From: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Date: Sat, 22 Oct 2022 15:35:20 +0800
Subject: [PATCH] cifs: Fix pages leak when writedata alloc failed in
cifs_write_from_iter()
Git-commit: f950c85e782f90702468bba8243cc97a8d0d04b0
References: bsc#1190317
Patch-mainline: v6.1-rc3
There is a kmemleak when writedata alloc failed:
unreferenced object 0xffff888175ae4000 (size 4096):
comm "dd", pid 19419, jiffies 4296028749 (age 739.396s)
hex dump (first 32 bytes):
80 02 b0 04 00 ea ff ff c0 02 b0 04 00 ea ff ff ................
80 22 4c 04 00 ea ff ff c0 22 4c 04 00 ea ff ff ."L......"L.....
backtrace:
[<0000000072fdbb86>] __kmalloc_node+0x50/0x150
[<0000000039faf56f>] __iov_iter_get_pages_alloc+0x605/0xdd0
[<00000000f862a9d4>] iov_iter_get_pages_alloc2+0x3b/0x80
[<000000008f226067>] cifs_write_from_iter+0x2ae/0xe40
[<000000001f78f2f1>] __cifs_writev+0x337/0x5c0
[<00000000257fcef5>] vfs_write+0x503/0x690
[<000000008778a238>] ksys_write+0xb9/0x150
[<00000000ed82047c>] do_syscall_64+0x35/0x80
[<000000003365551d>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
__iov_iter_get_pages_alloc+0x605/0xdd0 is:
want_pages_array at lib/iov_iter.c:1304
(inlined by) __iov_iter_get_pages_alloc at lib/iov_iter.c:1457
If writedata allocate failed, the pages and pagevec should be cleanup.
Fixes: 8c5f9c1ab7cb ("CIFS: Add support for direct I/O write")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
fs/cifs/file.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index d9fbf1ec6029..cd9698209930 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3303,6 +3303,9 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
cifs_uncached_writev_complete);
if (!wdata) {
rc = -ENOMEM;
+ for (i = 0; i < nr_pages; i++)
+ put_page(pagevec[i]);
+ kvfree(pagevec);
add_credits_and_wake_if(server, credits, 0);
break;
}
--
2.35.3