Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* New KVM PV features (Marcelo, Wanpeng)
* valgrind fixes (Andrey)
* Remove clock reset notifiers (David)
* KConfig and Makefile cleanups (Paolo)
* Replay and icount improvements (Pavel)
* x86 FP fixes (Peter M.)
* TCG locking assertions (Roman)
* x86 support for mmap-ed -kernel/-initrd (Stefano)
* Other cleanups (Wei Yang, Yan Zhao, Tony)
* LSI fix for infinite loop (Prasad)
* ARM migration fix (Catherine)
* AVX512_BF16 feature (Jing)

# gpg: Signature made Tue 20 Aug 2019 19:00:54 BST
# gpg:                using RSA key BFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full]
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>" [full]
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream: (33 commits)
  x86: Intel AVX512_BF16 feature enabling
  scsi: lsi: exit infinite loop while executing script (CVE-2019-12068)
  test-bitmap: test set 1 bit case for bitmap_set
  migration: do not rom_reset() during incoming migration
  HACKING: Document 'struct' keyword usage
  kvm: vmxcap: Enhance with latest features
  cpus-common: nuke finish_safe_work
  icount: remove unnecessary gen_io_end calls
  icount: clean up cpu_can_io at the entry to the block
  replay: rename step-related variables and functions
  replay: refine replay-time module
  replay: fix replay shutdown
  util/qemu-timer: refactor deadline calculation for external timers
  replay: document development rules
  replay: add missing fix for internal function
  timer: last, remove last bits of last
  replay: Remove host_clock_last
  timer: Remove reset notifiers
  mc146818rtc: Remove reset notifiers
  memory: fix race between TCG and accesses to dirty bitmap
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 42 insertions, 29 deletions

diff --git a/include/hw/elf_ops.h b/include/hw/elf_ops.h
index 690f9238c8..1496d7e753 100644
--- a/include/hw/elf_ops.h
+++ b/include/hw/elf_ops.h
@@ -323,8 +323,9 @@ static int glue(load_elf, SZ)(const char *name, int fd,
     struct elfhdr ehdr;
     struct elf_phdr *phdr = NULL, *ph;
     int size, i, total_size;
-    elf_word mem_size, file_size;
+    elf_word mem_size, file_size, data_offset;
     uint64_t addr, low = (uint64_t)-1, high = 0;
+    GMappedFile *mapped_file = NULL;
     uint8_t *data = NULL;
     char label[128];
     int ret = ELF_LOAD_FAILED;
@@ -409,20 +410,32 @@ static int glue(load_elf, SZ)(const char *name, int fd,
         }
     }
 
+    /*
+     * Since we want to be able to modify the mapped buffer, we set the
+     * 'writeble' parameter to 'true'. Modifications to the buffer are not
+     * written back to the file.
+     */
+    mapped_file = g_mapped_file_new_from_fd(fd, true, NULL);
+    if (!mapped_file) {
+        goto fail;
+    }
+
     total_size = 0;
     for(i = 0; i < ehdr.e_phnum; i++) {
         ph = &phdr[i];
         if (ph->p_type == PT_LOAD) {
             mem_size = ph->p_memsz; /* Size of the ROM */
             file_size = ph->p_filesz; /* Size of the allocated data */
-            data = g_malloc0(file_size);
-            if (ph->p_filesz > 0) {
-                if (lseek(fd, ph->p_offset, SEEK_SET) < 0) {
-                    goto fail;
-                }
-                if (read(fd, data, file_size) != file_size) {
+            data_offset = ph->p_offset; /* Offset where the data is located */
+
+            if (file_size > 0) {
+                if (g_mapped_file_get_length(mapped_file) <
+                    file_size + data_offset) {
                     goto fail;
                 }
+
+                data = (uint8_t *)g_mapped_file_get_contents(mapped_file);
+                data += data_offset;
             }
 
             /* The ELF spec is somewhat vague about the purpose of the
@@ -513,25 +526,25 @@ static int glue(load_elf, SZ)(const char *name, int fd,
                 *pentry = ehdr.e_entry - ph->p_vaddr + ph->p_paddr;
             }
 
-            if (mem_size == 0) {
-                /* Some ELF files really do have segments of zero size;
-                 * just ignore them rather than trying to create empty
-                 * ROM blobs, because the zero-length blob can falsely
-                 * trigger the overlapping-ROM-blobs check.
-                 */
-                g_free(data);
-            } else {
+            /* Some ELF files really do have segments of zero size;
+             * just ignore them rather than trying to create empty
+             * ROM blobs, because the zero-length blob can falsely
+             * trigger the overlapping-ROM-blobs check.
+             */
+            if (mem_size != 0) {
                 if (load_rom) {
                     snprintf(label, sizeof(label), "phdr #%d: %s", i, name);
 
-                    /* rom_add_elf_program() seize the ownership of 'data' */
-                    rom_add_elf_program(label, data, file_size, mem_size,
-                                        addr, as);
+                    /*
+                     * rom_add_elf_program() takes its own reference to
+                     * 'mapped_file'.
+                     */
+                    rom_add_elf_program(label, mapped_file, data, file_size,
+                                        mem_size, addr, as);
                 } else {
                     address_space_write(as ? as : &address_space_memory,
                                         addr, MEMTXATTRS_UNSPECIFIED,
                                         data, file_size);
-                    g_free(data);
                 }
             }
 
@@ -547,14 +560,16 @@ static int glue(load_elf, SZ)(const char *name, int fd,
             struct elf_note *nhdr = NULL;
 
             file_size = ph->p_filesz; /* Size of the range of ELF notes */
-            data = g_malloc0(file_size);
-            if (ph->p_filesz > 0) {
-                if (lseek(fd, ph->p_offset, SEEK_SET) < 0) {
-                    goto fail;
-                }
-                if (read(fd, data, file_size) != file_size) {
+            data_offset = ph->p_offset; /* Offset where the notes are located */
+
+            if (file_size > 0) {
+                if (g_mapped_file_get_length(mapped_file) <
+                    file_size + data_offset) {
                     goto fail;
                 }
+
+                data = (uint8_t *)g_mapped_file_get_contents(mapped_file);
+                data += data_offset;
             }
 
             /*
@@ -570,19 +585,17 @@ static int glue(load_elf, SZ)(const char *name, int fd,
                     sizeof(struct elf_note) == sizeof(struct elf64_note);
                 elf_note_fn((void *)nhdr, (void *)&ph->p_align, is64);
             }
-            g_free(data);
             data = NULL;
         }
     }
 
-    g_free(phdr);
     if (lowaddr)
         *lowaddr = (uint64_t)(elf_sword)low;
     if (highaddr)
         *highaddr = (uint64_t)(elf_sword)high;
-    return total_size;
+    ret = total_size;
  fail:
-    g_free(data);
+    g_mapped_file_unref(mapped_file);
     g_free(phdr);
     return ret;
 }