#undef ELF_ARCH
#endif
+#ifndef TARGET_ARCH_HAS_SIGTRAMP_PAGE
+#define TARGET_ARCH_HAS_SIGTRAMP_PAGE 0
+#endif
+
+typedef struct {
+ const uint8_t *image;
+ const uint32_t *relocs;
+ unsigned image_size;
+ unsigned reloc_count;
+ unsigned sigreturn_ofs;
+ unsigned rt_sigreturn_ofs;
+} VdsoImageInfo;
+
#define ELF_OSABI ELFOSABI_SYSV
/* from personality.h */
(*regs)[15] = tswapreg(env->regs[R_ESP]);
(*regs)[16] = tswapreg(env->segs[R_SS].selector & 0xffff);
}
-#endif
+
+/*
+ * i386 is the only target which supplies AT_SYSINFO for the vdso.
+ * All others only supply AT_SYSINFO_EHDR.
+ */
+#define DLINFO_ARCH_ITEMS (vdso_info != NULL)
+#define ARCH_DLINFO \
+ do { \
+ if (vdso_info) { \
+ NEW_AUX_ENT(AT_SYSINFO, vdso_info->entry); \
+ } \
+ } while (0)
+
+#endif /* TARGET_X86_64 */
+
+#define VDSO_HEADER "vdso.c.inc"
#define USE_ELF_CORE_DUMP
#define ELF_EXEC_PAGESIZE 4096
-#endif
+#endif /* TARGET_I386 */
#ifdef TARGET_ARM
#undef GET_FEATURE_ID
+#if TARGET_BIG_ENDIAN
+# define VDSO_HEADER "vdso-be.c.inc"
+#else
+# define VDSO_HEADER "vdso-le.c.inc"
+#endif
+
#endif /* not TARGET_AARCH64 */
#endif /* TARGET_ARM */
#ifdef USE_ELF_CORE_DUMP
static int elf_core_dump(int, const CPUArchState *);
#endif /* USE_ELF_CORE_DUMP */
-static void load_symbols(struct elfhdr *hdr, int fd, abi_ulong load_bias);
+static void load_symbols(struct elfhdr *hdr, const ImageSource *src,
+ abi_ulong load_bias);
/* Verify the portions of EHDR within E_IDENT for the target.
This can be performed before bswapping the entire header. */
static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
struct elfhdr *exec,
struct image_info *info,
- struct image_info *interp_info)
+ struct image_info *interp_info,
+ struct image_info *vdso_info)
{
abi_ulong sp;
abi_ulong u_argc, u_argv, u_envp, u_auxv;
}
size = (DLINFO_ITEMS + 1) * 2;
- if (k_base_platform)
+ if (k_base_platform) {
size += 2;
- if (k_platform)
+ }
+ if (k_platform) {
size += 2;
+ }
+ if (vdso_info) {
+ size += 2;
+ }
#ifdef DLINFO_ARCH_ITEMS
size += DLINFO_ARCH_ITEMS * 2;
#endif
if (u_platform) {
NEW_AUX_ENT(AT_PLATFORM, u_platform);
}
+ if (vdso_info) {
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, vdso_info->load_addr);
+ }
NEW_AUX_ENT (AT_NULL, 0);
#undef NEW_AUX_ENT
}
/* Process NT_GNU_PROPERTY_TYPE_0. */
-static bool parse_elf_properties(int image_fd,
+static bool parse_elf_properties(const ImageSource *src,
struct image_info *info,
const struct elf_phdr *phdr,
- char bprm_buf[BPRM_BUF_SIZE],
Error **errp)
{
union {
return false;
}
- if (phdr->p_offset + n <= BPRM_BUF_SIZE) {
- memcpy(¬e, bprm_buf + phdr->p_offset, n);
- } else {
- ssize_t len = pread(image_fd, ¬e, n, phdr->p_offset);
- if (len != n) {
- error_setg_errno(errp, errno, "Error reading file header");
- return false;
- }
+ if (!imgsrc_read(¬e, phdr->p_offset, n, src, errp)) {
+ return false;
}
/*
}
}
-/* Load an ELF image into the address space.
-
- IMAGE_NAME is the filename of the image, to use in error messages.
- IMAGE_FD is the open file descriptor for the image.
-
- BPRM_BUF is a copy of the beginning of the file; this of course
- contains the elf file header at offset 0. It is assumed that this
- buffer is sufficiently aligned to present no problems to the host
- in accessing data at aligned offsets within the buffer.
-
- On return: INFO values will be filled in, as necessary or available. */
+/**
+ * load_elf_image: Load an ELF image into the address space.
+ * @image_name: the filename of the image, to use in error messages.
+ * @src: the ImageSource from which to read.
+ * @info: info collected from the loaded image.
+ * @ehdr: the ELF header, not yet bswapped.
+ * @pinterp_name: record any PT_INTERP string found.
+ *
+ * On return: @info values will be filled in, as necessary or available.
+ */
-static void load_elf_image(const char *image_name, int image_fd,
- struct image_info *info, char **pinterp_name,
- char bprm_buf[BPRM_BUF_SIZE])
+static void load_elf_image(const char *image_name, const ImageSource *src,
+ struct image_info *info, struct elfhdr *ehdr,
+ char **pinterp_name)
{
- struct elfhdr *ehdr = (struct elfhdr *)bprm_buf;
- struct elf_phdr *phdr;
+ g_autofree struct elf_phdr *phdr = NULL;
abi_ulong load_addr, load_bias, loaddr, hiaddr, error;
- int i, retval, prot_exec;
+ int i, prot_exec;
Error *err = NULL;
- /* First of all, some simple consistency checks */
+ /*
+ * First of all, some simple consistency checks.
+ * Note that we rely on the bswapped ehdr staying in bprm_buf,
+ * for later use by load_elf_binary and create_elf_tables.
+ */
+ if (!imgsrc_read(ehdr, 0, sizeof(*ehdr), src, &err)) {
+ goto exit_errmsg;
+ }
if (!elf_check_ident(ehdr)) {
error_setg(&err, "Invalid ELF image for this architecture");
goto exit_errmsg;
goto exit_errmsg;
}
- i = ehdr->e_phnum * sizeof(struct elf_phdr);
- if (ehdr->e_phoff + i <= BPRM_BUF_SIZE) {
- phdr = (struct elf_phdr *)(bprm_buf + ehdr->e_phoff);
- } else {
- phdr = (struct elf_phdr *) alloca(i);
- retval = pread(image_fd, phdr, i, ehdr->e_phoff);
- if (retval != i) {
- goto exit_read;
- }
+ phdr = imgsrc_read_alloc(ehdr->e_phoff,
+ ehdr->e_phnum * sizeof(struct elf_phdr),
+ src, &err);
+ if (phdr == NULL) {
+ goto exit_errmsg;
}
bswap_phdr(phdr, ehdr->e_phnum);
goto exit_errmsg;
}
- interp_name = g_malloc(eppnt->p_filesz);
-
- if (eppnt->p_offset + eppnt->p_filesz <= BPRM_BUF_SIZE) {
- memcpy(interp_name, bprm_buf + eppnt->p_offset,
- eppnt->p_filesz);
- } else {
- retval = pread(image_fd, interp_name, eppnt->p_filesz,
- eppnt->p_offset);
- if (retval != eppnt->p_filesz) {
- goto exit_read;
- }
+ interp_name = imgsrc_read_alloc(eppnt->p_offset, eppnt->p_filesz,
+ src, &err);
+ if (interp_name == NULL) {
+ goto exit_errmsg;
}
if (interp_name[eppnt->p_filesz - 1] != 0) {
error_setg(&err, "Invalid PT_INTERP entry");
}
*pinterp_name = g_steal_pointer(&interp_name);
} else if (eppnt->p_type == PT_GNU_PROPERTY) {
- if (!parse_elf_properties(image_fd, info, eppnt, bprm_buf, &err)) {
+ if (!parse_elf_properties(src, info, eppnt, &err)) {
goto exit_errmsg;
}
} else if (eppnt->p_type == PT_GNU_STACK) {
* but no backing file segment.
*/
if (eppnt->p_filesz != 0) {
- error = target_mmap(vaddr_ps, eppnt->p_filesz + vaddr_po,
+ error = imgsrc_mmap(vaddr_ps, eppnt->p_filesz + vaddr_po,
elf_prot, MAP_PRIVATE | MAP_FIXED,
- image_fd, eppnt->p_offset - vaddr_po);
+ src, eppnt->p_offset - vaddr_po);
if (error == -1) {
goto exit_mmap;
}
#ifdef TARGET_MIPS
} else if (eppnt->p_type == PT_MIPS_ABIFLAGS) {
Mips_elf_abiflags_v0 abiflags;
- if (eppnt->p_filesz < sizeof(Mips_elf_abiflags_v0)) {
- error_setg(&err, "Invalid PT_MIPS_ABIFLAGS entry");
+
+ if (!imgsrc_read(&abiflags, eppnt->p_offset, sizeof(abiflags),
+ src, &err)) {
goto exit_errmsg;
}
- if (eppnt->p_offset + eppnt->p_filesz <= BPRM_BUF_SIZE) {
- memcpy(&abiflags, bprm_buf + eppnt->p_offset,
- sizeof(Mips_elf_abiflags_v0));
- } else {
- retval = pread(image_fd, &abiflags, sizeof(Mips_elf_abiflags_v0),
- eppnt->p_offset);
- if (retval != sizeof(Mips_elf_abiflags_v0)) {
- goto exit_read;
- }
- }
bswap_mips_abiflags(&abiflags);
info->fp_abi = abiflags.fp_abi;
#endif
}
if (qemu_log_enabled()) {
- load_symbols(ehdr, image_fd, load_bias);
+ load_symbols(ehdr, src, load_bias);
}
- debuginfo_report_elf(image_name, image_fd, load_bias);
+ debuginfo_report_elf(image_name, src->fd, load_bias);
mmap_unlock();
- close(image_fd);
+ close(src->fd);
return;
- exit_read:
- if (retval >= 0) {
- error_setg(&err, "Incomplete read of file header");
- } else {
- error_setg_errno(&err, errno, "Error reading file header");
- }
- goto exit_errmsg;
exit_mmap:
error_setg_errno(&err, errno, "Error mapping file");
goto exit_errmsg;
static void load_elf_interp(const char *filename, struct image_info *info,
char bprm_buf[BPRM_BUF_SIZE])
{
+ struct elfhdr ehdr;
+ ImageSource src;
int fd, retval;
Error *err = NULL;
exit(-1);
}
- if (retval < BPRM_BUF_SIZE) {
- memset(bprm_buf + retval, 0, BPRM_BUF_SIZE - retval);
+ src.fd = fd;
+ src.cache = bprm_buf;
+ src.cache_size = retval;
+
+ load_elf_image(filename, &src, info, &ehdr, NULL);
+}
+
+#ifdef VDSO_HEADER
+#include VDSO_HEADER
+#define vdso_image_info() &vdso_image_info
+#else
+#define vdso_image_info() NULL
+#endif
+
+static void load_elf_vdso(struct image_info *info, const VdsoImageInfo *vdso)
+{
+ ImageSource src;
+ struct elfhdr ehdr;
+ abi_ulong load_bias, load_addr;
+
+ src.fd = -1;
+ src.cache = vdso->image;
+ src.cache_size = vdso->image_size;
+
+ load_elf_image("<internal-vdso>", &src, info, &ehdr, NULL);
+ load_addr = info->load_addr;
+ load_bias = info->load_bias;
+
+ /*
+ * We need to relocate the VDSO image. The one built into the kernel
+ * is built for a fixed address. The one built for QEMU is not, since
+ * that requires close control of the guest address space.
+ * We pre-processed the image to locate all of the addresses that need
+ * to be updated.
+ */
+ for (unsigned i = 0, n = vdso->reloc_count; i < n; i++) {
+ abi_ulong *addr = g2h_untagged(load_addr + vdso->relocs[i]);
+ *addr = tswapal(tswapal(*addr) + load_bias);
}
- load_elf_image(filename, fd, info, NULL, bprm_buf);
+ /* Install signal trampolines, if present. */
+ if (vdso->sigreturn_ofs) {
+ default_sigreturn = load_addr + vdso->sigreturn_ofs;
+ }
+ if (vdso->rt_sigreturn_ofs) {
+ default_rt_sigreturn = load_addr + vdso->rt_sigreturn_ofs;
+ }
+
+ /* Remove write from VDSO segment. */
+ target_mprotect(info->start_data, info->end_data - info->start_data,
+ PROT_READ | PROT_EXEC);
}
static int symfind(const void *s0, const void *s1)
}
/* Best attempt to load symbols from this ELF object. */
-static void load_symbols(struct elfhdr *hdr, int fd, abi_ulong load_bias)
+static void load_symbols(struct elfhdr *hdr, const ImageSource *src,
+ abi_ulong load_bias)
{
int i, shnum, nsyms, sym_idx = 0, str_idx = 0;
- uint64_t segsz;
- struct elf_shdr *shdr;
+ g_autofree struct elf_shdr *shdr = NULL;
char *strings = NULL;
- struct syminfo *s = NULL;
- struct elf_sym *new_syms, *syms = NULL;
+ struct elf_sym *syms = NULL;
+ struct elf_sym *new_syms;
+ uint64_t segsz;
shnum = hdr->e_shnum;
- i = shnum * sizeof(struct elf_shdr);
- shdr = (struct elf_shdr *)alloca(i);
- if (pread(fd, shdr, i, hdr->e_shoff) != i) {
+ shdr = imgsrc_read_alloc(hdr->e_shoff, shnum * sizeof(struct elf_shdr),
+ src, NULL);
+ if (shdr == NULL) {
return;
}
found:
/* Now know where the strtab and symtab are. Snarf them. */
- s = g_try_new(struct syminfo, 1);
- if (!s) {
- goto give_up;
- }
segsz = shdr[str_idx].sh_size;
- s->disas_strtab = strings = g_try_malloc(segsz);
- if (!strings ||
- pread(fd, strings, segsz, shdr[str_idx].sh_offset) != segsz) {
+ strings = g_try_malloc(segsz);
+ if (!strings) {
goto give_up;
}
-
- segsz = shdr[sym_idx].sh_size;
- syms = g_try_malloc(segsz);
- if (!syms || pread(fd, syms, segsz, shdr[sym_idx].sh_offset) != segsz) {
+ if (!imgsrc_read(strings, shdr[str_idx].sh_offset, segsz, src, NULL)) {
goto give_up;
}
+ segsz = shdr[sym_idx].sh_size;
if (segsz / sizeof(struct elf_sym) > INT_MAX) {
- /* Implausibly large symbol table: give up rather than ploughing
- * on with the number of symbols calculation overflowing
+ /*
+ * Implausibly large symbol table: give up rather than ploughing
+ * on with the number of symbols calculation overflowing.
*/
goto give_up;
}
nsyms = segsz / sizeof(struct elf_sym);
+ syms = g_try_malloc(segsz);
+ if (!syms) {
+ goto give_up;
+ }
+ if (!imgsrc_read(syms, shdr[sym_idx].sh_offset, segsz, src, NULL)) {
+ goto give_up;
+ }
+
for (i = 0; i < nsyms; ) {
bswap_sym(syms + i);
/* Throw away entries which we do not need. */
goto give_up;
}
- /* Attempt to free the storage associated with the local symbols
- that we threw away. Whether or not this has any effect on the
- memory allocation depends on the malloc implementation and how
- many symbols we managed to discard. */
+ /*
+ * Attempt to free the storage associated with the local symbols
+ * that we threw away. Whether or not this has any effect on the
+ * memory allocation depends on the malloc implementation and how
+ * many symbols we managed to discard.
+ */
new_syms = g_try_renew(struct elf_sym, syms, nsyms);
if (new_syms == NULL) {
goto give_up;
qsort(syms, nsyms, sizeof(*syms), symcmp);
- s->disas_num_syms = nsyms;
+ {
+ struct syminfo *s = g_new(struct syminfo, 1);
+
+ s->disas_strtab = strings;
+ s->disas_num_syms = nsyms;
#if ELF_CLASS == ELFCLASS32
- s->disas_symtab.elf32 = syms;
+ s->disas_symtab.elf32 = syms;
#else
- s->disas_symtab.elf64 = syms;
+ s->disas_symtab.elf64 = syms;
#endif
- s->lookup_symbol = lookup_symbolxx;
- s->next = syminfos;
- syminfos = s;
-
+ s->lookup_symbol = lookup_symbolxx;
+ s->next = syminfos;
+ syminfos = s;
+ }
return;
-give_up:
- g_free(s);
+ give_up:
g_free(strings);
g_free(syms);
}
int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
{
- struct image_info interp_info;
- struct elfhdr elf_ex;
+ /*
+ * We need a copy of the elf header for passing to create_elf_tables.
+ * We will have overwritten the original when we re-use bprm->buf
+ * while loading the interpreter. Allocate the storage for this now
+ * and let elf_load_image do any swapping that may be required.
+ */
+ struct elfhdr ehdr;
+ struct image_info interp_info, vdso_info;
char *elf_interpreter = NULL;
char *scratch;
interp_info.fp_abi = MIPS_ABI_FP_UNKNOWN;
#endif
- load_elf_image(bprm->filename, bprm->fd, info,
- &elf_interpreter, bprm->buf);
-
- /* ??? We need a copy of the elf header for passing to create_elf_tables.
- If we do nothing, we'll have overwritten this when we re-use bprm->buf
- when we load the interpreter. */
- elf_ex = *(struct elfhdr *)bprm->buf;
+ load_elf_image(bprm->filename, &bprm->src, info, &ehdr, &elf_interpreter);
/* Do this so that we can load the interpreter, if need be. We will
change some of these later */
}
/*
- * TODO: load a vdso, which would also contain the signal trampolines.
- * Otherwise, allocate a private page to hold them.
+ * Load a vdso if available, which will amongst other things contain the
+ * signal trampolines. Otherwise, allocate a separate page for them.
*/
- if (TARGET_ARCH_HAS_SIGTRAMP_PAGE) {
+ const VdsoImageInfo *vdso = vdso_image_info();
+ if (vdso) {
+ load_elf_vdso(&vdso_info, vdso);
+ } else if (TARGET_ARCH_HAS_SIGTRAMP_PAGE) {
abi_long tramp_page = target_mmap(0, TARGET_PAGE_SIZE,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANON, -1, 0);
target_mprotect(tramp_page, TARGET_PAGE_SIZE, PROT_READ | PROT_EXEC);
}
- bprm->p = create_elf_tables(bprm->p, bprm->argc, bprm->envc, &elf_ex,
- info, (elf_interpreter ? &interp_info : NULL));
+ bprm->p = create_elf_tables(bprm->p, bprm->argc, bprm->envc, &ehdr, info,
+ elf_interpreter ? &interp_info : NULL,
+ vdso ? &vdso_info : NULL);
info->start_stack = bprm->p;
/* If we have an interpreter, set that as the program's entry point.
projects / mirror_qemu.git / blobdiff