--- /dev/null
+From 8bd90b6ae7856dd5000b75691d905b39b9ea5d6b Mon Sep 17 00:00:00 2001
+From: Jingbo Xu <jefflexu@linux.alibaba.com>
+Date: Tue, 14 Nov 2023 15:07:04 +0800
+Subject: erofs: fix NULL dereference of dif->bdev_handle in fscache mode
+
+From: Jingbo Xu <jefflexu@linux.alibaba.com>
+
+commit 8bd90b6ae7856dd5000b75691d905b39b9ea5d6b upstream.
+
+Avoid NULL dereference of dif->bdev_handle, as dif->bdev_handle is NULL
+in fscache mode.
+
+ BUG: kernel NULL pointer dereference, address: 0000000000000000
+ RIP: 0010:erofs_map_dev+0xbd/0x1c0
+ Call Trace:
+ <TASK>
+ erofs_fscache_data_read_slice+0xa7/0x340
+ erofs_fscache_data_read+0x11/0x30
+ erofs_fscache_readahead+0xd9/0x100
+ read_pages+0x47/0x1f0
+ page_cache_ra_order+0x1e5/0x270
+ filemap_get_pages+0xf2/0x5f0
+ filemap_read+0xb8/0x2e0
+ vfs_read+0x18d/0x2b0
+ ksys_read+0x53/0xd0
+ do_syscall_64+0x42/0xf0
+ entry_SYSCALL_64_after_hwframe+0x6e/0x76
+
+Reported-by: Yiqun Leng <yqleng@linux.alibaba.com>
+Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=7245
+Fixes: 49845720080d ("erofs: Convert to use bdev_open_by_path()")
+Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
+Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
+Reviewed-by: Yue Hu <huyue2@coolpad.com>
+Reviewed-by: Chao Yu <chao@kernel.org>
+Link: https://lore.kernel.org/r/20231114070704.23398-1-jefflexu@linux.alibaba.com
+Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
+Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ fs/erofs/data.c | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+--- a/fs/erofs/data.c
++++ b/fs/erofs/data.c
+@@ -222,7 +222,7 @@ int erofs_map_dev(struct super_block *sb
+ up_read(&devs->rwsem);
+ return 0;
+ }
+- map->m_bdev = dif->bdev_handle->bdev;
++ map->m_bdev = dif->bdev_handle ? dif->bdev_handle->bdev : NULL;
+ map->m_daxdev = dif->dax_dev;
+ map->m_dax_part_off = dif->dax_part_off;
+ map->m_fscache = dif->fscache;
+@@ -240,7 +240,8 @@ int erofs_map_dev(struct super_block *sb
+ if (map->m_pa >= startoff &&
+ map->m_pa < startoff + length) {
+ map->m_pa -= startoff;
+- map->m_bdev = dif->bdev_handle->bdev;
++ map->m_bdev = dif->bdev_handle ?
++ dif->bdev_handle->bdev : NULL;
+ map->m_daxdev = dif->dax_dev;
+ map->m_dax_part_off = dif->dax_part_off;
+ map->m_fscache = dif->fscache;