[gdb-11-branch:,2/3] readelf: Support SHT_RELR/DT_RELR for -r

Message ID 20220109174504.1120244-3-hjl.tools@gmail.com
State New
Headers show
Series
  • [gdb-11-branch:,1/3] readelf: Support RELR in -S and -d and output
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Commit Message

Simon Marchi via Gdb-patches Jan. 9, 2022, 5:45 p.m.
From: Fangrui Song <maskray@google.com>


The -r output for SHT_RELR looks like:

Relocation section '.relr.dyn' at offset 0x530 contains 4 entries:
  7 offsets
00000000000028c0
00000000000028c8
0000000000003ad0
0000000000003ad8
0000000000003ae0
0000000000003ae8
0000000000003af0

For --use-dynamic, the header looks like

    'RELR' relocation section at offset 0x530 contains 32 bytes:

include/
    * elf/common.h (DT_ENCODING): Bump to 38.
    * elf/external.h (Elf32_External_Relr): New.
    (Elf64_External_Relr): New.

(cherry picked from commit a7fd11862703e45d2774981a4888bc127d473b06)
---
 include/elf/common.h   | 2 +-
 include/elf/external.h | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

-- 
2.34.1

Patch

diff --git a/include/elf/common.h b/include/elf/common.h
index 8c6a595fea4..dff90c4d9e1 100644
--- a/include/elf/common.h
+++ b/include/elf/common.h
@@ -1053,13 +1053,13 @@ 
 #define DT_FINI_ARRAYSZ 28
 #define DT_RUNPATH	29
 #define DT_FLAGS	30
-#define DT_ENCODING	32
 #define DT_PREINIT_ARRAY   32
 #define DT_PREINIT_ARRAYSZ 33
 #define DT_SYMTAB_SHNDX    34
 #define DT_RELRSZ	35
 #define DT_RELR		36
 #define DT_RELRENT	37
+#define DT_ENCODING	38
 
 /* Note, the Oct 4, 1999 draft of the ELF ABI changed the values
    for DT_LOOS and DT_HIOS.  Some implementations however, use
diff --git a/include/elf/external.h b/include/elf/external.h
index b24985687e6..815e39c2837 100644
--- a/include/elf/external.h
+++ b/include/elf/external.h
@@ -211,6 +211,10 @@  typedef struct {
   unsigned char	r_addend[4];	/* Constant addend used to compute value */
 } Elf32_External_Rela;
 
+typedef struct {
+  unsigned char r_data[4];	/* RELR entry */
+} Elf32_External_Relr;
+
 typedef struct {
   unsigned char r_offset[8];	/* Location at which to apply the action */
   unsigned char	r_info[8];	/* index and type of relocation */
@@ -222,6 +226,10 @@  typedef struct {
   unsigned char	r_addend[8];	/* Constant addend used to compute value */
 } Elf64_External_Rela;
 
+typedef struct {
+  unsigned char r_data[8];	/* RELR entry */
+} Elf64_External_Relr;
+
 /* dynamic section structure */
 
 typedef struct {