From 82ea5a1742e22638db3e3bb812e2e2b1eaf6b661 Mon Sep 17 00:00:00 2001 From: Jouni Hogander Date: Wed, 13 Nov 2019 13:45:02 +0200 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 --- 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 436dd78c396a..2901b7db9d2e 100644 --- a/drivers/net/slip/slip.c +++ b/drivers/net/slip/slip.c @@ -859,6 +859,7 @@ err_free_chan: sl->tty = NULL; tty->disc_data = NULL; clear_bit(SLF_INUSE, &sl->flags); + free_netdev(sl->dev); err_exit: rtnl_unlock();