The patch titled
Subject: ipc,sem: prevent releasing RCU read lock twice in semctl_main
has been added to the -mm tree. Its filename is
ipcsem-do-not-hold-ipc-lock-more-than-necessary-fix.patch
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------------------------------------------------------
From: Sasha Levin <sasha.levin@xxxxxxxxxx>
Subject: ipc,sem: prevent releasing RCU read lock twice in semctl_main
We will release RCU read lock twice if the sem id passed from userspace is
not within the legal range in semctl_main.
Reviewed-by: Rik van Riel <riel@xxxxxxxxxx>
Reviewed-by: Davidlohr Bueso <davidlohr.bueso@xxxxxx>
Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
ipc/sem.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff -puN ipc/sem.c~ipcsem-do-not-hold-ipc-lock-more-than-necessary-fix ipc/sem.c
--- a/ipc/sem.c~ipcsem-do-not-hold-ipc-lock-more-than-necessary-fix
+++ a/ipc/sem.c
@@ -1098,8 +1098,10 @@ static int semctl_main(struct ipc_namesp
/* GETVAL, GETPID, GETNCTN, GETZCNT: fall-through */
}
err = -EINVAL;
- if(semnum < 0 || semnum >= nsems)
- goto out_unlock;
+ if(semnum < 0 || semnum >= nsems) {
+ rcu_read_unlock();
+ goto out_wakeup;
+ }
spin_lock(&sma->sem_perm.lock);
curr = &sma->sem_base[semnum];
_
Patches currently in -mm which might be from sasha.levin@xxxxxxxxxx are
linux-next.patch
watchdog-trigger-all-cpu-backtrace-when-locked-up-and-going-to-panic.patch
ipcsem-do-not-hold-ipc-lock-more-than-necessary-fix.patch
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