From: Takeshi Misawa <jeliantsurux@xxxxxxxxx>
commit fc0494ead6398609c49afa37bc949b61c5c16b91 upstream.
If qrtr_endpoint_register() failed, tun is leaked.
Fix this, by freeing tun in error path.
syzbot report:
BUG: memory leak
unreferenced object 0xffff88811848d680 (size 64):
comm "syz-executor684", pid 10171, jiffies 4294951561 (age 26.070s)
hex dump (first 32 bytes):
80 dd 0a 84 ff ff ff ff 00 00 00 00 00 00 00 00 ................
90 d6 48 18 81 88 ff ff 90 d6 48 18 81 88 ff ff ..H.......H.....
backtrace:
[<0000000018992a50>] kmalloc include/linux/slab.h:552 [inline]
[<0000000018992a50>] kzalloc include/linux/slab.h:682 [inline]
[<0000000018992a50>] qrtr_tun_open+0x22/0x90 net/qrtr/tun.c:35
[<0000000003a453ef>] misc_open+0x19c/0x1e0 drivers/char/misc.c:141
[<00000000dec38ac8>] chrdev_open+0x10d/0x340 fs/char_dev.c:414
[<0000000079094996>] do_dentry_open+0x1e6/0x620 fs/open.c:817
[<000000004096d290>] do_open fs/namei.c:3252 [inline]
[<000000004096d290>] path_openat+0x74a/0x1b00 fs/namei.c:3369
[<00000000b8e64241>] do_filp_open+0xa0/0x190 fs/namei.c:3396
[<00000000a3299422>] do_sys_openat2+0xed/0x230 fs/open.c:1172
[<000000002c1bdcef>] do_sys_open fs/open.c:1188 [inline]
[<000000002c1bdcef>] __do_sys_openat fs/open.c:1204 [inline]
[<000000002c1bdcef>] __se_sys_openat fs/open.c:1199 [inline]
[<000000002c1bdcef>] __x64_sys_openat+0x7f/0xe0 fs/open.c:1199
[<00000000f3a5728f>] do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
[<000000004b38b7ec>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 28fb4e59a47d ("net: qrtr: Expose tunneling endpoint to user space")
Reported-by: syzbot+5d6e4af21385f5cfc56a@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Takeshi Misawa <jeliantsurux@xxxxxxxxx>
Link: https://lore.kernel.org/r/20210221234427.GA2140@DESKTOP
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/qrtr/tun.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
--- a/net/qrtr/tun.c
+++ b/net/qrtr/tun.c
@@ -31,6 +31,7 @@ static int qrtr_tun_send(struct qrtr_end
static int qrtr_tun_open(struct inode *inode, struct file *filp)
{
struct qrtr_tun *tun;
+ int ret;
tun = kzalloc(sizeof(*tun), GFP_KERNEL);
if (!tun)
@@ -43,7 +44,16 @@ static int qrtr_tun_open(struct inode *i
filp->private_data = tun;
- return qrtr_endpoint_register(&tun->ep, QRTR_EP_NID_AUTO);
+ ret = qrtr_endpoint_register(&tun->ep, QRTR_EP_NID_AUTO);
+ if (ret)
+ goto out;
+
+ return 0;
+
+out:
+ filp->private_data = NULL;
+ kfree(tun);
+ return ret;
}
static ssize_t qrtr_tun_read_iter(struct kiocb *iocb, struct iov_iter *to)
