From: Gabriel Ivăncescu gabrielopcode@gmail.com
Based on code and suggestions by Jinoh Kang.
Signed-off-by: Gabriel Ivăncescu gabrielopcode@gmail.com --- dlls/kernel32/tests/file.c | 2 - server/fd.c | 141 ++++++++++++++++++++++++++++++++++++- 2 files changed, 140 insertions(+), 3 deletions(-)
diff --git a/dlls/kernel32/tests/file.c b/dlls/kernel32/tests/file.c index 378c3eb12a0..621293f8a69 100644 --- a/dlls/kernel32/tests/file.c +++ b/dlls/kernel32/tests/file.c @@ -2182,9 +2182,7 @@ static void test_MoveFileA(void) } FindClose(hfind); ret = GetFileAttributesA(source); - todo_wine ok(ret == INVALID_FILE_ATTRIBUTES && GetLastError() == ERROR_FILE_NOT_FOUND, "GetFileAttributesA: error %ld\n", GetLastError()); - if(ret != INVALID_FILE_ATTRIBUTES) DeleteFileA(source);
/* test renaming a regular file to a name with trailing slash */ lstrcpyA(source, dest); diff --git a/server/fd.c b/server/fd.c index 911fa4931c2..a090f3e83b9 100644 --- a/server/fd.c +++ b/server/fd.c @@ -2535,6 +2535,144 @@ static void set_fd_disposition( struct fd *fd, unsigned int flags ) ((fd->options & FILE_DELETE_ON_CLOSE) ? FILE_DISPOSITION_DELETE : 0); }
+/* rename the same file, dealing with casefolding and possibly different hardlinks to it */ +static void rename_same_file( const char *src, const char *dst, int is_dir ) +{ + static const char tmpname_fmt[] = ".wine-rename-tmp-%08x"; + static unsigned tmp_value; + + char *dirname, tmpname[sizeof(tmpname_fmt) + 4 /* remaining of %08x */]; + int dirfd, undo_tmp_rename = 0, res = 0; + const char *srcname, *dstname; + struct stat st, st2; + unsigned i; + + if (!strcmp( src, "/" ) || !strcmp( dst, "/" )) + { + set_error( STATUS_ACCESS_DENIED ); + return; + } + + /* first, check the directories they reside in */ + dstname = strrchr( dst, '/' ) + 1; + if (!(dirname = memdup( dst, dstname - dst ))) + return; + dirname[dstname - dst - 1] = '\0'; + if ((res = stat( dirname, &st ))) + file_set_error(); + free( dirname ); + if (res) + return; + + srcname = strrchr( src, '/' ) + 1; + if (!(dirname = memdup( src, srcname - src ))) + return; + dirname[srcname - src - 1] = '\0'; + if ((dirfd = open( dirname, O_RDONLY | O_NONBLOCK )) == -1) + file_set_error(); + free( dirname ); + if (dirfd == -1) + return; + + if (fstat( dirfd, &st2 )) + { + file_set_error(); + goto ret; + } + + /* if different directories, it must be a hardlink, so simply remove the source */ + if (st.st_ino != st2.st_ino || st.st_dev != st2.st_dev) + { + if (unlinkat( dirfd, srcname, 0 )) + file_set_error(); + goto ret; + } + + /* same dentry means a no-op */ + if (!strcmp( srcname, dstname )) goto ret; + + /* This is more complicated now, because in case of a casefold (+F) directory, the destination may very well be the same dentry, + * even if the name doesn't match (if it differs just by case), in which case unlinking it is wrong and can be dangerous. Instead, + * we first rename the source to a temporary filename in the same directory. If this is a casefold dir, this will also remove the + * destination, otherwise the destination still exists. We then create a hardlink from the destination to our temporary name, and + * finally, unlink the temporary. This still works if the directory is case sensitive, so it's not a problem in either case. */ + tmp_value += (current_time >> 16) + current_time; + for (i = 0; i < 0x8000; i++, tmp_value += 7777) + { + snprintf( tmpname, sizeof(tmpname), tmpname_fmt, tmp_value ); + + /* create an empty file or directory to avoid TOCTTOU */ + if (!is_dir) + { + int fd = openat( dirfd, tmpname, O_CREAT | O_EXCL, 0777 ); + if (fd == -1) + { + if (errno == EEXIST) continue; + file_set_error(); + goto ret; + } + close( fd ); + } + else if (mkdirat( dirfd, tmpname, 0777 )) + { + if (errno == EEXIST) continue; + file_set_error(); + goto ret; + } + + if (renameat( dirfd, srcname, dirfd, tmpname )) + { + file_set_error(); + unlinkat( dirfd, tmpname, is_dir ? AT_REMOVEDIR : 0 ); + goto ret; + } + + break; + } + if (i >= 0x8000) + { + set_error( STATUS_UNSUCCESSFUL ); + goto ret; + } + + undo_tmp_rename = 1; + + /* directories can't have hardlinks */ + if (!is_dir) + { + /* we can't just do rename(2) here; renaming a file to its hardlink is no-op */ + if (!linkat( dirfd, tmpname, dirfd, dstname, 0 ) || errno == EEXIST) + { + undo_tmp_rename = 0; + + if (unlinkat( dirfd, tmpname, 0 )) + file_set_error(); + goto ret; + } + + if (errno != EPERM && errno != EOPNOTSUPP) + { + file_set_error(); + goto ret; + } + + /* filesystem doesn't support hardlinks, fall back to renaming (same as directories) */ + } + + if (renameat( dirfd, tmpname, dirfd, dstname )) + file_set_error(); + else + undo_tmp_rename = 0; + +ret: + if (undo_tmp_rename) + { + /* revert the temporary rename */ + renameat( dirfd, tmpname, dirfd, srcname ); + } + close( dirfd ); +} + /* set new name for the fd */ static void set_fd_name( struct fd *fd, struct fd *root, const char *nameptr, data_size_t len, struct unicode_str nt_name, int create_link, unsigned int flags ) @@ -2592,7 +2730,8 @@ static void set_fd_name( struct fd *fd, struct fd *root, const char *nameptr, da { if (!fstat( fd->unix_fd, &st2 ) && st.st_ino == st2.st_ino && st.st_dev == st2.st_dev) { - if (create_link && !replace) set_error( STATUS_OBJECT_NAME_COLLISION ); + if (!create_link) rename_same_file( fd->unix_name, name, S_ISDIR( st.st_mode ) ); + else if (!replace) set_error( STATUS_OBJECT_NAME_COLLISION ); free( name ); return; }