Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 305 insertions, 0 deletions

diff --git a/src/VBox/Additions/linux/sharedfolders/lnkops.c b/src/VBox/Additions/linux/sharedfolders/lnkops.c
new file mode 100644
index 00000000..0d37a155
--- /dev/null
+++ b/src/VBox/Additions/linux/sharedfolders/lnkops.c
@@ -0,0 +1,305 @@
+/* $Id: lnkops.c $ */
+/** @file
+ * vboxsf - VBox Linux Shared Folders VFS, operations for symbolic links.
+ */
+
+/*
+ * Copyright (C) 2010-2023 Oracle and/or its affiliates.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#include "vfsmod.h"
+
+
+/**
+ * Converts error codes as best we can.
+ */
+DECLINLINE(int) vbsf_convert_symlink_error(int vrc)
+{
+    if (   vrc == VERR_IS_A_DIRECTORY
+        || vrc == VERR_IS_A_FIFO
+        || vrc == VERR_IS_A_FILE
+        || vrc == VERR_IS_A_BLOCK_DEVICE
+        || vrc == VERR_IS_A_CHAR_DEVICE
+        || vrc == VERR_IS_A_SOCKET
+        || vrc == VERR_NOT_SYMLINK)
+        return -EINVAL;
+    if (vrc == VERR_PATH_NOT_FOUND)
+        return -ENOTDIR;
+    if (vrc == VERR_FILE_NOT_FOUND)
+        return -ENOENT;
+    return -EPROTO;
+}
+
+
+/**
+ * Does the NLS conversion of the symlink target.
+ */
+static int vbsf_symlink_nls_convert_slow(struct vbsf_super_info *pSuperInfo, char *pszTarget, size_t cbTargetBuf)
+{
+    int          rc;
+    size_t const cchUtf8 = RTStrNLen(pszTarget, cbTargetBuf);
+    if (cchUtf8 < cbTargetBuf) {
+        /*
+         * If the target is short and there is a lot of space left in the target
+         * buffer (typically PAGE_SIZE in size), we move the  input to the end
+         * instead of allocating a temporary buffer for it.  This works because
+         * there shouldn't be anything that is more than 8x worse than UTF-8
+         * when it comes to efficiency.
+         */
+        char  *pszFree = NULL;
+        char  *pszUtf8;
+        if (cchUtf8 - 1 <= cbTargetBuf / 8) {
+            pszUtf8 = &pszTarget[cbTargetBuf - cchUtf8 - 1];
+            cbTargetBuf -= cchUtf8 - 1;
+        } else {
+            pszFree = pszUtf8 = kmalloc(cchUtf8 + 1, GFP_KERNEL);
+            if (RT_UNLIKELY(!pszUtf8)) {
+                LogRelMax(50, ("vbsf_symlink_nls_convert_slow: failed to allocate %u bytes\n", cchUtf8 + 1));
+                return -ENOMEM;
+            }
+        }
+        memcpy(pszUtf8, pszTarget, cchUtf8);
+        pszUtf8[cchUtf8] = '\0';
+
+        rc = vbsf_nlscpy(pSuperInfo, pszTarget, cbTargetBuf, pszUtf8, cchUtf8);
+        if (pszFree)
+            kfree(pszFree);
+    } else {
+        SFLOGFLOW(("vbsf_symlink_nls_convert_slow: Impossible! Unterminated target!\n"));
+        rc = -ENAMETOOLONG;
+    }
+    return rc;
+}
+
+
+/**
+ * Does NLS conversion if needed.
+ */
+DECLINLINE(int) vbsf_symlink_nls_convert(struct vbsf_super_info *pSuperInfo, char *pszTarget, size_t cbTargetBuf)
+{
+    if (pSuperInfo->fNlsIsUtf8)
+        return 0;
+    return vbsf_symlink_nls_convert_slow(pSuperInfo, pszTarget, cbTargetBuf);
+}
+
+#if RTLNX_VER_MIN(4,5,0)
+
+/**
+ * Get symbolic link.
+ */
+static const char *vbsf_get_link(struct dentry *dentry, struct inode *inode, struct delayed_call *done)
+{
+    char *pszTarget;
+    if (dentry) {
+        pszTarget = (char *)kzalloc(PAGE_SIZE, GFP_KERNEL);
+        if (pszTarget) {
+            struct vbsf_super_info *pSuperInfo = VBSF_GET_SUPER_INFO(inode->i_sb);
+            struct vbsf_inode_info *sf_i       = VBSF_GET_INODE_INFO(inode);
+            int rc = VbglR0SfHostReqReadLinkContigSimple(pSuperInfo->map.root, sf_i->path->String.ach, sf_i->path->u16Length,
+                                                         pszTarget, virt_to_phys(pszTarget), RT_MIN(PATH_MAX, PAGE_SIZE - 1));
+            if (RT_SUCCESS(rc)) {
+                pszTarget[PAGE_SIZE - 1] = '\0';
+                SFLOGFLOW(("vbsf_get_link: %s -> %s\n", sf_i->path->String.ach, pszTarget));
+                rc = vbsf_symlink_nls_convert(pSuperInfo, pszTarget, PAGE_SIZE);
+                if (rc == 0) {
+                    vbsf_dentry_chain_increase_ttl(dentry);
+                    set_delayed_call(done, kfree_link, pszTarget);
+                    return pszTarget;
+                }
+            } else {
+                SFLOGFLOW(("vbsf_get_link: VbglR0SfHostReqReadLinkContigSimple failed on '%s': %Rrc\n",
+                           sf_i->path->String.ach, rc));
+            }
+            kfree(pszTarget);
+            pszTarget = ERR_PTR(vbsf_convert_symlink_error(rc));
+        } else
+            pszTarget = ERR_PTR(-ENOMEM);
+    } else
+        pszTarget = ERR_PTR(-ECHILD);
+    return pszTarget;
+}
+
+#else /* < 4.5 */
+
+# if RTLNX_VER_MAX(2,6,8)
+/**
+ * Reads the link into the given buffer.
+ */
+static int vbsf_readlink(struct dentry *dentry, char *buffer, int len)
+{
+    int   rc;
+    char *pszTarget = (char *)get_zeroed_page(GFP_KERNEL);
+    if (pszTarget) {
+        struct inode           *inode = dentry->d_inode;
+        struct vbsf_super_info *pSuperInfo = VBSF_GET_SUPER_INFO(inode->i_sb);
+        struct vbsf_inode_info *sf_i       = VBSF_GET_INODE_INFO(inode);
+        rc = VbglR0SfHostReqReadLinkContigSimple(pSuperInfo->map.root, sf_i->path->String.ach, sf_i->path->u16Length,
+                                                 pszTarget, virt_to_phys(pszTarget), RT_MIN(PATH_MAX, PAGE_SIZE - 1));
+        if (RT_SUCCESS(rc)) {
+            pszTarget[PAGE_SIZE - 1] = '\0';
+            SFLOGFLOW(("vbsf_readlink: %s -> %*s\n", sf_i->path->String.ach, pszTarget));
+            rc = vbsf_symlink_nls_convert(pSuperInfo, pszTarget, PAGE_SIZE);
+            if (rc == 0) {
+                vbsf_dentry_chain_increase_ttl(dentry);
+                rc = vfs_readlink(dentry, buffer, len, pszTarget);
+            }
+        } else {
+            SFLOGFLOW(("vbsf_readlink: VbglR0SfHostReqReadLinkContigSimple failed on '%s': %Rrc\n", sf_i->path->String.ach, rc));
+            rc = vbsf_convert_symlink_error(rc);
+        }
+        free_page((unsigned long)pszTarget);
+    } else
+        rc = -ENOMEM;
+    return rc;
+}
+# endif /* < 2.6.8 */
+
+/**
+ * Follow link in dentry.
+ */
+# if RTLNX_VER_MIN(4,2,0)
+static const char *vbsf_follow_link(struct dentry *dentry, void **cookie)
+# elif RTLNX_VER_MIN(2,6,13)
+static void       *vbsf_follow_link(struct dentry *dentry, struct nameidata *nd)
+# else
+static int         vbsf_follow_link(struct dentry *dentry, struct nameidata *nd)
+# endif
+{
+    int rc;
+    char *pszTarget = (char *)get_zeroed_page(GFP_KERNEL);
+    if (pszTarget) {
+        struct inode           *inode = dentry->d_inode;
+        struct vbsf_super_info *pSuperInfo = VBSF_GET_SUPER_INFO(inode->i_sb);
+        struct vbsf_inode_info *sf_i       = VBSF_GET_INODE_INFO(inode);
+
+        rc = VbglR0SfHostReqReadLinkContigSimple(pSuperInfo->map.root, sf_i->path->String.ach, sf_i->path->u16Length,
+                                                 pszTarget, virt_to_phys(pszTarget), RT_MIN(PATH_MAX, PAGE_SIZE - 1));
+        if (RT_SUCCESS(rc)) {
+            pszTarget[PAGE_SIZE - 1] = '\0';
+            SFLOGFLOW(("vbsf_follow_link: %s -> %s\n", sf_i->path->String.ach, pszTarget));
+            rc = vbsf_symlink_nls_convert(pSuperInfo, pszTarget, PAGE_SIZE);
+            if (rc == 0) {
+                /*
+                 * Succeeded.  For 2.6.8 and later the page gets associated
+                 * with the caller-cookie or nameidata structure and freed
+                 * later by vbsf_put_link().  On earlier kernels we have to
+                 * call vfs_follow_link() which will try continue the walking
+                 * using the buffer we pass it here.
+                 */
+                vbsf_dentry_chain_increase_ttl(dentry);
+# if RTLNX_VER_MIN(4,2,0)
+                *cookie = pszTarget;
+                return pszTarget;
+# elif RTLNX_VER_MIN(2,6,8)
+                nd_set_link(nd, pszTarget);
+#  if RTLNX_VER_MIN(2,6,13)
+                return NULL;
+#  else
+                return 0;
+#  endif
+# else /* < 2.6.8 */
+                rc = vfs_follow_link(nd, pszTarget);
+                free_page((unsigned long)pszTarget);
+                return rc;
+# endif
+            }
+
+            /*
+             * Failed.
+             */
+        } else {
+            LogFunc(("VbglR0SfReadLink failed, caller=%s, rc=%Rrc\n", __func__, rc));
+            rc = vbsf_convert_symlink_error(rc);
+        }
+        free_page((unsigned long)pszTarget);
+    } else {
+        rc = -ENOMEM;
+    }
+# if RTLNX_VER_MIN(4,2,0)
+    *cookie = ERR_PTR(rc);
+    return (const char *)ERR_PTR(rc);
+# elif RTLNX_VER_MIN(2,6,8)
+    nd_set_link(nd, (char *)ERR_PTR(rc));
+#  if RTLNX_VER_MIN(2,6,13)
+    return NULL;
+#  else
+    return 0;
+#  endif
+# else  /* < 2.6.8 */
+    return rc;
+# endif /* < 2.6.8 */
+}
+
+# if RTLNX_VER_MIN(2,6,8)
+/**
+ * For freeing target link buffer allocated by vbsf_follow_link.
+ *
+ * For kernels before 2.6.8 memory isn't being kept around.
+ */
+#  if RTLNX_VER_MIN(4,2,0)
+static void vbsf_put_link(struct inode *inode, void *cookie)
+#  elif RTLNX_VER_MIN(2,6,13)
+static void vbsf_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
+#  else
+static void vbsf_put_link(struct dentry *dentry, struct nameidata *nd)
+#  endif
+{
+#  if RTLNX_VER_MIN(2,6,13)
+    char *page = cookie;
+#  else
+    char *page = nd_get_link(nd);
+#  endif
+    SFLOGFLOW(("vbsf_put_link: page=%p\n", page));
+    if (!IS_ERR(page))
+        free_page((unsigned long)page);
+}
+# endif /* >= 2.6.8 */
+
+#endif /* < 4.5.0 */
+
+/**
+ * Symlink inode operations.
+ */
+struct inode_operations vbsf_lnk_iops = {
+#if RTLNX_VER_MAX(4,10,0)
+# if RTLNX_VER_MIN(2,6,8)
+    .readlink    = generic_readlink,
+# else
+    .readlink    = vbsf_readlink,
+# endif
+#endif
+#if RTLNX_VER_MIN(4,5,0)
+    .get_link    = vbsf_get_link
+#else
+    .follow_link = vbsf_follow_link,
+# if RTLNX_VER_MIN(2,6,8)
+    .put_link    = vbsf_put_link,
+# endif
+#endif
+};
+