From 91e3fdcefcf8c55ff8b9486017b53c732205950a Mon Sep 17 00:00:00 2001 From: Brian Silverman Date: Tue, 18 Sep 2018 17:08:27 -0700 Subject: [PATCH] Don't crash on some forms of invalid ELF files With a few tweaks, it will fail to look up symbol names in these cases instead. --- src/symbolize.cc | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/symbolize.cc b/src/symbolize.cc index a950365f6..17b75edb1 100644 --- a/src/symbolize.cc +++ b/src/symbolize.cc @@ -209,6 +209,9 @@ GetSectionHeaderByType(const int fd, ElfW(Half) sh_num, const off_t sh_offset, (sizeof(buf) > num_bytes_left) ? num_bytes_left : sizeof(buf); const ssize_t len = ReadFromOffset(fd, buf, num_bytes_to_read, sh_offset + i * sizeof(buf[0])); + if (len == -1) { + return false; + } SAFE_ASSERT(len % sizeof(buf[0]) == 0); const ssize_t num_headers_in_buf = len / sizeof(buf[0]); SAFE_ASSERT(num_headers_in_buf <= sizeof(buf) / sizeof(buf[0])); @@ -299,6 +302,9 @@ FindSymbol(uint64_t pc, const int fd, char *out, int out_size, // Read at most NUM_SYMBOLS symbols at once to save read() calls. ElfW(Sym) buf[NUM_SYMBOLS]; const ssize_t len = ReadFromOffset(fd, &buf, sizeof(buf), offset); + if (len == -1) { + return false; + } SAFE_ASSERT(len % sizeof(buf[0]) == 0); const ssize_t num_symbols_in_buf = len / sizeof(buf[0]); SAFE_ASSERT(num_symbols_in_buf <= sizeof(buf)/sizeof(buf[0]));