summaryrefslogtreecommitdiffstats
path: root/kernel/events
diff options
context:
space:
mode:
authorSong Liu <song@kernel.org>2022-02-03 16:40:57 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-02-16 12:51:47 +0100
commit30d9f3cbe47e1018ddc8069ac5b5c9e66fbdf727 (patch)
tree58de3ce987df304dab6fb8771528cd50e30b3fd5 /kernel/events
parent48fe82f8a7fa7590740d74978c97e3549883a6f6 (diff)
downloadlinux-stable-30d9f3cbe47e1018ddc8069ac5b5c9e66fbdf727.tar.gz
linux-stable-30d9f3cbe47e1018ddc8069ac5b5c9e66fbdf727.tar.bz2
linux-stable-30d9f3cbe47e1018ddc8069ac5b5c9e66fbdf727.zip
perf: Fix list corruption in perf_cgroup_switch()
commit 5f4e5ce638e6a490b976ade4a40017b40abb2da0 upstream. There's list corruption on cgrp_cpuctx_list. This happens on the following path: perf_cgroup_switch: list_for_each_entry(cgrp_cpuctx_list) cpu_ctx_sched_in ctx_sched_in ctx_pinned_sched_in merge_sched_in perf_cgroup_event_disable: remove the event from the list Use list_for_each_entry_safe() to allow removing an entry during iteration. Fixes: 058fe1c0440e ("perf/core: Make cgroup switch visit only cpuctxs with cgroup events") Signed-off-by: Song Liu <song@kernel.org> Reviewed-by: Rik van Riel <riel@surriel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20220204004057.2961252-1-song@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/events')
-rw-r--r--kernel/events/core.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index e6e11b598438..2adde229d1af 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -798,7 +798,7 @@ static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list);
*/
static void perf_cgroup_switch(struct task_struct *task, int mode)
{
- struct perf_cpu_context *cpuctx;
+ struct perf_cpu_context *cpuctx, *tmp;
struct list_head *list;
unsigned long flags;
@@ -809,7 +809,7 @@ static void perf_cgroup_switch(struct task_struct *task, int mode)
local_irq_save(flags);
list = this_cpu_ptr(&cgrp_cpuctx_list);
- list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) {
+ list_for_each_entry_safe(cpuctx, tmp, list, cgrp_cpuctx_entry) {
WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0);
perf_ctx_lock(cpuctx, cpuctx->task_ctx);