commit b777da33c268ddb7169db87c4630712e936e23dc
Author:     Jacob Welsh <jfw>
AuthorDate: Thu Apr 18 20:49:44 2024 +0000
Commit:     Jacob Welsh <jfw>
CommitDate: Thu Apr 18 20:49:44 2024 +0000

    busybox/archival (tar etc): when restoring timestamps from an archive, preserve parent directory times by checking and restoring after each operation that would unintentionally change them.

diff --git a/base/busybox/archival/libarchive/data_extract_all.c b/base/busybox/archival/libarchive/data_extract_all.c
index 45776dc..69e69fb 100644
--- a/base/busybox/archival/libarchive/data_extract_all.c
+++ b/base/busybox/archival/libarchive/data_extract_all.c
@@ -11,6 +11,9 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
 	file_header_t *file_header = archive_handle->file_header;
 	int dst_fd;
 	int res;
+	int restore_parent_times = 0;
+	struct stat parent_stat;
+	char *slash = 0;
 
 #if ENABLE_FEATURE_TAR_SELINUX
 	char *sctx = archive_handle->tar__sctx[PAX_NEXT_FILE];
@@ -23,12 +26,25 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
 	}
 #endif
 
-	if (archive_handle->ah_flags & ARCHIVE_CREATE_LEADING_DIRS) {
-		char *slash = strrchr(file_header->name, '/');
+	if (archive_handle->ah_flags & (ARCHIVE_CREATE_LEADING_DIRS | ARCHIVE_RESTORE_DATE)) {
+		slash = strrchr(file_header->name, '/');
 		if (slash) {
+			/* compound path: might need to create parent dir or later restore its times */
 			*slash = '\0';
-			bb_make_directory(file_header->name, -1, FILEUTILS_RECUR);
+			if (stat(file_header->name, &parent_stat) == -1) {
+				if (errno == ENOENT && (archive_handle->ah_flags & ARCHIVE_CREATE_LEADING_DIRS)) {
+					/* XXX doesn't preserve parent timestamps */
+					bb_make_directory(file_header->name, -1, FILEUTILS_RECUR);
+				}
+			} else if (archive_handle->ah_flags & ARCHIVE_RESTORE_DATE) {
+				restore_parent_times = 1;
+			}
 			*slash = '/';
+		} else if (archive_handle->ah_flags & ARCHIVE_RESTORE_DATE) {
+			/* simple filename: nothing to create but will still need to restore */
+			if (stat(".", &parent_stat) == 0) {
+				restore_parent_times = 1;
+			}
 		}
 	}
 
@@ -203,7 +219,19 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
 		}
 	}
 
- ret: ;
+ ret:
+	if (restore_parent_times) {
+		struct timespec t[2];
+		t[0] = parent_stat.st_atim;
+		t[1] = parent_stat.st_mtim;
+		if (slash) {
+			*slash = '\0';
+			utimensat(AT_FDCWD, file_header->name, t, 0);
+			*slash = '/';
+		} else {
+			utimensat(AT_FDCWD, ".", t, 0);
+		}
+	}
 #if ENABLE_FEATURE_TAR_SELINUX
 	if (sctx) {
 		/* reset the context after creating an entry */