libprocessgroup: UIDs in linux are unsigned
We missed two incorrect specifiers in the previous commit with this same
title.
We use the %d format specificier for uid_t, which maps to
__kernel_uid32_t, which is unsigned. [1] This is undefined behavior
which can lead to paths with negative UIDs when erroneously large
values are passed for uid:
E libprocessgroup: No such cgroup attribute: /sys/fs/cgroup/uid_-89846/cgroup.freeze
Fix it with %u.
[1] https://cs.android.com/search?q=typedef.*__kernel_uid32_t&ss=android%2Fplatform%2Fsuperproject%2Fmain
Change-Id: Ica04b03526bd2e156f026a2797fe9912b259cd9f
diff --git a/libprocessgroup/processgroup.cpp b/libprocessgroup/processgroup.cpp
index 06d386f..4506439 100644
--- a/libprocessgroup/processgroup.cpp
+++ b/libprocessgroup/processgroup.cpp
@@ -206,11 +206,11 @@
}
static std::string ConvertUidToPath(const char* cgroup, uid_t uid) {
- return StringPrintf("%s/uid_%d", cgroup, uid);
+ return StringPrintf("%s/uid_%u", cgroup, uid);
}
static std::string ConvertUidPidToPath(const char* cgroup, uid_t uid, int pid) {
- return StringPrintf("%s/uid_%d/pid_%d", cgroup, uid, pid);
+ return StringPrintf("%s/uid_%u/pid_%d", cgroup, uid, pid);
}
static int RemoveProcessGroup(const char* cgroup, uid_t uid, int pid, unsigned int retries) {