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locate VDSO by calling libc::getauxval #20

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locate VDSO by calling libc::getauxval #20

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5 changes: 1 addition & 4 deletions Cargo.toml
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Original file line number Diff line number Diff line change
Expand Up @@ -23,9 +23,6 @@ maintenance = { status = "actively-developed" }
is-it-maintained-issue-resolution = { repository = "enarx/vdso" }
is-it-maintained-open-issues = { repository = "enarx/vdso" }

[dev-dependencies]
libc = "0.2.67"

[dependencies]
crt0stack = "0.1"
goblin = "0.6.0"
libc = "0.2.67"
14 changes: 6 additions & 8 deletions src/lib.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -5,7 +5,6 @@
#![deny(missing_docs)]
#![deny(clippy::all)]

use crt0stack::{Entry, Reader};
use std::ffi::CStr;
use std::os::raw::c_char;
use std::slice::from_raw_parts;
Expand Down Expand Up @@ -112,14 +111,13 @@ pub struct Vdso<'a>(&'a Header);
impl Vdso<'static> {
/// Locates the vDSO by parsing the auxiliary vectors
pub fn locate() -> Option<Self> {
for aux in Reader::from_environ().done() {
if let Entry::SysInfoEHdr(addr) = aux {
let hdr = unsafe { Header::from_ptr(&*(addr as *const _))? };
return Some(Self(hdr));
}
let val = unsafe { libc::getauxval(libc::AT_SYSINFO_EHDR) };
// getauxval returns 0 if entry was not found
if val == 0 {
return None;
}

None
let hdr = unsafe { Header::from_ptr(&*(val as *const _))? };
Some(Self(hdr))
}
}

Expand Down