Fix buffer overflow in connect.cpp

This commit is contained in:
topjohnwu 2022-02-06 05:51:35 -08:00
parent ff7ac582f0
commit a4f97fa151

View File

@ -9,12 +9,6 @@
using namespace std;
enum {
NAMED_ACTIVITY,
PKG_ACTIVITY,
CONTENT_PROVIDER
};
#define CALL_PROVIDER \
exe, "/system/bin", "com.android.commands.content.Content", \
"call", "--uri", target, "--user", user, "--method", action
@ -27,11 +21,13 @@ exe, "/system/bin", "com.android.commands.am.Am", \
// 0x18000020 = FLAG_ACTIVITY_NEW_TASK|FLAG_ACTIVITY_MULTIPLE_TASK|FLAG_INCLUDE_STOPPED_PACKAGES
#define get_user(info) \
(info->cfg[SU_MULTIUSER_MODE] == MULTIUSER_MODE_USER \
? info->uid / 100000 : 0)
((info)->cfg[SU_MULTIUSER_MODE] == MULTIUSER_MODE_USER \
? to_user_id((info)->uid) : 0)
#define get_cmd(to) \
(to.command.empty() ? (to.shell.empty() ? DEFAULT_SHELL : to.shell.data()) : to.command.data())
((to).command.empty() ? \
((to).shell.empty() ? DEFAULT_SHELL : (to).shell.data()) : \
(to).command.data())
class Extra {
const char *key;
@ -45,19 +41,21 @@ class Extra {
bool bool_val;
const char *str_val;
};
char buf[32];
string str;
public:
Extra(const char *k, int v): key(k), type(INT), int_val(v) {}
Extra(const char *k, bool v): key(k), type(BOOL), bool_val(v) {}
Extra(const char *k, const char *v): key(k), type(STRING), str_val(v) {}
void add_intent(vector<const char *> &vec) {
char buf[32];
const char *val;
switch (type) {
case INT:
vec.push_back("--ei");
sprintf(buf, "%d", int_val);
val = buf;
snprintf(buf, sizeof(buf), "%d", int_val);
str = buf;
val = str.data();
break;
case BOOL:
vec.push_back("--ez");
@ -73,19 +71,25 @@ public:
}
void add_bind(vector<const char *> &vec) {
char buf[32];
str = key;
switch (type) {
case INT:
sprintf(buf, "%s:i:%d", key, int_val);
str += ":i:";
snprintf(buf, sizeof(buf), "%d", int_val);
str += buf;
break;
case BOOL:
sprintf(buf, "%s:b:%s", key, bool_val ? "true" : "false");
str += ":b:";
str += bool_val ? "true" : "false";
break;
case STRING:
sprintf(buf, "%s:s:%s", key, str_val);
str += ":s:";
str += str_val;
break;
}
vec.push_back("--extra");
vec.push_back(buf);
vec.push_back(str.data());
}
};
@ -100,7 +104,7 @@ static bool check_no_error(int fd) {
}
static void exec_cmd(const char *action, vector<Extra> &data,
const shared_ptr<su_info> &info, int mode = CONTENT_PROVIDER) {
const shared_ptr<su_info> &info, bool provider = true) {
char exe[128];
char target[128];
char user[4];
@ -117,8 +121,8 @@ static void exec_cmd(const char *action, vector<Extra> &data,
}
// First try content provider call method
if (mode >= CONTENT_PROVIDER) {
sprintf(target, "content://%s.provider", info->mgr_pkg.data());
if (provider) {
snprintf(target, sizeof(target), "content://%s.provider", info->mgr_pkg.data());
vector<const char *> args{ CALL_PROVIDER };
for (auto &e : data) {
e.add_bind(args);
@ -147,17 +151,15 @@ static void exec_cmd(const char *action, vector<Extra> &data,
.argv = args.data()
};
if (mode >= PKG_ACTIVITY) {
// Then try start activity without component name
strcpy(target, info->mgr_pkg.data());
// Then try start activity without package name
strlcpy(target, info->mgr_pkg.data(), sizeof(target));
exec_command_sync(exec);
if (check_no_error(exec.fd))
return;
}
// Finally, fallback to start activity with component name
args[4] = "-n";
sprintf(target, "%s/.ui.surequest.SuRequestActivity", info->mgr_pkg.data());
snprintf(target, sizeof(target), "%s/.ui.surequest.SuRequestActivity", info->mgr_pkg.data());
exec.fd = -2;
exec.fork = fork_dont_care;
exec_command(exec);
@ -205,7 +207,7 @@ int app_request(const shared_ptr<su_info> &info) {
extras.reserve(2);
extras.emplace_back("fifo", fifo);
extras.emplace_back("uid", info->uid);
exec_cmd("request", extras, info, PKG_ACTIVITY);
exec_cmd("request", extras, info, false);
// Wait for data input for at most 70 seconds
int fd = xopen(fifo, O_RDONLY | O_CLOEXEC);