@@ -61,6 +61,10 @@ struct image_info {
abi_ulong interpreter_loadmap_addr;
abi_ulong interpreter_pt_dynamic_addr;
struct image_info *other_info;
+
+ /* For target-specific processing of NT_GNU_PROPERTY_TYPE_0. */
+ uint32_t note_flags;
+
#ifdef TARGET_MIPS
int fp_abi;
int interp_fp_abi;
@@ -1522,6 +1522,15 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs,
#include "elf.h"
+static bool arch_parse_elf_property(uint32_t pr_type, uint32_t pr_datasz,
+ const uint32_t *data,
+ struct image_info *info,
+ Error **errp)
+{
+ g_assert_not_reached();
+}
+#define ARCH_USE_GNU_PROPERTY 0
+
struct exec
{
unsigned int a_info; /* Use macros N_MAGIC, etc for access */
@@ -2373,6 +2382,150 @@ void probe_guest_base(const char *image_name, abi_ulong guest_loaddr,
"@ 0x%" PRIx64 "\n", (uint64_t)guest_base);
}
+enum {
+ /* The string "GNU\0" as a magic number. */
+ GNU0_MAGIC = const_le32('G' | 'N' << 8 | 'U' << 16),
+ NOTE_DATA_SZ = 1 * KiB,
+ NOTE_NAME_SZ = 4,
+ ELF_GNU_PROPERTY_ALIGN = ELF_CLASS == ELFCLASS32 ? 4 : 8,
+};
+
+/*
+ * Process a single gnu_property entry.
+ * Return false for error.
+ */
+static bool parse_elf_property(const uint32_t *data, int *off, int datasz,
+ struct image_info *info, bool have_prev_type,
+ uint32_t *prev_type, Error **errp)
+{
+ uint32_t pr_type, pr_datasz, step;
+
+ if (*off > datasz || !QEMU_IS_ALIGNED(*off, ELF_GNU_PROPERTY_ALIGN)) {
+ goto error_data;
+ }
+ datasz -= *off;
+ data += *off / sizeof(uint32_t);
+
+ if (datasz < 2 * sizeof(uint32_t)) {
+ goto error_data;
+ }
+ pr_type = data[0];
+ pr_datasz = data[1];
+ data += 2;
+ datasz -= 2 * sizeof(uint32_t);
+ step = ROUND_UP(pr_datasz, ELF_GNU_PROPERTY_ALIGN);
+ if (step > datasz) {
+ goto error_data;
+ }
+
+ /* Properties are supposed to be unique and sorted on pr_type. */
+ if (have_prev_type && pr_type <= *prev_type) {
+ if (pr_type == *prev_type) {
+ error_setg(errp, "Duplicate property in PT_GNU_PROPERTY");
+ } else {
+ error_setg(errp, "Unsorted property in PT_GNU_PROPERTY");
+ }
+ return false;
+ }
+ *prev_type = pr_type;
+
+ if (!arch_parse_elf_property(pr_type, pr_datasz, data, info, errp)) {
+ return false;
+ }
+
+ *off += 2 * sizeof(uint32_t) + step;
+ return true;
+
+ error_data:
+ error_setg(errp, "Ill-formed property in PT_GNU_PROPERTY");
+ return false;
+}
+
+/* Process NT_GNU_PROPERTY_TYPE_0. */
+static bool parse_elf_properties(int image_fd,
+ struct image_info *info,
+ const struct elf_phdr *phdr,
+ char bprm_buf[BPRM_BUF_SIZE],
+ Error **errp)
+{
+ union {
+ struct elf_note nhdr;
+ uint32_t data[NOTE_DATA_SZ / sizeof(uint32_t)];
+ } note;
+
+ int n, off, datasz;
+ bool have_prev_type;
+ uint32_t prev_type;
+
+ /* Unless the arch requires properties, ignore them. */
+ if (!ARCH_USE_GNU_PROPERTY) {
+ return true;
+ }
+
+ /* If the properties are crazy large, that's too bad. */
+ n = phdr->p_filesz;
+ if (n > sizeof(note)) {
+ error_setg(errp, "PT_GNU_PROPERTY too large");
+ return false;
+ }
+ if (n < sizeof(note.nhdr)) {
+ error_setg(errp, "PT_GNU_PROPERTY too small");
+ 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;
+ }
+ }
+
+ /*
+ * The contents of a valid PT_GNU_PROPERTY is a sequence
+ * of uint32_t -- swap them all now.
+ */
+#ifdef BSWAP_NEEDED
+ for (int i = 0; i < n / 4; i++) {
+ bswap32s(note.data + i);
+ }
+#endif
+
+ /*
+ * Note that nhdr is 3 words, and that the "name" described by namesz
+ * immediately follows nhdr and is thus at the 4th word. Further, all
+ * of the inputs to the kernel's round_up are multiples of 4.
+ */
+ if (note.nhdr.n_type != NT_GNU_PROPERTY_TYPE_0 ||
+ note.nhdr.n_namesz != NOTE_NAME_SZ ||
+ note.data[3] != GNU0_MAGIC) {
+ error_setg(errp, "Invalid note in PT_GNU_PROPERTY");
+ return false;
+ }
+ off = sizeof(note.nhdr) + NOTE_NAME_SZ;
+
+ datasz = note.nhdr.n_descsz + off;
+ if (datasz > n) {
+ error_setg(errp, "Invalid note size in PT_GNU_PROPERTY");
+ return false;
+ }
+
+ have_prev_type = false;
+ prev_type = 0;
+ while (1) {
+ if (off == datasz) {
+ return true; /* end, exit ok */
+ }
+ if (!parse_elf_property(note.data, &off, datasz, info,
+ have_prev_type, &prev_type, errp)) {
+ return false;
+ }
+ have_prev_type = true;
+ }
+}
+
/* Load an ELF image into the address space.
IMAGE_NAME is the filename of the image, to use in error messages.
@@ -2467,6 +2620,10 @@ static void load_elf_image(const char *image_name, int image_fd,
goto exit_errmsg;
}
*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)) {
+ goto exit_errmsg;
+ }
}
}
This is generic support, with the code disabled for all targets. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- v9: Only map the startup executable with BTI; anything else must be handled by the interpreter. v10: Split out preparatory patches (pmm). v11: Mirror(-ish) the kernel's code structure (pmm). --- linux-user/qemu.h | 4 ++ linux-user/elfload.c | 157 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 161 insertions(+)