BusyBox is unable to run properly on non-root applications due to seccomp introduced in Android 8.0.
The SDK-21 libc.a has system call wrappers that uses the system calls on the whitelist, so binaries compiled with the updated libc can work properly.
1. Introduce new applet: imgtool for better separation from the main program
2. Actually mount the image and check statvfs for free space in the image
This shall eliminate any possible module installation failure from image resizing issues.
The &cmd will return a pointer which point to a pointer of cmdline.
It is a memory address which is usually 8 bytes in 64 bits machine.
However, the struct cmdline is 4 bytes. This will cause setting zero
beyond the bound.
Below is a simple example to show the differentiation:
struct cmdline {
char skip_initramfs;
char slot[3];
};
static void parse_cmdline(struct cmdline *cmd)
{
printf("%lu\n", sizeof(*cmd)); /* 4 */
printf("%lu\n", sizeof(&cmd)); /* 8 */
}
int main()
{
struct cmdline cmd;
parse_cmdline(&cmd);
return 0;
}
This patch prevents this.
Signed-off-by: npes87184 <npes87184@gmail.com>
In previous implementations, proc_monitor checks whether the mount namespace of an app is actually separated from zygote using a list generated at startup.
However, for some unknown reason, some devices (e.g. Samsung) has multiple zygote servers running in the background.
This means that app processes spawned from the unlisted zygotes are not checked whether the separation is done or not, causing MagiskHide unmount stuffs in the namespace of zygote, and since zygote is the "mother" of all apps, all apps will no longer have root access.
Since I'm not sure of the reason why multiple zygotes exists, so instead of checking the namespace against a list, compare the current namespace against the parent process's namespace.
This will make sure the namespace is NOT the same as the parent process, which is supposed to be the zygote server.
It's not important to check the return value of unlink(2) or even verify
that the file exists. If this code is running, it means the system has
rebooted, and thus the update file, if any, should be removed so that
MagiskManager doesn't keep displaying the same message. We also handle
this before we handle "disable" so that disabled modules don't keep
requesting a reboot to update.
