From f5bc7f052e1e48a2fd934203954542d7bbb0aee5 Mon Sep 17 00:00:00 2001
From: Johannes Stoelp <johannes.stoelp@gmail.com>
Date: Wed, 24 Nov 2021 00:35:23 +0100
Subject: inline lookup of symbol version until API defined for goblin

---
 Cargo.lock  | 21 +++++++++++----------
 Cargo.toml  |  4 +---
 src/main.rs | 30 ++++++++++++++++++++++++++----
 3 files changed, 38 insertions(+), 17 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index faacac6..2837cd3 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -10,8 +10,9 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "goblin"
-version = "0.4.2"
-source = "git+https://github.com/johannst/goblin?branch=elf-gnu-symbol-versioning-utils#4893886664718b7627a572578b69de65a9f88e24"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32401e89c6446dcd28185931a01b1093726d0356820ac744023e6850689bf926"
 dependencies = [
  "log",
  "plain",
@@ -20,9 +21,9 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.102"
+version = "0.2.108"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a2a5ac8f984bfcf3a823267e5fde638acc3325f6496633a5da6bb6eb2171e103"
+checksum = "8521a1b57e76b1ec69af7599e75e38e7b7fad6610f037db8c79b127201b5d119"
 
 [[package]]
 name = "log"
@@ -41,18 +42,18 @@ checksum = "b4596b6d070b27117e987119b4dac604f3c58cfb0b191112e24771b2faeac1a6"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.29"
+version = "1.0.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b9f5105d4fdaab20335ca9565e106a5d9b82b6219b5ba735731124ac6711d23d"
+checksum = "ba508cc11742c0dc5c1659771673afbab7a0efab23aa17e854cbab0837ed0b43"
 dependencies = [
  "unicode-xid",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.9"
+version = "1.0.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c3d0b9745dc2debf507c8422de05d7226cc1f0644216dfdfead988f9b1ab32a7"
+checksum = "38bc8cc6a5f2e3655e0899c1b848643b2562f853f114bfec7be120678e3ace05"
 dependencies = [
  "proc-macro2",
 ]
@@ -79,9 +80,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "1.0.76"
+version = "1.0.81"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c6f107db402c2c2055242dbf4d2af0e69197202e9faacbef9571bbe47f5a1b84"
+checksum = "f2afee18b8beb5a596ecb4a2dce128c719b4ba399d34126b9e4396e3f9860966"
 dependencies = [
  "proc-macro2",
  "quote",
diff --git a/Cargo.toml b/Cargo.toml
index a8975b2..f2cc248 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,8 +8,6 @@ edition = "2018"
 libc   = "0.2"
 
 [dependencies.goblin]
-#version = "0.4"
-git = "https://github.com/johannst/goblin"
-branch = "elf-gnu-symbol-versioning-utils"
+version = "0.4"
 default-features = false
 features = ["std", "elf32", "elf64", "endian_fd"]
diff --git a/src/main.rs b/src/main.rs
index 08cf086..ca0e47e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -88,8 +88,10 @@ unsafe fn get_vdso_sym(
         )
         .ok_or(Error::SymbolNotFound(symbol_name.0.into()))?;
 
-    let found_symbol_version = elf
+    // Get the corresponding ElfVersym entry.
+    let versym = elf
         .versym
+        .as_ref()
         .ok_or(Error::SymbolVersionError(
             "Missing ELF section Versym".into(),
         ))?
@@ -97,8 +99,24 @@ unsafe fn get_vdso_sym(
         .ok_or(Error::SymbolVersionError(format!(
             "No Versym entry for symbol with idx {} found",
             idx
-        )))?
-        .find_version(&elf.verdef, &elf.verneed, &elf.dynstrtab)
+        )))?;
+
+    // Get the defined symbol version for the ElfVersym entry from the ElfVerdef section.
+    let found_symbol_version = elf
+        .verdef
+        .as_ref()
+        .ok_or(Error::SymbolVersionError(
+            "Missing ELF section Verdef".into(),
+        ))?
+        .iter()
+        .find_map(|vd| {
+            if !versym.is_local() && !versym.is_global() && vd.vd_ndx == versym.version() {
+                let vda0 = vd.iter().next()?;
+                elf.dynstrtab.get_at(vda0.vda_name)
+            } else {
+                None
+            }
+        })
         .ok_or(Error::SymbolVersionError(format!(
             "No symbol version string found for symbol with idx {}",
             idx
@@ -136,7 +154,11 @@ fn main() -> Result<(), Error> {
         // SAFETY: orig_vdso describes a valid memory region as we got it from /proc/self/maps.
         let orig = get_vdso_sym(&orig_vdso, Sym("__vdso_gettimeofday"), Symver("LINUX_2.6"))?;
         // SAFETY: copy_vdso describes a valid and owned memory allocation.
-        let copy = get_vdso_sym(&copy_vdso.as_ref(), Sym("__vdso_gettimeofday"), Symver("LINUX_2.6"))?;
+        let copy = get_vdso_sym(
+            &copy_vdso.as_ref(),
+            Sym("__vdso_gettimeofday"),
+            Symver("LINUX_2.6"),
+        )?;
 
         (orig, copy)
     };
-- 
cgit v1.2.3