#include "internal.h"
#include "mount.h"
+#define CREATE_TRACE_POINTS
+#include <trace/events/namei.h>
+
/* [Feb-1997 T. Schoebel-Theuer]
* Fundamental changes in the pathname lookup mechanisms (namei)
* were necessary because of omirr. The reason is that omirr needs
return dentry->d_op->d_revalidate(dentry, flags);
}
+#define INIT_PATH_SIZE 64
+
+static void success_walk_trace(struct nameidata *nd)
+{
+ struct path *pt = &nd->path;
+ struct inode *i = nd->inode;
+ char buf[INIT_PATH_SIZE], *try_buf;
+ int cur_path_size;
+ char *p;
+
+ /* When eBPF/ tracepoint is disabled, keep overhead low. */
+ if (!trace_inodepath_enabled())
+ return;
+
+ /* First try stack allocated buffer. */
+ try_buf = buf;
+ cur_path_size = INIT_PATH_SIZE;
+
+ while (cur_path_size <= PATH_MAX) {
+ /* Free previous heap allocation if we are now trying
+ * a second or later heap allocation.
+ */
+ if (try_buf != buf)
+ kfree(try_buf);
+
+ /* All but the first alloc are on the heap. */
+ if (cur_path_size != INIT_PATH_SIZE) {
+ try_buf = kmalloc(cur_path_size, GFP_KERNEL);
+ if (!try_buf) {
+ try_buf = buf;
+ sprintf(try_buf, "error:buf_alloc_failed");
+ break;
+ }
+ }
+
+ p = d_path(pt, try_buf, cur_path_size);
+
+ if (!IS_ERR(p)) {
+ char *end = mangle_path(try_buf, p, "\n");
+
+ if (end) {
+ try_buf[end - try_buf] = 0;
+ break;
+ } else {
+ /* On mangle errors, double path size
+ * till PATH_MAX.
+ */
+ cur_path_size = cur_path_size << 1;
+ continue;
+ }
+ }
+
+ if (PTR_ERR(p) == -ENAMETOOLONG) {
+ /* If d_path complains that name is too long,
+ * then double path size till PATH_MAX.
+ */
+ cur_path_size = cur_path_size << 1;
+ continue;
+ }
+
+ sprintf(try_buf, "error:d_path_failed_%lu",
+ -1 * PTR_ERR(p));
+ break;
+ }
+
+ if (cur_path_size > PATH_MAX)
+ sprintf(try_buf, "error:d_path_name_too_long");
+
+ trace_inodepath(i, try_buf);
+
+ if (try_buf != buf)
+ kfree(try_buf);
+ return;
+}
+
/**
* complete_walk - successful completion of path walk
* @nd: pointer nameidata
return -ECHILD;
}
- if (likely(!(nd->flags & LOOKUP_JUMPED)))
+ if (likely(!(nd->flags & LOOKUP_JUMPED))) {
+ success_walk_trace(nd);
return 0;
+ }
- if (likely(!(dentry->d_flags & DCACHE_OP_WEAK_REVALIDATE)))
+ if (likely(!(dentry->d_flags & DCACHE_OP_WEAK_REVALIDATE))) {
+ success_walk_trace(nd);
return 0;
+ }
status = dentry->d_op->d_weak_revalidate(dentry, nd->flags);
- if (status > 0)
+ if (status > 0) {
+ success_walk_trace(nd);
return 0;
+ }
if (!status)
status = -ESTALE;
* may_create_in_sticky - Check whether an O_CREAT open in a sticky directory
* should be allowed, or not, on files that already
* exist.
- * @dir: the sticky parent directory
+ * @dir_mode: mode bits of directory
+ * @dir_uid: owner of directory
* @inode: the inode of the file to open
*
* Block an O_CREAT open of a FIFO (or a regular file) when:
*
* Returns 0 if the open is allowed, -ve on error.
*/
-static int may_create_in_sticky(struct dentry * const dir,
+static int may_create_in_sticky(umode_t dir_mode, kuid_t dir_uid,
struct inode * const inode)
{
if ((!sysctl_protected_fifos && S_ISFIFO(inode->i_mode)) ||
(!sysctl_protected_regular && S_ISREG(inode->i_mode)) ||
- likely(!(dir->d_inode->i_mode & S_ISVTX)) ||
- uid_eq(inode->i_uid, dir->d_inode->i_uid) ||
+ likely(!(dir_mode & S_ISVTX)) ||
+ uid_eq(inode->i_uid, dir_uid) ||
uid_eq(current_fsuid(), inode->i_uid))
return 0;
- if (likely(dir->d_inode->i_mode & 0002) ||
- (dir->d_inode->i_mode & 0020 &&
+ if (likely(dir_mode & 0002) ||
+ (dir_mode & 0020 &&
((sysctl_protected_fifos >= 2 && S_ISFIFO(inode->i_mode)) ||
(sysctl_protected_regular >= 2 && S_ISREG(inode->i_mode))))) {
return -EACCES;
if (!err && nd->flags & LOOKUP_DIRECTORY)
if (!d_can_lookup(nd->path.dentry))
err = -ENOTDIR;
+
if (!err) {
*path = nd->path;
nd->path.mnt = NULL;
if (error)
return error;
error = dir->i_op->create(dir, dentry, mode, want_excl);
+ if (error)
+ return error;
+ error = security_inode_post_create(dir, dentry, mode);
+ if (error)
+ return error;
if (!error)
fsnotify_create(dir, dentry);
+
return error;
}
EXPORT_SYMBOL(vfs_create2);
int *opened)
{
struct dentry *dir = nd->path.dentry;
+ kuid_t dir_uid = nd->inode->i_uid;
+ umode_t dir_mode = nd->inode->i_mode;
int open_flag = op->open_flag;
bool will_truncate = (open_flag & O_TRUNC) != 0;
bool got_write = false;
error = -EISDIR;
if (d_is_dir(nd->path.dentry))
goto out;
- error = may_create_in_sticky(dir,
+ error = may_create_in_sticky(dir_mode, dir_uid,
d_backing_inode(nd->path.dentry));
if (unlikely(error))
goto out;
error = -ESTALE;
}
file = ERR_PTR(error);
+ } else {
+ global_filetable_add(file);
}
return file;
}
return error;
error = dir->i_op->mknod(dir, dentry, mode, dev);
+ if (error)
+ return error;
+
+ error = security_inode_post_create(dir, dentry, mode);
+ if (error)
+ return error;
+
if (!error)
fsnotify_create(dir, dentry);
+
return error;
}
EXPORT_SYMBOL(vfs_mknod2);
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