISCONNECTED) But, vfat_lookup() has interest to alias if it was non-anonymous. So, this adds vfat_d_anon_disconn() helper to check it correctly. Another bug is refcnt leak. It needs dput() for uninterested alias. Signed-off-by: OGAWA Hirofumi --- fs/fat/namei_vfat.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c index f565f24..411c192 100644 --- a/fs/fat/namei_vfat.c +++ b/fs/fat/namei_vfat.c @@ -701,6 +701,15 @@ static int vfat_find(struct inode *dir, struct qstr *qname, return fat_search_long(dir, qname->name, len, sinfo); } +/* + * (nfsd's) anonymous disconnected dentry? + * NOTE: !IS_ROOT() is not anonymous (I.e. d_splice_alias() did the job). + */ +static int vfat_d_anon_disconn(struct dentry *dentry) +{ + return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED); +} + static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) { @@ -729,11 +738,11 @@ static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry, } alias = d_find_alias(inode); - if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) { + if (alias && !vfat_d_anon_disconn(alias)) { /* - * This inode has non DCACHE_DISCONNECTED dentry. This - * means, the user did ->lookup() by an another name - * (longname vs 8.3 alias of it) in past. + * This inode has non anonymous-DCACHE_DISCONNECTED + * dentry. This means, the user did ->lookup() by an + * another name (longname vs 8.3 alias of it) in past. * * Switch to new one for reason of locality if possible. */ @@ -743,7 +752,9 @@ static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry, iput(inode); unlock_super(sb); return alias; - } + } else + dput(alias); + out: unlock_super(sb); dentry->d_op = sb->s_root->d_op; -- cgit v1.1 From eeb5b4ae81f4a750355fa0c15f4fea22fdf83be1 Mon Sep 17 00:00:00 2001 From: Kevin Dankwardt Date: Wed, 10 Feb 2010 23:43:40 +0900 Subject: fat: Fix stat->f_namelen I found that the length of a file name when created cannot exceed 255 characters, yet, pathconf(), via statfs(), returns the maximum as 260. Signed-off-by: Kevin Dankwardt Signed-off-by: OGAWA Hirofumi --- fs/fat/inode.c | 2 +- fs/fat/namei_vfat.c | 6 +++--- include/linux/msdos_fs.h | 3 ++- 3 files changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 14da530..d0a504c 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -558,7 +558,7 @@ static int fat_statfs(struct dentry *dentry, struct kstatfs *buf) buf->f_bavail = sbi->free_clusters; buf->f_fsid.val[0] = (u32)id; buf->f_fsid.val[1] = (u32)(id >> 32); - buf->f_namelen = sbi->options.isvfat ? 260 : 12; + buf->f_namelen = sbi->options.isvfat ? FAT_LFN_LEN : 12; return 0; } diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c index 411c192..c1ef501 100644 --- a/fs/fat/namei_vfat.c +++ b/fs/fat/namei_vfat.c @@ -502,14 +502,14 @@ xlate_to_uni(const unsigned char *name, int len, unsigned char *outname, *outlen = utf8s_to_utf16s(name, len, (wchar_t *)outname); if (*outlen < 0) return *outlen; - else if (*outlen > 255) + else if (*outlen > FAT_LFN_LEN) return -ENAMETOOLONG; op = &outname[*outlen * sizeof(wchar_t)]; } else { if (nls) { for (i = 0, ip = name, op = outname, *outlen = 0; - i < len && *outlen <= 255; + i < len && *outlen <= FAT_LFN_LEN; *outlen += 1) { if (escape && (*ip == ':')) { @@ -549,7 +549,7 @@ xlate_to_uni(const unsigned char *name, int len, unsigned char *outname, return -ENAMETOOLONG; } else { for (i = 0, ip = name, op = outname, *outlen = 0; - i < len && *outlen <= 255; + i < len && *outlen <= FAT_LFN_LEN; i++, *outlen += 1) { *op++ = *ip++; diff --git a/include/linux/msdos_fs.h b/include/linux/msdos_fs.h index ce38f1c..34066e6 100644 --- a/include/linux/msdos_fs.h +++ b/include/linux/msdos_fs.h @@ -15,6 +15,7 @@ #define MSDOS_DPB_BITS 4 /* log2(MSDOS_DPB) */ #define MSDOS_DPS (SECTOR_SIZE / sizeof(struct msdos_dir_entry)) #define MSDOS_DPS_BITS 4 /* log2(MSDOS_DPS) */ +#define MSDOS_LONGNAME 256 /* maximum name length */ #define CF_LE_W(v) le16_to_cpu(v) #define CF_LE_L(v) le32_to_cpu(v) #define CT_LE_W(v) cpu_to_le16(v) @@ -47,8 +48,8 @@ #define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */ #define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG) +#define FAT_LFN_LEN 255 /* maximum long name length */ #define MSDOS_NAME 11 /* maximum name length */ -#define MSDOS_LONGNAME 256 /* maximum name length */ #define MSDOS_SLOTS 21 /* max # of slots for short and long names */ #define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */ #define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */ -- cgit v1.1