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Diffstat (limited to 'fs/namei.c')
-rw-r--r--fs/namei.c121
1 files changed, 71 insertions, 50 deletions
diff --git a/fs/namei.c b/fs/namei.c
index 921ae32dbc80..a66ed5a1622a 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -39,6 +39,7 @@
#include <linux/bitops.h>
#include <linux/init_task.h>
#include <linux/uaccess.h>
+#include <linux/build_bug.h>
#include "internal.h"
#include "mount.h"
@@ -130,6 +131,7 @@ getname_flags(const char __user *filename, int flags, int *empty)
struct filename *result;
char *kname;
int len;
+ BUILD_BUG_ON(offsetof(struct filename, iname) % sizeof(long) != 0);
result = audit_reusename(filename);
if (result)
@@ -559,9 +561,10 @@ static int __nd_alloc_stack(struct nameidata *nd)
static bool path_connected(const struct path *path)
{
struct vfsmount *mnt = path->mnt;
+ struct super_block *sb = mnt->mnt_sb;
- /* Only bind mounts can have disconnected paths */
- if (mnt->mnt_root == mnt->mnt_sb->s_root)
+ /* Bind mounts and multi-root filesystems can have disconnected paths */
+ if (!(sb->s_iflags & SB_I_MULTIROOT) && (mnt->mnt_root == sb->s_root))
return true;
return is_subdir(path->dentry, mnt->mnt_root);
@@ -926,7 +929,8 @@ static inline int may_follow_link(struct nameidata *nd)
if (nd->flags & LOOKUP_RCU)
return -ECHILD;
- audit_log_link_denied("follow_link", &nd->stack[0].link);
+ audit_inode(nd->name, nd->stack[0].link.dentry, 0);
+ audit_log_link_denied("follow_link");
return -EACCES;
}
@@ -992,7 +996,7 @@ static int may_linkat(struct path *link)
if (safe_hardlink_source(inode) || inode_owner_or_capable(inode))
return 0;
- audit_log_link_denied("linkat", link);
+ audit_log_link_denied("linkat");
return -EPERM;
}
@@ -1473,43 +1477,36 @@ static struct dentry *lookup_dcache(const struct qstr *name,
}
/*
- * Call i_op->lookup on the dentry. The dentry must be negative and
- * unhashed.
- *
- * dir->d_inode->i_mutex must be held
+ * Parent directory has inode locked exclusive. This is one
+ * and only case when ->lookup() gets called on non in-lookup
+ * dentries - as the matter of fact, this only gets called
+ * when directory is guaranteed to have no in-lookup children
+ * at all.
*/
-static struct dentry *lookup_real(struct inode *dir, struct dentry *dentry,
- unsigned int flags)
-{
- struct dentry *old;
-
- /* Don't create child dentry for a dead directory. */
- if (unlikely(IS_DEADDIR(dir))) {
- dput(dentry);
- return ERR_PTR(-ENOENT);
- }
-
- old = dir->i_op->lookup(dir, dentry, flags);
- if (unlikely(old)) {
- dput(dentry);
- dentry = old;
- }
- return dentry;
-}
-
static struct dentry *__lookup_hash(const struct qstr *name,
struct dentry *base, unsigned int flags)
{
struct dentry *dentry = lookup_dcache(name, base, flags);
+ struct dentry *old;
+ struct inode *dir = base->d_inode;
if (dentry)
return dentry;
+ /* Don't create child dentry for a dead directory. */
+ if (unlikely(IS_DEADDIR(dir)))
+ return ERR_PTR(-ENOENT);
+
dentry = d_alloc(base, name);
if (unlikely(!dentry))
return ERR_PTR(-ENOMEM);
- return lookup_real(base->d_inode, dentry, flags);
+ old = dir->i_op->lookup(dir, dentry, flags);
+ if (unlikely(old)) {
+ dput(dentry);
+ dentry = old;
+ }
+ return dentry;
}
static int lookup_fast(struct nameidata *nd,
@@ -3380,9 +3377,7 @@ finish_open_created:
goto out;
*opened |= FILE_OPENED;
opened:
- error = open_check_o_direct(file);
- if (!error)
- error = ima_file_check(file, op->acc_mode, *opened);
+ error = ima_file_check(file, op->acc_mode, *opened);
if (!error && will_truncate)
error = handle_truncate(file);
out:
@@ -3462,9 +3457,6 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags,
error = finish_open(file, child, NULL, opened);
if (error)
goto out2;
- error = open_check_o_direct(file);
- if (error)
- fput(file);
out2:
mnt_drop_write(path.mnt);
out:
@@ -3728,8 +3720,8 @@ static int may_mknod(umode_t mode)
}
}
-SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
- unsigned, dev)
+long do_mknodat(int dfd, const char __user *filename, umode_t mode,
+ unsigned int dev)
{
struct dentry *dentry;
struct path path;
@@ -3772,9 +3764,15 @@ out:
return error;
}
+SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
+ unsigned int, dev)
+{
+ return do_mknodat(dfd, filename, mode, dev);
+}
+
SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, dev)
{
- return sys_mknodat(AT_FDCWD, filename, mode, dev);
+ return do_mknodat(AT_FDCWD, filename, mode, dev);
}
int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
@@ -3803,7 +3801,7 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
}
EXPORT_SYMBOL(vfs_mkdir);
-SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
+long do_mkdirat(int dfd, const char __user *pathname, umode_t mode)
{
struct dentry *dentry;
struct path path;
@@ -3828,9 +3826,14 @@ retry:
return error;
}
+SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
+{
+ return do_mkdirat(dfd, pathname, mode);
+}
+
SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode)
{
- return sys_mkdirat(AT_FDCWD, pathname, mode);
+ return do_mkdirat(AT_FDCWD, pathname, mode);
}
int vfs_rmdir(struct inode *dir, struct dentry *dentry)
@@ -3872,7 +3875,7 @@ out:
}
EXPORT_SYMBOL(vfs_rmdir);
-static long do_rmdir(int dfd, const char __user *pathname)
+long do_rmdir(int dfd, const char __user *pathname)
{
int error = 0;
struct filename *name;
@@ -4108,8 +4111,8 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
}
EXPORT_SYMBOL(vfs_symlink);
-SYSCALL_DEFINE3(symlinkat, const char __user *, oldname,
- int, newdfd, const char __user *, newname)
+long do_symlinkat(const char __user *oldname, int newdfd,
+ const char __user *newname)
{
int error;
struct filename *from;
@@ -4139,9 +4142,15 @@ out_putname:
return error;
}
+SYSCALL_DEFINE3(symlinkat, const char __user *, oldname,
+ int, newdfd, const char __user *, newname)
+{
+ return do_symlinkat(oldname, newdfd, newname);
+}
+
SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newname)
{
- return sys_symlinkat(oldname, AT_FDCWD, newname);
+ return do_symlinkat(oldname, AT_FDCWD, newname);
}
/**
@@ -4233,8 +4242,8 @@ EXPORT_SYMBOL(vfs_link);
* with linux 2.0, and to avoid hard-linking to directories
* and other special files. --ADM
*/
-SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname,
- int, newdfd, const char __user *, newname, int, flags)
+int do_linkat(int olddfd, const char __user *oldname, int newdfd,
+ const char __user *newname, int flags)
{
struct dentry *new_dentry;
struct path old_path, new_path;
@@ -4298,9 +4307,15 @@ out:
return error;
}
+SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname,
+ int, newdfd, const char __user *, newname, int, flags)
+{
+ return do_linkat(olddfd, oldname, newdfd, newname, flags);
+}
+
SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname)
{
- return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
+ return do_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
}
/**
@@ -4478,8 +4493,8 @@ out:
}
EXPORT_SYMBOL(vfs_rename);
-SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname,
- int, newdfd, const char __user *, newname, unsigned int, flags)
+static int do_renameat2(int olddfd, const char __user *oldname, int newdfd,
+ const char __user *newname, unsigned int flags)
{
struct dentry *old_dentry, *new_dentry;
struct dentry *trap;
@@ -4621,15 +4636,21 @@ exit:
return error;
}
+SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname,
+ int, newdfd, const char __user *, newname, unsigned int, flags)
+{
+ return do_renameat2(olddfd, oldname, newdfd, newname, flags);
+}
+
SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
int, newdfd, const char __user *, newname)
{
- return sys_renameat2(olddfd, oldname, newdfd, newname, 0);
+ return do_renameat2(olddfd, oldname, newdfd, newname, 0);
}
SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname)
{
- return sys_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
+ return do_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
}
int vfs_whiteout(struct inode *dir, struct dentry *dentry)
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-17 15:30:53 +0300