[PATCH] mm/shmem.c: don't set 'seals' to 'F_SEAL_SEAL' in shmem_get_inode

From: yu kuai
Date: Tue Nov 26 2019 - 22:39:57 EST


'seals' is set to 'F_SEAL_SEAL' in shmem_get_inode, which means "prevent
further seals from being set", thus sealing API will be useless and many
code in shmem.c will never be reached. For example:

shmem_setattr
if ((newsize < oldsize && (info->seals & F_SEAL_SHRINK)) ||
(newsize > oldsize && (info->seals & F_SEAL_GROW)))
return -EPERM;

So, initialize 'seals' to zero is more reasonable.

Signed-off-by: yu kuai <yukuai3@xxxxxxxxxx>
---
mm/shmem.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index 165fa6332993..7b032b347bda 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2256,7 +2256,6 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
memset(info, 0, (char *)inode - (char *)info);
spin_lock_init(&info->lock);
atomic_set(&info->stop_eviction, 0);
- info->seals = F_SEAL_SEAL;
info->flags = flags & VM_NORESERVE;
INIT_LIST_HEAD(&info->shrinklist);
INIT_LIST_HEAD(&info->swaplist);
--
2.17.2