Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 03dca28d authored by Yabin Cui's avatar Yabin Cui
Browse files

Fix alignment when reading note segment. 

ELF said that padding is present, if necessary, to ensure 4-byte
alignment for the descriptor and next note entry, but such padding
is not included in namesz and descsz.

Change-Id: I7896783f3d9a787772d56c49905f52a493c9fba1
parent e83d8a69

debuggerd/elf_utils.cpp

+4 −2
Original line number Diff line number Diff line
@@ -29,6 +29,8 @@ 


#include "elf_utils.h"



#define NOTE_ALIGN(size)  ((size + 3) & ~3)



template <typename HdrType, typename PhdrType, typename NhdrType>

static bool get_build_id(

    Backtrace* backtrace, uintptr_t base_addr, uint8_t* e_ident, std::string* build_id) {
@@ -60,7 +62,7 @@ static bool get_build_id( 
        addr += sizeof(nhdr);

        if (nhdr.n_type == NT_GNU_BUILD_ID) {

          // Skip the name (which is the owner and should be "GNU").

          addr += nhdr.n_namesz;

          addr += NOTE_ALIGN(nhdr.n_namesz);

          uint8_t build_id_data[128];

          if (nhdr.n_namesz > sizeof(build_id_data)) {

            ALOGE("Possible corrupted note, name size value is too large: %u",
@@ -80,7 +82,7 @@ static bool get_build_id( 
        } else {

          // Move past the extra note data.

          hdr_size -= sizeof(nhdr);

          size_t skip_bytes = nhdr.n_namesz + nhdr.n_descsz;

          size_t skip_bytes = NOTE_ALIGN(nhdr.n_namesz) + NOTE_ALIGN(nhdr.n_descsz);

          addr += skip_bytes;

          if (hdr_size < skip_bytes) {

            break;