diff options
| -rw-r--r-- | fs/namei.c | 59 |
1 files changed, 22 insertions, 37 deletions
diff --git a/fs/namei.c b/fs/namei.c index def63e7c058d..63844776484c 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2114,7 +2114,10 @@ static struct file *do_last(struct nameidata *nd, struct path *path, const struct open_flags *op, const char *pathname) { struct dentry *dir = nd->path.dentry; + int open_flag = op->open_flag; int will_truncate; + int want_write = 0; + int skip_perm = 0; struct file *filp; struct inode *inode; int error; @@ -2138,7 +2141,7 @@ static struct file *do_last(struct nameidata *nd, struct path *path, if (error) goto exit; audit_inode(pathname, nd->path.dentry); - if (op->open_flag & O_CREAT) { + if (open_flag & O_CREAT) { error = -EISDIR; goto exit; } @@ -2152,7 +2155,7 @@ static struct file *do_last(struct nameidata *nd, struct path *path, goto ok; } - if (!(op->open_flag & O_CREAT)) { + if (!(open_flag & O_CREAT)) { if (nd->last.name[nd->last.len]) nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY; /* we _can_ be in RCU mode here */ @@ -2230,28 +2233,15 @@ static struct file *do_last(struct nameidata *nd, struct path *path, error = mnt_want_write(nd->path.mnt); if (error) goto exit_mutex_unlock; - error = __open_namei_create(nd, path, op->open_flag, op->mode); - if (error) { - mnt_drop_write(nd->path.mnt); + want_write = 1; + will_truncate = 0; + error = __open_namei_create(nd, path, open_flag, op->mode); + if (error) goto exit; - } /* Don't check for write permission, don't truncate */ - error = may_open(&nd->path, 0, op->open_flag & ~O_TRUNC); - if (error) { - mnt_drop_write(nd->path.mnt); - goto exit; - } - filp = nameidata_to_filp(nd); - mnt_drop_write(nd->path.mnt); - path_put(&nd->path); - if (!IS_ERR(filp)) { - error = ima_file_check(filp, op->acc_mode); - if (error) { - fput(filp); - filp = ERR_PTR(error); - } - } - return filp; + open_flag &= ~O_TRUNC; + skip_perm = 1; + goto common; } /* @@ -2261,7 +2251,7 @@ static struct file *do_last(struct nameidata *nd, struct path *path, audit_inode(pathname, path->dentry); error = -EEXIST; - if (op->open_flag & O_EXCL) + if (open_flag & O_EXCL) goto exit_dput; error = follow_managed(path, nd->flags); @@ -2281,18 +2271,17 @@ static struct file *do_last(struct nameidata *nd, struct path *path, if (S_ISDIR(nd->inode->i_mode)) goto exit; ok: - will_truncate = open_will_truncate(op->open_flag, nd->path.dentry->d_inode); + will_truncate = open_will_truncate(open_flag, nd->path.dentry->d_inode); if (will_truncate) { error = mnt_want_write(nd->path.mnt); if (error) goto exit; + want_write = 1; } - error = may_open(&nd->path, op->acc_mode, op->open_flag); - if (error) { - if (will_truncate) - mnt_drop_write(nd->path.mnt); +common: + error = may_open(&nd->path, skip_perm ? 0 : op->acc_mode, open_flag); + if (error) goto exit; - } filp = nameidata_to_filp(nd); if (!IS_ERR(filp)) { error = ima_file_check(filp, op->acc_mode); @@ -2310,12 +2299,8 @@ ok: } } } - /* - * It is now safe to drop the mnt write - * because the filp has had a write taken - * on its behalf. - */ - if (will_truncate) +out: + if (want_write) mnt_drop_write(nd->path.mnt); path_put(&nd->path); return filp; @@ -2325,8 +2310,8 @@ exit_mutex_unlock: exit_dput: path_put_conditional(path, nd); exit: - path_put(&nd->path); - return ERR_PTR(error); + filp = ERR_PTR(error); + goto out; } static struct file *path_openat(int dfd, const char *pathname, |