6.6-stable review patch. If anyone has any objections, please let me know.
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From: Scott Mayhew smayhew@redhat.com
[ Upstream commit a10a9233073d984b239e22358ba21825e27e2e88 ]
The subjective cred (task->cred) can potentially be overridden and subsquently freed in non-RCU context, which could lead to a panic if we try to use it in cred_fscmp(). Use __task_cred(), which returns the objective cred (task->real_cred) instead.
Fixes: 0eb43812c027 ("NFS: Clear the file access cache upon login") Fixes: 5e9a7b9c2ea1 ("NFS: Fix up a sparse warning")
Signed-off-by: Scott Mayhew smayhew@redhat.com Signed-off-by: Anna Schumaker Anna.Schumaker@Netapp.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfs/dir.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index e6a51fd94fea..9fc5061d51b2 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -2968,7 +2968,7 @@ static u64 nfs_access_login_time(const struct task_struct *task, rcu_read_lock(); for (;;) { parent = rcu_dereference(task->real_parent); - pcred = rcu_dereference(parent->cred); + pcred = __task_cred(parent); if (parent == task || cred_fscmp(pcred, cred) != 0) break; task = parent;