From 390395604fd4d2f3487f8d673c2c2776f8910bca Mon Sep 17 00:00:00 2001 From: Jouni Hogander Date: Thu, 21 Nov 2019 13:32:02 +0800 Subject: [PATCH] slip: Fix memory leak in slip_open error path [ Upstream commit 3b5a39979dafea9d0cd69c7ae06088f7a84cdafa ] Driver/net/can/slcan.c is derived from slip.c. Memory leak was detected by Syzkaller in slcan. Same issue exists in slip.c and this patch is addressing the leak in slip.c. Here is the slcan memory leak trace reported by Syzkaller: BUG: memory leak unreferenced object 0xffff888067f65500 (size 4096): comm "syz-executor043", pid 454, jiffies 4294759719 (age 11.930s) hex dump (first 32 bytes): 73 6c 63 61 6e 30 00 00 00 00 00 00 00 00 00 00 slcan0.......... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000a06eec0d>] __kmalloc+0x18b/0x2c0 [<0000000083306e66>] kvmalloc_node+0x3a/0xc0 [<000000006ac27f87>] alloc_netdev_mqs+0x17a/0x1080 [<0000000061a996c9>] slcan_open+0x3ae/0x9a0 [<000000001226f0f9>] tty_ldisc_open.isra.1+0x76/0xc0 [<0000000019289631>] tty_set_ldisc+0x28c/0x5f0 [<000000004de5a617>] tty_ioctl+0x48d/0x1590 [<00000000daef496f>] do_vfs_ioctl+0x1c7/0x1510 [<0000000059068dbc>] ksys_ioctl+0x99/0xb0 [<000000009a6eb334>] __x64_sys_ioctl+0x78/0xb0 [<0000000053d0332e>] do_syscall_64+0x16f/0x580 [<0000000021b83b99>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [<000000008ea75434>] 0xfffffffffffffff Cc: "David S. Miller" Cc: Oliver Hartkopp Cc: Lukas Bulwahn Signed-off-by: Jouni Hogander Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yang Yingliang --- drivers/net/slip/slip.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/slip/slip.c b/drivers/net/slip/slip.c index b008266e91ea..a5874059da9d 100644 --- a/drivers/net/slip/slip.c +++ b/drivers/net/slip/slip.c @@ -855,6 +855,7 @@ static int slip_open(struct tty_struct *tty) sl->tty = NULL; tty->disc_data = NULL; clear_bit(SLF_INUSE, &sl->flags); + free_netdev(sl->dev); err_exit: rtnl_unlock(); -- GitLab