As there are still possible cases when we expect code to work without
statistic inited, it's theoretically possible some day we again get an
update request for non-inited stat struct, and corrupt stack-protector
cookie and who knows what alse.

So add a sanity check to prevent it.

https://jira.sw.ru/browse/PSBM-96128

Signed-off-by: Konstantin Khorenko <[email protected]>
---
 fs/fuse/kio/pcs/fuse_stat.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/fs/fuse/kio/pcs/fuse_stat.c b/fs/fuse/kio/pcs/fuse_stat.c
index b57be607f5e1..c91bfe8b3bf7 100644
--- a/fs/fuse/kio/pcs/fuse_stat.c
+++ b/fs/fuse/kio/pcs/fuse_stat.c
@@ -31,6 +31,12 @@ static u64 lat_oreder_list[] = {
 
 static inline void fuse_val_stat_update(struct fuse_val_stat *s, u64 val)
 {
+       /*
+        * Sanity check. In case s == NULL, stack protector cookie is
+        * corrupted, quite difficult to debug.
+        */
+       BUG_ON(!s);
+
        preempt_disable();
        if (!__this_cpu_read(s->events)) {
                __this_cpu_write(s->val_min, val);
@@ -48,6 +54,11 @@ void fuse_latency_update(struct fuse_lat_stat *s, u64 val)
 {
        int i;
 
+       /*
+        * Sanity check. In case s == NULL, stack protector cookie is
+        * corrupted, quite difficult to debug.
+        */
+       BUG_ON(!s);
        this_cpu_inc(s->count);
        for (i = LAT_ORDER1; i <= LAT_ORDER5; i++) {
                if (likely(val <= lat_oreder_list[i])) {
-- 
2.15.1

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