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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/rust/minidump-writer/src/linux/android.rs
parentInitial commit. (diff)
downloadfirefox-esr-upstream.tar.xz
firefox-esr-upstream.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/minidump-writer/src/linux/android.rs')
-rw-r--r--third_party/rust/minidump-writer/src/linux/android.rs146
1 files changed, 146 insertions, 0 deletions
diff --git a/third_party/rust/minidump-writer/src/linux/android.rs b/third_party/rust/minidump-writer/src/linux/android.rs
new file mode 100644
index 0000000000..0c8195cc0f
--- /dev/null
+++ b/third_party/rust/minidump-writer/src/linux/android.rs
@@ -0,0 +1,146 @@
+use crate::errors::AndroidError;
+use crate::maps_reader::MappingInfo;
+use crate::ptrace_dumper::PtraceDumper;
+use crate::thread_info::Pid;
+use goblin::elf;
+#[cfg(target_pointer_width = "32")]
+use goblin::elf::dynamic::dyn32::{Dyn, SIZEOF_DYN};
+#[cfg(target_pointer_width = "64")]
+use goblin::elf::dynamic::dyn64::{Dyn, SIZEOF_DYN};
+#[cfg(target_pointer_width = "32")]
+use goblin::elf::header::header32 as elf_header;
+#[cfg(target_pointer_width = "64")]
+use goblin::elf::header::header64 as elf_header;
+#[cfg(target_pointer_width = "32")]
+use goblin::elf::program_header::program_header32::ProgramHeader;
+#[cfg(target_pointer_width = "64")]
+use goblin::elf::program_header::program_header64::ProgramHeader;
+use std::ffi::c_void;
+
+type Result<T> = std::result::Result<T, AndroidError>;
+
+// From /usr/include/elf.h of the android SDK
+// #define DT_ANDROID_REL (DT_LOOS + 2)
+// #define DT_ANDROID_RELSZ (DT_LOOS + 3)
+// #define DT_ANDROID_RELA (DT_LOOS + 4)
+// #define DT_ANDROID_RELASZ (DT_LOOS + 5)
+#[cfg(target_pointer_width = "64")]
+const DT_ANDROID_REL: u64 = elf::dynamic::DT_LOOS + 2;
+#[cfg(target_pointer_width = "64")]
+const DT_ANDROID_RELA: u64 = elf::dynamic::DT_LOOS + 4;
+#[cfg(target_pointer_width = "32")]
+const DT_ANDROID_REL: u32 = (elf::dynamic::DT_LOOS + 2) as u32;
+#[cfg(target_pointer_width = "32")]
+const DT_ANDROID_RELA: u32 = (elf::dynamic::DT_LOOS + 4) as u32;
+
+struct DynVaddresses {
+ min_vaddr: usize,
+ dyn_vaddr: usize,
+ dyn_count: usize,
+}
+
+fn has_android_packed_relocations(pid: Pid, load_bias: usize, vaddrs: DynVaddresses) -> Result<()> {
+ let dyn_addr = load_bias + vaddrs.dyn_vaddr;
+ for idx in 0..vaddrs.dyn_count {
+ let addr = (dyn_addr + SIZEOF_DYN * idx) as *mut c_void;
+ let dyn_data = PtraceDumper::copy_from_process(pid, addr, SIZEOF_DYN)?;
+ // TODO: Couldn't find a nice way to use goblin for that, to avoid the unsafe-block
+ let dyn_obj: Dyn;
+ unsafe {
+ dyn_obj = std::mem::transmute::<[u8; SIZEOF_DYN], Dyn>(dyn_data.as_slice().try_into()?);
+ }
+
+ if dyn_obj.d_tag == DT_ANDROID_REL || dyn_obj.d_tag == DT_ANDROID_RELA {
+ return Ok(());
+ }
+ }
+ Err(AndroidError::NoRelFound)
+}
+
+fn get_effective_load_bias(pid: Pid, ehdr: &elf_header::Header, address: usize) -> usize {
+ let ph = parse_loaded_elf_program_headers(pid, ehdr, address);
+ // If |min_vaddr| is non-zero and we find Android packed relocation tags,
+ // return the effective load bias.
+
+ if ph.min_vaddr != 0 {
+ let load_bias = address - ph.min_vaddr;
+ if has_android_packed_relocations(pid, load_bias, ph).is_ok() {
+ return load_bias;
+ }
+ }
+ // Either |min_vaddr| is zero, or it is non-zero but we did not find the
+ // expected Android packed relocations tags.
+ address
+}
+
+fn parse_loaded_elf_program_headers(
+ pid: Pid,
+ ehdr: &elf_header::Header,
+ address: usize,
+) -> DynVaddresses {
+ let phdr_addr = address + ehdr.e_phoff as usize;
+ let mut min_vaddr = usize::MAX;
+ let mut dyn_vaddr = 0;
+ let mut dyn_count = 0;
+
+ let phdr_opt = PtraceDumper::copy_from_process(
+ pid,
+ phdr_addr as *mut c_void,
+ elf_header::SIZEOF_EHDR * ehdr.e_phnum as usize,
+ );
+ if let Ok(ph_data) = phdr_opt {
+ // TODO: The original C code doesn't have error-handling here at all.
+ // We silently ignore "not parsable" for now, but might bubble it up.
+ // TODO2: `from_bytes` might panic, `parse()` would return a Result<>, so maybe better
+ // to switch to that at some point.
+ for phdr in ProgramHeader::from_bytes(&ph_data, ehdr.e_phnum as usize) {
+ let p_vaddr = phdr.p_vaddr as usize;
+ if phdr.p_type == elf::program_header::PT_LOAD && p_vaddr < min_vaddr {
+ min_vaddr = p_vaddr;
+ }
+
+ if phdr.p_type == elf::program_header::PT_DYNAMIC {
+ dyn_vaddr = p_vaddr;
+ dyn_count = phdr.p_memsz as usize / SIZEOF_DYN;
+ }
+ }
+ }
+
+ DynVaddresses {
+ min_vaddr,
+ dyn_vaddr,
+ dyn_count,
+ }
+}
+
+pub fn late_process_mappings(pid: Pid, mappings: &mut [MappingInfo]) -> Result<()> {
+ // Only consider exec mappings that indicate a file path was mapped, and
+ // where the ELF header indicates a mapped shared library.
+ for mut map in mappings
+ .iter_mut()
+ .filter(|m| m.executable && m.name.as_ref().map_or(false, |n| n.starts_with("/")))
+ {
+ let ehdr_opt = PtraceDumper::copy_from_process(
+ pid,
+ map.start_address as *mut c_void,
+ elf_header::SIZEOF_EHDR,
+ )
+ .ok()
+ .and_then(|x| elf_header::Header::parse(&x).ok());
+
+ if let Some(ehdr) = ehdr_opt {
+ if ehdr.e_type == elf_header::ET_DYN {
+ // Compute the effective load bias for this mapped library, and update
+ // the mapping to hold that rather than |start_addr|, at the same time
+ // adjusting |size| to account for the change in |start_addr|. Where
+ // the library does not contain Android packed relocations,
+ // GetEffectiveLoadBias() returns |start_addr| and the mapping entry
+ // is not changed.
+ let load_bias = get_effective_load_bias(pid, &ehdr, map.start_address);
+ map.size += map.start_address - load_bias;
+ map.start_address = load_bias;
+ }
+ }
+ }
+ Ok(())
+}