[clang] [clang] Reject character devices in #embed for now (PR #135370)
Mariya Podchishchaeva via cfe-commits
cfe-commits at lists.llvm.org
Fri Apr 11 08:30:20 PDT 2025
https://github.com/Fznamznon updated https://github.com/llvm/llvm-project/pull/135370
>From 49e347a73709661fcf3a4805f38cfa2d78e3a196 Mon Sep 17 00:00:00 2001
From: "Podchishchaeva, Mariya" <mariya.podchishchaeva at intel.com>
Date: Fri, 11 Apr 2025 06:46:00 -0700
Subject: [PATCH 1/4] [clang] Reject character devices in #embed for now
See https://github.com/llvm/llvm-project/issues/126629 .
Right not they are not supported properly and support requires modifying
several layers of LLVM. For now simply reject them while proper support
is being developed to avoid potential security problems.
---
clang/include/clang/Basic/DiagnosticLexKinds.td | 2 ++
clang/include/clang/Basic/FileEntry.h | 6 ++++++
clang/lib/Basic/FileManager.cpp | 2 ++
clang/lib/Lex/PPDirectives.cpp | 6 ++++++
4 files changed, 16 insertions(+)
diff --git a/clang/include/clang/Basic/DiagnosticLexKinds.td b/clang/include/clang/Basic/DiagnosticLexKinds.td
index 912b8bd46e194..f29edfa835d42 100644
--- a/clang/include/clang/Basic/DiagnosticLexKinds.td
+++ b/clang/include/clang/Basic/DiagnosticLexKinds.td
@@ -458,6 +458,8 @@ def warn_compat_pp_embed_directive : Warning<
InGroup<CPre23Compat>, DefaultIgnore;
def err_pp_embed_dup_params : Error<
"cannot specify parameter '%0' twice in the same '#embed' directive">;
+def err_pp_embed_device_file : Error<
+ "device files are not yet supported by '#embed' directive">;
def ext_pp_extra_tokens_at_eol : ExtWarn<
"extra tokens at end of #%0 directive">, InGroup<ExtraTokens>;
diff --git a/clang/include/clang/Basic/FileEntry.h b/clang/include/clang/Basic/FileEntry.h
index da5ba90974293..c973ba38bdf7e 100644
--- a/clang/include/clang/Basic/FileEntry.h
+++ b/clang/include/clang/Basic/FileEntry.h
@@ -82,6 +82,7 @@ class FileEntryRef {
inline const llvm::sys::fs::UniqueID &getUniqueID() const;
inline time_t getModificationTime() const;
inline bool isNamedPipe() const;
+ inline bool isDeviceFile() const;
inline void closeFile() const;
/// Check if the underlying FileEntry is the same, intentially ignoring
@@ -316,6 +317,7 @@ class FileEntry {
llvm::sys::fs::UniqueID UniqueID;
unsigned UID = 0; // A unique (small) ID for the file.
bool IsNamedPipe = false;
+ bool IsDeviceFile = false;
/// The open file, if it is owned by the \p FileEntry.
mutable std::unique_ptr<llvm::vfs::File> File;
@@ -340,6 +342,7 @@ class FileEntry {
/// Check whether the file is a named pipe (and thus can't be opened by
/// the native FileManager methods).
bool isNamedPipe() const { return IsNamedPipe; }
+ bool isDeviceFile() const { return IsDeviceFile; }
void closeFile() const;
};
@@ -357,6 +360,9 @@ time_t FileEntryRef::getModificationTime() const {
}
bool FileEntryRef::isNamedPipe() const { return getFileEntry().isNamedPipe(); }
+bool FileEntryRef::isDeviceFile() const {
+ return getFileEntry().isDeviceFile();
+}
void FileEntryRef::closeFile() const { getFileEntry().closeFile(); }
diff --git a/clang/lib/Basic/FileManager.cpp b/clang/lib/Basic/FileManager.cpp
index ec84aad72e6be..86fe352df0461 100644
--- a/clang/lib/Basic/FileManager.cpp
+++ b/clang/lib/Basic/FileManager.cpp
@@ -330,6 +330,8 @@ llvm::Expected<FileEntryRef> FileManager::getFileRef(StringRef Filename,
UFE->UID = NextFileUID++;
UFE->UniqueID = Status.getUniqueID();
UFE->IsNamedPipe = Status.getType() == llvm::sys::fs::file_type::fifo_file;
+ UFE->IsDeviceFile =
+ Status.getType() == llvm::sys::fs::file_type::character_file;
UFE->File = std::move(F);
if (UFE->File) {
diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp
index d97a6e8d64f9c..318b8fdad2e04 100644
--- a/clang/lib/Lex/PPDirectives.cpp
+++ b/clang/lib/Lex/PPDirectives.cpp
@@ -4010,6 +4010,12 @@ void Preprocessor::HandleEmbedDirective(SourceLocation HashLoc, Token &EmbedTok,
Diag(FilenameTok, diag::err_pp_file_not_found) << Filename;
return;
}
+
+ if (MaybeFileRef->isDeviceFile()) {
+ Diag(FilenameTok, diag::err_pp_embed_device_file) << Filename;
+ return;
+ }
+
std::optional<llvm::MemoryBufferRef> MaybeFile =
getSourceManager().getMemoryBufferForFileOrNone(*MaybeFileRef);
if (!MaybeFile) {
>From a1e3d56f9b40ad6ceefbe41a53536fd5b64724ef Mon Sep 17 00:00:00 2001
From: "Podchishchaeva, Mariya" <mariya.podchishchaeva at intel.com>
Date: Fri, 11 Apr 2025 07:35:13 -0700
Subject: [PATCH 2/4] Pick up the test!
---
.../Preprocessor/embed-reject-device-files.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
create mode 100644 clang/test/Preprocessor/embed-reject-device-files.c
diff --git a/clang/test/Preprocessor/embed-reject-device-files.c b/clang/test/Preprocessor/embed-reject-device-files.c
new file mode 100644
index 0000000000000..4c9744ad86d44
--- /dev/null
+++ b/clang/test/Preprocessor/embed-reject-device-files.c
@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -std=c23 %s -fsyntax-only -verify
+// REQUIRES: system-linux
+
+
+int urandom[] = {
+#embed "/dev/urandom" //expected-error {{device files are not yet supported by '#embed' directive}}
+};
+int random[] = {
+#embed "/dev/random" //expected-error {{device files are not yet supported by '#embed' directive}}
+};
+int zero[] = {
+#embed "/dev/zero" //expected-error {{device files are not yet supported by '#embed' directive}}
+};
+int null[] = {
+#embed "/dev/null" //expected-error {{device files are not yet supported by '#embed' directive}}
+};
>From 27272fc28f4c780137b9a97760d68d6837af5ed2 Mon Sep 17 00:00:00 2001
From: "Podchishchaeva, Mariya" <mariya.podchishchaeva at intel.com>
Date: Fri, 11 Apr 2025 07:38:04 -0700
Subject: [PATCH 3/4] Add a release note
---
clang/docs/ReleaseNotes.rst | 3 +++
1 file changed, 3 insertions(+)
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 69c7369755c67..d82915b29ce54 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -387,6 +387,9 @@ Bug Fixes in This Version
#if 1 ? 1 : 999999999999999999999
#endif
+- ``#embed`` directive now diagnoses use of a non-character file (device file)
+ such as ``/dev/urandom`` as an error. This restriction may be relaxed in the
+ future. See (#GH126629).
Bug Fixes to Compiler Builtins
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>From 94ab4c3e2abd26098d57cd1c54d9540082a7f671 Mon Sep 17 00:00:00 2001
From: "Podchishchaeva, Mariya" <mariya.podchishchaeva at intel.com>
Date: Fri, 11 Apr 2025 08:29:48 -0700
Subject: [PATCH 4/4] Add win test
---
...ject-device-files.c => embed-reject-device-files-lin.c} | 0
clang/test/Preprocessor/embed-reject-device-files-win.c | 7 +++++++
2 files changed, 7 insertions(+)
rename clang/test/Preprocessor/{embed-reject-device-files.c => embed-reject-device-files-lin.c} (100%)
create mode 100644 clang/test/Preprocessor/embed-reject-device-files-win.c
diff --git a/clang/test/Preprocessor/embed-reject-device-files.c b/clang/test/Preprocessor/embed-reject-device-files-lin.c
similarity index 100%
rename from clang/test/Preprocessor/embed-reject-device-files.c
rename to clang/test/Preprocessor/embed-reject-device-files-lin.c
diff --git a/clang/test/Preprocessor/embed-reject-device-files-win.c b/clang/test/Preprocessor/embed-reject-device-files-win.c
new file mode 100644
index 0000000000000..640b59ab7535c
--- /dev/null
+++ b/clang/test/Preprocessor/embed-reject-device-files-win.c
@@ -0,0 +1,7 @@
+// RUN: %clang_cc1 -std=c23 %s -fsyntax-only -verify
+// REQUIRES: system-windows
+
+
+int null[] = {
+#embed "NUL" limit(1) //expected-error {{device files are not yet supported by '#embed' directive}}
+};
More information about the cfe-commits
mailing list