2c89513395
The bpf_cgroup_from_id kfunc relies on cgroup_get_from_id to obtain the cgroup corresponding to a given cgroup ID. This helper can be called in a lot of contexts where the current thread can be random. A recent example was its use in sched_ext's ops.tick(), to obtain the root cgroup pointer. Since the current task can be whatever random user space task preempted by the timer tick, this makes the behavior of the helper unreliable. Refactor out __cgroup_get_from_id as the non-namespace aware version of cgroup_get_from_id, and change bpf_cgroup_from_id to make use of it. There is no compatibility breakage here, since changing the namespace against which the lookup is being done to the root cgroup namespace only permits a wider set of lookups to succeed now. The cgroup IDs across namespaces are globally unique, and thus don't need to be retranslated. Reported-by: Dan Schatzberg <dschatzberg@meta.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20250915032618.1551762-2-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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| .. | ||
| cgroup-internal.h | ||
| cgroup-v1.c | ||
| cgroup.c | ||
| cpuset-internal.h | ||
| cpuset-v1.c | ||
| cpuset.c | ||
| debug.c | ||
| dmem.c | ||
| freezer.c | ||
| legacy_freezer.c | ||
| Makefile | ||
| misc.c | ||
| namespace.c | ||
| pids.c | ||
| rdma.c | ||
| rstat.c | ||