From c7f17e7bd744dceff5708346d7c28ea2a08b7c18 Mon Sep 17 00:00:00 2001
From: Richard Henderson <richard.henderson@linaro.org>
Date: Wed, 21 Oct 2020 10:37:45 -0700
Subject: [PATCH] linux-user/elfload: Use Error for load_elf_image
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This is a bit clearer than open-coding some of this
with a bare c string.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201021173749.111103-9-richard.henderson@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 linux-user/elfload.c | 37 ++++++++++++++++++++-----------------
 1 file changed, 20 insertions(+), 17 deletions(-)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 107a628a9e..56fbda93d0 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -12,6 +12,7 @@
 #include "qemu/guest-random.h"
 #include "qemu/units.h"
 #include "qemu/selfmap.h"
+#include "qapi/error.h"
 
 #ifdef _ARCH_PPC64
 #undef ARCH_DLINFO
@@ -2392,15 +2393,16 @@ static void load_elf_image(const char *image_name, int image_fd,
     struct elf_phdr *phdr;
     abi_ulong load_addr, load_bias, loaddr, hiaddr, error;
     int i, retval;
-    const char *errmsg;
+    Error *err = NULL;
 
     /* First of all, some simple consistency checks */
-    errmsg = "Invalid ELF image for this architecture";
     if (!elf_check_ident(ehdr)) {
+        error_setg(&err, "Invalid ELF image for this architecture");
         goto exit_errmsg;
     }
     bswap_ehdr(ehdr);
     if (!elf_check_ehdr(ehdr)) {
+        error_setg(&err, "Invalid ELF image for this architecture");
         goto exit_errmsg;
     }
 
@@ -2444,13 +2446,11 @@ static void load_elf_image(const char *image_name, int image_fd,
             g_autofree char *interp_name = NULL;
 
             if (*pinterp_name) {
-                errmsg = "Multiple PT_INTERP entries";
+                error_setg(&err, "Multiple PT_INTERP entries");
                 goto exit_errmsg;
             }
+
             interp_name = g_malloc(eppnt->p_filesz);
-            if (!interp_name) {
-                goto exit_perror;
-            }
 
             if (eppnt->p_offset + eppnt->p_filesz <= BPRM_BUF_SIZE) {
                 memcpy(interp_name, bprm_buf + eppnt->p_offset,
@@ -2459,11 +2459,11 @@ static void load_elf_image(const char *image_name, int image_fd,
                 retval = pread(image_fd, interp_name, eppnt->p_filesz,
                                eppnt->p_offset);
                 if (retval != eppnt->p_filesz) {
-                    goto exit_perror;
+                    goto exit_read;
                 }
             }
             if (interp_name[eppnt->p_filesz - 1] != 0) {
-                errmsg = "Invalid PT_INTERP entry";
+                error_setg(&err, "Invalid PT_INTERP entry");
                 goto exit_errmsg;
             }
             *pinterp_name = g_steal_pointer(&interp_name);
@@ -2520,7 +2520,7 @@ static void load_elf_image(const char *image_name, int image_fd,
                             (ehdr->e_type == ET_EXEC ? MAP_FIXED : 0),
                             -1, 0);
     if (load_addr == -1) {
-        goto exit_perror;
+        goto exit_mmap;
     }
     load_bias = load_addr - loaddr;
 
@@ -2587,7 +2587,7 @@ static void load_elf_image(const char *image_name, int image_fd,
                                     image_fd, eppnt->p_offset - vaddr_po);
 
                 if (error == -1) {
-                    goto exit_perror;
+                    goto exit_mmap;
                 }
             }
 
@@ -2623,7 +2623,7 @@ static void load_elf_image(const char *image_name, int image_fd,
         } else if (eppnt->p_type == PT_MIPS_ABIFLAGS) {
             Mips_elf_abiflags_v0 abiflags;
             if (eppnt->p_filesz < sizeof(Mips_elf_abiflags_v0)) {
-                errmsg = "Invalid PT_MIPS_ABIFLAGS entry";
+                error_setg(&err, "Invalid PT_MIPS_ABIFLAGS entry");
                 goto exit_errmsg;
             }
             if (eppnt->p_offset + eppnt->p_filesz <= BPRM_BUF_SIZE) {
@@ -2633,7 +2633,7 @@ static void load_elf_image(const char *image_name, int image_fd,
                 retval = pread(image_fd, &abiflags, sizeof(Mips_elf_abiflags_v0),
                                eppnt->p_offset);
                 if (retval != sizeof(Mips_elf_abiflags_v0)) {
-                    goto exit_perror;
+                    goto exit_read;
                 }
             }
             bswap_mips_abiflags(&abiflags);
@@ -2658,13 +2658,16 @@ static void load_elf_image(const char *image_name, int image_fd,
 
  exit_read:
     if (retval >= 0) {
-        errmsg = "Incomplete read of file header";
-        goto exit_errmsg;
+        error_setg(&err, "Incomplete read of file header");
+    } else {
+        error_setg_errno(&err, errno, "Error reading file header");
     }
- exit_perror:
-    errmsg = strerror(errno);
+    goto exit_errmsg;
+ exit_mmap:
+    error_setg_errno(&err, errno, "Error mapping file");
+    goto exit_errmsg;
  exit_errmsg:
-    fprintf(stderr, "%s: %s\n", image_name, errmsg);
+    error_reportf_err(err, "%s: ", image_name);
     exit(-1);
 }