When: - caller of dbghelp is a 64bit process, - invoking SymInitialize on a 32bit live target running under WOW64
SymInitialize fails because: - check_live_target() erroneously reads the 64bit PEB of the target, while it actually wants the 32bit PEB. - as the ELF base header address isn't set (hidden in CloudFileFlags) in the 64bit PEB, hence causing the failure
So ensure that check_live_target() actually reads the 32bit PEB when handling a 32bit process.
Signed-off-by: Eric Pouech eric.pouech@gmail.com
--- dlls/dbghelp/dbghelp.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/dlls/dbghelp/dbghelp.c b/dlls/dbghelp/dbghelp.c index 00d7b61fbd8..9d99f0d646a 100644 --- a/dlls/dbghelp/dbghelp.c +++ b/dlls/dbghelp/dbghelp.c @@ -286,7 +286,7 @@ const WCHAR *process_getenv(const struct process *process, const WCHAR *name) * check_live_target * */ -static BOOL check_live_target(struct process* pcs) +static BOOL check_live_target(struct process* pcs, BOOL wow64, BOOL child_wow64) { PROCESS_BASIC_INFORMATION pbi; ULONG_PTR base = 0, env = 0; @@ -300,11 +300,17 @@ static BOOL check_live_target(struct process* pcs)
if (!pcs->is_64bit) { + const char* peb32_addr; DWORD env32; PEB32 peb32; + C_ASSERT(sizeof(void*) != 4 || FIELD_OFFSET(RTL_USER_PROCESS_PARAMETERS, Environment) == 0x48); - if (!ReadProcessMemory(pcs->handle, pbi.PebBaseAddress, &peb32, sizeof(peb32), NULL)) return FALSE; - if (!ReadProcessMemory(pcs->handle, (char *)pbi.PebBaseAddress + 0x460 /* CloudFileFlags */, &base, sizeof(base), NULL)) return FALSE; + peb32_addr = (const char*)pbi.PebBaseAddress; + if (!wow64 && child_wow64) + /* current process is 64bit, while child process is 32 bit, need to read 32bit PEB */ + peb32_addr += 0x1000; + if (!ReadProcessMemory(pcs->handle, peb32_addr, &peb32, sizeof(peb32), NULL)) return FALSE; + if (!ReadProcessMemory(pcs->handle, peb32_addr + 0x460 /* CloudFileFlags */, &base, sizeof(base), NULL)) return FALSE; if (read_process_memory(pcs, peb32.ProcessParameters + 0x48, &env32, sizeof(env32))) env = env32; } else @@ -454,7 +460,7 @@ BOOL WINAPI SymInitializeW(HANDLE hProcess, PCWSTR UserSearchPath, BOOL fInvadeP pcs->next = process_first; process_first = pcs;
- if (check_live_target(pcs)) + if (check_live_target(pcs, wow64, child_wow64)) { if (fInvadeProcess) EnumerateLoadedModulesW64(hProcess, process_invade_cb, hProcess);