mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-07-03 17:58:30 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Fix pledge() thread killing semantics

Browse source 
- tkill(tid, sig) should be allowed by stdio
- tgkill(getpid(), tid, sig) should be allowed by stdio

Fixes #628
This commit is contained in:
Justine Tunney 2022-09-19 15:31:16 -07:00
parent c7a8cd21e9
commit 1ea01fc905
No known key found for this signature in database
GPG key ID: BE714B4575D6E328
2 changed files with 45 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

20
libc/calls/pledge-linux.c
View file

@ -540,7 +540,8 @@ static const uint16_t kPledgeStdio[] = {
__NR_linux_sigsuspend, //
__NR_linux_sigpending, //
__NR_linux_kill | SELF, //
__NR_linux_tkill | SELF, //
__NR_linux_tkill, //
__NR_linux_tgkill | SELF, //
__NR_linux_socketpair, //
__NR_linux_getrusage, //
__NR_linux_times, //
@ -691,6 +692,7 @@ static const uint16_t kPledgeProc[] = {
__NR_linux_vfork, //
__NR_linux_clone | RESTRICT, //
__NR_linux_kill, //
__NR_linux_tgkill, //
__NR_linux_setsid, //
__NR_linux_setpgid, //
__NR_linux_prlimit, //
@ -707,8 +709,6 @@ static const uint16_t kPledgeProc[] = {
__NR_linux_sched_setaffinity, //
__NR_linux_sched_getparam, //
__NR_linux_sched_setparam, //
__NR_linux_tkill, //
__NR_linux_tgkill, //
};
static const uint16_t kPledgeId[] = {
@ -1028,15 +1028,15 @@ static privileged void AllowKillSelf(struct Filter *f) {
AppendFilter(f, PLEDGE(fragment));
}
// The first argument of tkill() must be
// The first argument of tgkill() must be
//
// - gettid()
// - getpid()
//
static privileged void AllowTkillSelf(struct Filter *f) {
static privileged void AllowTgkillSelf(struct Filter *f) {
struct sock_filter fragment[] = {
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, __NR_linux_tkill, 0, 4),
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, __NR_linux_tgkill, 0, 4),
BPF_STMT(BPF_LD | BPF_W | BPF_ABS, OFF(args[0])),
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, GetTid(), 0, 1),
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, GetPid(), 0, 1),
BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
BPF_STMT(BPF_LD | BPF_W | BPF_ABS, OFF(nr)),
};
@ -1949,8 +1949,8 @@ static privileged void AppendPledge(struct Filter *f, //
case __NR_linux_kill | SELF:
AllowKillSelf(f);
break;
case __NR_linux_tkill | SELF:
AllowTkillSelf(f);
case __NR_linux_tgkill | SELF:
AllowTgkillSelf(f);
break;
default:
notpossible;