[RS6000] Fix potiential buffer overflow

	* config/rs6000/rs6000.c (rs6000_indirect_call_template_1): Increase
	str[] size to 160, and comment.

From-SVN: r268520

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index efe3f5bfe6e4ae8719a8de3266f74ff79a18fb38..3c52283d93cf5e181d7280eb32b404268675ea18 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2019-02-04  Alan Modra  <amodra@gmail.com>
+
+       * config/rs6000/rs6000.c (rs6000_indirect_call_template_1): Increase
+       str[] size to 160, and comment.
+
 2019-02-04  Alan Modra  <amodra@gmail.com>
 
        * config/rs6000/rs6000.c (rs6000_indirect_call_template_1),

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 7d417b626e801bc7eac5bfdb0a1d4b3516645963..711278c742257ba9f7817e9fbee5c3da0366e2ca 100644 (file)
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -21609,10 +21609,47 @@ rs6000_indirect_call_template_1 (rtx *operands, unsigned int funop,
                                 bool sibcall)
 {
   /* -Wformat-overflow workaround, without which gcc thinks that %u
-      might produce 10 digits.  */
+     might produce 10 digits.  Note that -Wformat-overflow will not
+     currently warn here for str[], so do not rely on a warning to
+     ensure str[] is correctly sized.  */
   gcc_assert (funop <= MAX_RECOG_OPERANDS);
 
-  static char str[144];  /* 1 spare */
+  /* Currently, funop is either 0 or 1.  The maximum string is always
+     a !speculate 64-bit __tls_get_addr call.
+
+     ABI_AIX:
+     .  9      ld 2,%3\n\t
+     . 27      .reloc .,R_PPC64_TLSGD,%2\n\t
+     . 29      .reloc .,R_PPC64_PLTSEQ,%z1\n\t
+     .  9      crset 2\n\t
+     . 27      .reloc .,R_PPC64_TLSGD,%2\n\t
+     . 30      .reloc .,R_PPC64_PLTCALL,%z1\n\t
+     . 10      beq%T1l-\n\t
+     . 10      ld 2,%4(1)
+     .---
+     .151
+
+     ABI_ELFv2:
+     . 27      .reloc .,R_PPC64_TLSGD,%2\n\t
+     . 29      .reloc .,R_PPC64_PLTSEQ,%z1\n\t
+     .  9      crset 2\n\t
+     . 27      .reloc .,R_PPC64_TLSGD,%2\n\t
+     . 30      .reloc .,R_PPC64_PLTCALL,%z1\n\t
+     . 10      beq%T1l-\n\t
+     . 10      ld 2,%3(1)
+     .---
+     .142
+
+     ABI_V4:
+     . 27      .reloc .,R_PPC64_TLSGD,%2\n\t
+     . 35      .reloc .,R_PPC64_PLTSEQ,%z1+32768\n\t
+     .  9      crset 2\n\t
+     . 27      .reloc .,R_PPC64_TLSGD,%2\n\t
+     . 36      .reloc .,R_PPC64_PLTCALL,%z1+32768\n\t
+     .  8      beq%T1l-
+     .---
+     .141  */
+  static char str[160];  /* 8 spare */
   char *s = str;
   const char *ptrload = TARGET_64BIT ? "d" : "wz";