[binutils-gdb] Fix an assertion failure in the AArch64 assembler triggered by incorrect instruction syntax.

[Nick Clifton]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=96cbfd9f0488e9536bfc27550ebf90cb1ecac93b

commit 96cbfd9f0488e9536bfc27550ebf90cb1ecac93b
Author: Nick Clifton <nickc@redhat.com>
Date:   Thu Jun 17 16:19:20 2021 +0100

    Fix an assertion failure in the AArch64 assembler triggered by incorrect instruction syntax.
    
            PR 27904
            * config/tc-aarch64.c (ldst_lo12_determine_real_reloc_type):
            Generate a syntax error message if the reloc qualifier does not
            match the instruction's size.

Diff:
---
 gas/ChangeLog                       |  7 +++++++
 gas/config/tc-aarch64.c             | 15 ++++++++++++---
 gas/testsuite/gas/aarch64/pr27904.d |  2 ++
 gas/testsuite/gas/aarch64/pr27904.l |  2 ++
 gas/testsuite/gas/aarch64/pr27904.s |  1 +
 5 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 821cc810e07..a1997d2c028 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,10 @@
+2021-06-17  Nick Clifton  <nickc@redhat.com>
+
+	PR 27904
+	* config/tc-aarch64.c (ldst_lo12_determine_real_reloc_type):
+	Generate a syntax error message if the reloc qualifier does not
+	match the instruction's size.
+
 2021-06-17  Clément Chigot  <clement.chigot@atos.net>
 
 	* config/tc-ppc.c (md_begin): Create bss section with dummy
diff --git a/gas/config/tc-aarch64.c b/gas/config/tc-aarch64.c
index 69705521f00..9ff2d6803dd 100644
--- a/gas/config/tc-aarch64.c
+++ b/gas/config/tc-aarch64.c
@@ -5591,7 +5591,7 @@ get_logsz (unsigned int size)
 static inline bfd_reloc_code_real_type
 ldst_lo12_determine_real_reloc_type (void)
 {
-  unsigned logsz;
+  unsigned logsz, max_logsz;
   enum aarch64_opnd_qualifier opd0_qlf = inst.base.operands[0].qualifier;
   enum aarch64_opnd_qualifier opd1_qlf = inst.base.operands[1].qualifier;
 
@@ -5650,13 +5650,22 @@ ldst_lo12_determine_real_reloc_type (void)
   gas_assert (opd1_qlf != AARCH64_OPND_QLF_NIL);
 
   logsz = get_logsz (aarch64_get_qualifier_esize (opd1_qlf));
+
   if (inst.reloc.type == BFD_RELOC_AARCH64_TLSLD_LDST_DTPREL_LO12
       || inst.reloc.type == BFD_RELOC_AARCH64_TLSLD_LDST_DTPREL_LO12_NC
       || inst.reloc.type == BFD_RELOC_AARCH64_TLSLE_LDST_TPREL_LO12
       || inst.reloc.type == BFD_RELOC_AARCH64_TLSLE_LDST_TPREL_LO12_NC)
-    gas_assert (logsz <= 3);
+    max_logsz = 3;
   else
-    gas_assert (logsz <= 4);
+    max_logsz = 4;
+
+  if (logsz > max_logsz)
+    {
+      /* SEE PR 27904 for an example of this.  */
+      set_fatal_syntax_error
+	(_("relocation qualifier does not match instruction size"));
+      return BFD_RELOC_AARCH64_NONE;
+    }
 
   /* In reloc.c, these pseudo relocation types should be defined in similar
      order as above reloc_ldst_lo12 array. Because the array index calculation
diff --git a/gas/testsuite/gas/aarch64/pr27904.d b/gas/testsuite/gas/aarch64/pr27904.d
new file mode 100644
index 00000000000..927b72a19b7
--- /dev/null
+++ b/gas/testsuite/gas/aarch64/pr27904.d
@@ -0,0 +1,2 @@
+#name: PR 27904
+#error_output: pr27904.l
diff --git a/gas/testsuite/gas/aarch64/pr27904.l b/gas/testsuite/gas/aarch64/pr27904.l
new file mode 100644
index 00000000000..c8629c68b12
--- /dev/null
+++ b/gas/testsuite/gas/aarch64/pr27904.l
@@ -0,0 +1,2 @@
+[^:]*: Assembler messages:
+[^:]*:1: Error: relocation qualifier does not match instruction size at operand 3 -- `ldr q24,\[x23,:dtprel_lo12_nc:sym\]'
diff --git a/gas/testsuite/gas/aarch64/pr27904.s b/gas/testsuite/gas/aarch64/pr27904.s
new file mode 100644
index 00000000000..904fe9dade1
--- /dev/null
+++ b/gas/testsuite/gas/aarch64/pr27904.s
@@ -0,0 +1 @@
+ldr q24, [x23, :dtprel_lo12_nc:sym]