[ELF] Reject error-prone meta characters in input section description
The lexer is overly permissive. When parsing file patterns in an input
section description and there is a missing `)`, we would accept many
non-sensible tokens (e.g. `}`) as patterns, leading to confusion, e.g.
`*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.text*)) } PROVIDE_HIDDEN(__code_end = .)`
(#81804).
Ideally, the lexer should be stateful to report more errors like GNU ld
and get rid of hacks like `ScriptLexer::maybeSplitExpr`, but that would
require a large rewrite of the lexer. For now, just reject certain
non-wildcard meta characters to detect common mistakes.
Pull Request: https://github.com/llvm/llvm-project/pull/84130
GitOrigin-RevId: 551e20d190868fe47f8efbfd1dbf38191cc2c95d
diff --git a/ELF/ScriptParser.cpp b/ELF/ScriptParser.cpp
index f0ede1f..3bb1de9 100644
--- a/ELF/ScriptParser.cpp
+++ b/ELF/ScriptParser.cpp
@@ -717,9 +717,19 @@
StringMatcher SectionMatcher;
// Break if the next token is ), EXCLUDE_FILE, or SORT*.
- while (!errorCount() && peek() != ")" && peek() != "EXCLUDE_FILE" &&
- peekSortKind() == SortSectionPolicy::Default)
+ while (!errorCount() && peekSortKind() == SortSectionPolicy::Default) {
+ StringRef s = peek();
+ if (s == ")" || s == "EXCLUDE_FILE")
+ break;
+ // Detect common mistakes when certain non-wildcard meta characters are
+ // used without a closing ')'.
+ if (!s.empty() && strchr("(){}", s[0])) {
+ skip();
+ setError("section pattern is expected");
+ break;
+ }
SectionMatcher.addPattern(unquote(next()));
+ }
if (!SectionMatcher.empty())
ret.push_back({std::move(excludeFilePat), std::move(SectionMatcher)});
diff --git a/test/ELF/linkerscript/wildcards.s b/test/ELF/linkerscript/wildcards.s
index 1eea278..e9ae722 100644
--- a/test/ELF/linkerscript/wildcards.s
+++ b/test/ELF/linkerscript/wildcards.s
@@ -91,26 +91,42 @@
.text : { *([.]abc .ab[v-y] ) }
}
-## Test a few non-wildcard meta characters rejected by GNU ld.
+## Test a few non-wildcard characters rejected by GNU ld.
#--- lbrace.lds
-# RUN: ld.lld -T lbrace.lds a.o -o out
+# RUN: not ld.lld -T lbrace.lds a.o 2>&1 | FileCheck %s --check-prefix=ERR-LBRACE --match-full-lines --strict-whitespace
+# ERR-LBRACE:{{.*}}: section pattern is expected
+# ERR-LBRACE-NEXT:>>> .text : { *(.a* { ) }
+# ERR-LBRACE-NEXT:>>> ^
SECTIONS {
.text : { *(.a* { ) }
}
-#--- lparen.lds
-## ( is recognized as a section name pattern. Note, ( is rejected by GNU ld.
-# RUN: ld.lld -T lparen.lds a.o -o out
-# RUN: llvm-objdump --section-headers out | FileCheck --check-prefix=SEC-NO %s
+#--- lbrace2.lds
+# RUN: not ld.lld -T lbrace2.lds a.o 2>&1 | FileCheck %s --check-prefix=ERR-LBRACE2 --match-full-lines --strict-whitespace
+# ERR-LBRACE2:{{.*}}: section pattern is expected
+# ERR-LBRACE2-NEXT:>>> .text : { *(.a*{) }
+# ERR-LBRACE2-NEXT:>>> ^
SECTIONS {
- .text : { *(.a* ( ) }
+ .text : { *(.a*{) }
+}
+
+#--- lparen.lds
+# RUN: not ld.lld -T lparen.lds a.o 2>&1 | FileCheck %s --check-prefix=ERR-LPAREN --match-full-lines --strict-whitespace
+# ERR-LPAREN:{{.*}}: section pattern is expected
+# ERR-LPAREN-NEXT:>>> .text : { *(.a* ( ) }
+# ERR-LPAREN-NEXT:>>> ^
+SECTIONS {
+ .text : { *(.a* ( ) }
}
#--- rbrace.lds
-# RUN: ld.lld -T rbrace.lds a.o -o out
+# RUN: not ld.lld -T rbrace.lds a.o 2>&1 | FileCheck %s --check-prefix=ERR-RBRACE --match-full-lines --strict-whitespace
+# ERR-RBRACE:{{.*}}: section pattern is expected
+# ERR-RBRACE-NEXT:>>> .text : { *(.a* x = 3; } ) }
+# ERR-RBRACE-NEXT:>>> ^
SECTIONS {
- .text : { *(.a* } ) }
+ .text : { *(.a* x = 3; } ) }
}
#--- rparen.lds
