From 6fdcc2162285a8fc96ab12ff85086c37bceaa494 Mon Sep 17 00:00:00 2001 From: Peter Staubach Date: Mon, 7 Nov 2005 00:59:42 -0800 Subject: [PATCH] memory leak in dentry_open() There is a memory leak possible in dentry_open(). If get_empty_filp() fails, then the references to dentry and mnt need to be released. The attached patch adds the calls to dput() and mntput() to release these two references. Signed-off-by: Peter Staubach Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/open.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'fs/open.c') diff --git a/fs/open.c b/fs/open.c index 8d06ec911fd9..2835f096c683 100644 --- a/fs/open.c +++ b/fs/open.c @@ -887,6 +887,10 @@ struct file *nameidata_to_filp(struct nameidata *nd, int flags) return filp; } +/* + * dentry_open() will have done dput(dentry) and mntput(mnt) if it returns an + * error. + */ struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags) { int error; @@ -894,8 +898,11 @@ struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags) error = -ENFILE; f = get_empty_filp(); - if (f == NULL) + if (f == NULL) { + dput(dentry); + mntput(mnt); return ERR_PTR(error); + } return __dentry_open(dentry, mnt, flags, f, NULL); } -- cgit From cc4e69dee4a080f6eae3f410daec2593f4fa6f00 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Mon, 7 Nov 2005 00:59:49 -0800 Subject: [PATCH] VFS: pass file pointer to filesystem from ftruncate() This patch extends the iattr structure with a file pointer memeber, and adds an ATTR_FILE validity flag for this member. This is set if do_truncate() is invoked from ftruncate() or from do_coredump(). The change is source and binary compatible. Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/open.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'fs/open.c') diff --git a/fs/open.c b/fs/open.c index 2835f096c683..6e8136751e9a 100644 --- a/fs/open.c +++ b/fs/open.c @@ -194,7 +194,7 @@ out: return error; } -int do_truncate(struct dentry *dentry, loff_t length) +int do_truncate(struct dentry *dentry, loff_t length, struct file *filp) { int err; struct iattr newattrs; @@ -205,6 +205,10 @@ int do_truncate(struct dentry *dentry, loff_t length) newattrs.ia_size = length; newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME; + if (filp) { + newattrs.ia_file = filp; + newattrs.ia_valid |= ATTR_FILE; + } down(&dentry->d_inode->i_sem); err = notify_change(dentry, &newattrs); @@ -262,7 +266,7 @@ static inline long do_sys_truncate(const char __user * path, loff_t length) error = locks_verify_truncate(inode, NULL, length); if (!error) { DQUOT_INIT(inode); - error = do_truncate(nd.dentry, length); + error = do_truncate(nd.dentry, length, NULL); } put_write_access(inode); @@ -314,7 +318,7 @@ static inline long do_sys_ftruncate(unsigned int fd, loff_t length, int small) error = locks_verify_truncate(inode, file, length); if (!error) - error = do_truncate(dentry, length); + error = do_truncate(dentry, length, file); out_putf: fput(file); out: -- cgit From e4543eddfd3bf3e0d625841377fa695a519edfd4 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 8 Nov 2005 21:35:04 -0800 Subject: [PATCH] add a vfs_permission helper Most permission() calls have a struct nameidata * available. This helper takes that as an argument and thus makes sure we pass it down for lookup intents and prepares for per-mount read-only support where we need a struct vfsmount for checking whether a file is writeable. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/open.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'fs/open.c') diff --git a/fs/open.c b/fs/open.c index 6e8136751e9a..baffc084580d 100644 --- a/fs/open.c +++ b/fs/open.c @@ -240,7 +240,7 @@ static inline long do_sys_truncate(const char __user * path, loff_t length) if (!S_ISREG(inode->i_mode)) goto dput_and_out; - error = permission(inode,MAY_WRITE,&nd); + error = vfs_permission(&nd, MAY_WRITE); if (error) goto dput_and_out; @@ -394,7 +394,7 @@ asmlinkage long sys_utime(char __user * filename, struct utimbuf __user * times) goto dput_and_out; if (current->fsuid != inode->i_uid && - (error = permission(inode,MAY_WRITE,&nd)) != 0) + (error = vfs_permission(&nd, MAY_WRITE)) != 0) goto dput_and_out; } down(&inode->i_sem); @@ -447,7 +447,7 @@ long do_utimes(char __user * filename, struct timeval * times) goto dput_and_out; if (current->fsuid != inode->i_uid && - (error = permission(inode,MAY_WRITE,&nd)) != 0) + (error = vfs_permission(&nd, MAY_WRITE)) != 0) goto dput_and_out; } down(&inode->i_sem); @@ -506,7 +506,7 @@ asmlinkage long sys_access(const char __user * filename, int mode) res = __user_walk(filename, LOOKUP_FOLLOW|LOOKUP_ACCESS, &nd); if (!res) { - res = permission(nd.dentry->d_inode, mode, &nd); + res = vfs_permission(&nd, mode); /* SuS v2 requires we report a read only fs too */ if(!res && (mode & S_IWOTH) && IS_RDONLY(nd.dentry->d_inode) && !special_file(nd.dentry->d_inode->i_mode)) @@ -530,7 +530,7 @@ asmlinkage long sys_chdir(const char __user * filename) if (error) goto out; - error = permission(nd.dentry->d_inode,MAY_EXEC,&nd); + error = vfs_permission(&nd, MAY_EXEC); if (error) goto dput_and_out; @@ -581,7 +581,7 @@ asmlinkage long sys_chroot(const char __user * filename) if (error) goto out; - error = permission(nd.dentry->d_inode,MAY_EXEC,&nd); + error = vfs_permission(&nd, MAY_EXEC); if (error) goto dput_and_out; -- cgit From 8c744fb83da0771afa04695028e3550b798dad90 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 8 Nov 2005 21:35:04 -0800 Subject: [PATCH] add a file_permission helper A few more callers of permission() just want to check for a different access pattern on an already open file. This patch adds a wrapper for permission() that takes a file in preparation of per-mount read-only support and to clean up the callers a little. The helper is not intended for new code, everything without the interface set in stone should use vfs_permission() Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/open.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/open.c') diff --git a/fs/open.c b/fs/open.c index baffc084580d..f53a5b9ffb7d 100644 --- a/fs/open.c +++ b/fs/open.c @@ -563,7 +563,7 @@ asmlinkage long sys_fchdir(unsigned int fd) if (!S_ISDIR(inode->i_mode)) goto out_putf; - error = permission(inode, MAY_EXEC, NULL); + error = file_permission(file, MAY_EXEC); if (!error) set_fs_pwd(current->fs, mnt, dentry); out_putf: -- cgit