Hello, The following program causes a memory leak of an object allocated in lapb_register:
// autogenerated by syzkaller (http://github.com/google/syzkaller) #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <sys/ioctl.h> #include <stdlib.h> #include <linux/tty.h> int main(int argc, char **argv) { int fd, val; fd = open("/dev/ptmx", O_RDWR); val = N_X25; ioctl(fd, TIOCSETD, &val); return 0; } unreferenced object 0xffff880034b943d8 (size 512): comm "softirq", pid 0, jiffies 4294896736 (age 10.460s) hex dump (first 32 bytes): 00 01 00 00 00 00 ad de 00 02 00 00 00 00 ad de ................ c0 a3 d3 35 00 88 ff ff 00 00 00 00 00 00 00 00 ...5............ backtrace: [<ffffffff86680923>] kmemleak_alloc+0x63/0xa0 mm/kmemleak.c:916 [< inline >] kmemleak_alloc_recursive include/linux/kmemleak.h:47 [< inline >] slab_post_alloc_hook mm/slub.c:1337 [< inline >] slab_alloc_node mm/slub.c:2596 [< inline >] slab_alloc mm/slub.c:2604 [<ffffffff8176ae6e>] kmem_cache_alloc_trace+0x1ee/0x350 mm/slub.c:2621 [< inline >] kzalloc include/linux/slab.h:463 [< inline >] lapb_create_cb net/lapb/lapb_iface.c:121 [<ffffffff85ca303a>] lapb_register+0xfa/0x590 net/lapb/lapb_iface.c:158 [< inline >] x25_asy_open drivers/net/wan/x25_asy.c:485 [<ffffffff83fa82d8>] x25_asy_open_tty+0x438/0x760 drivers/net/wan/x25_asy.c:573 [<ffffffff82fbd258>] tty_ldisc_open.isra.2+0x78/0xd0 drivers/tty/tty_ldisc.c:454 [<ffffffff82fbd842>] tty_set_ldisc+0x292/0x8a0 drivers/tty/tty_ldisc.c:561 [< inline >] tiocsetd drivers/tty/tty_io.c:2655 [<ffffffff82fa651e>] tty_ioctl+0xb2e/0x2160 drivers/tty/tty_io.c:2910 [< inline >] vfs_ioctl fs/ioctl.c:43 [<ffffffff8180597c>] do_vfs_ioctl+0x18c/0xfb0 fs/ioctl.c:674 [< inline >] SYSC_ioctl fs/ioctl.c:689 [<ffffffff8180682f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:680 [<ffffffff8669ddb6>] entry_SYSCALL_64_fastpath+0x16/0x7a arch/x86/entry/entry_64.S:185 [<ffffffffffffffff>] 0xffffffffffffffff On commit 23300f657594656e7ebac3130b43460ebc4381cc (Feb 19).
