Wind River Support Network

Description

In the Linux kernel, the following vulnerability has been resolved:  nfsd: Fix cred ref leak in nfsd_nl_threads_set_doit().  syzbot reported memory leak of struct cred. [0]  nfsd_nl_threads_set_doit() passes get_current_cred() to nfsd_svc(), but put_cred() is not called after that.  The cred is finally passed down to _svc_xprt_create(), which calls get_cred() with the cred for struct svc_xprt.  The ownership of the refcount by get_current_cred() is not transferred to anywhere and is just leaked.  nfsd_svc() is also called from write_threads(), but it does not bump file->f_cred there.  nfsd_nl_threads_set_doit() is called from sendmsg() and current->cred does not go away.  Let's use current_cred() in nfsd_nl_threads_set_doit().  [0]: BUG: memory leak unreferenced object 0xffff888108b89480 (size 184):   comm "syz-executor", pid 5994, jiffies 4294943386   hex dump (first 32 bytes):     01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................   backtrace (crc 369454a7):     kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]     slab_post_alloc_hook mm/slub.c:4958 [inline]     slab_alloc_node mm/slub.c:5263 [inline]     kmem_cache_alloc_noprof+0x412/0x580 mm/slub.c:5270     prepare_creds+0x22/0x600 kernel/cred.c:185     copy_creds+0x44/0x290 kernel/cred.c:286     copy_process+0x7a7/0x2870 kernel/fork.c:2086     kernel_clone+0xac/0x6e0 kernel/fork.c:2651     __do_sys_clone+0x7f/0xb0 kernel/fork.c:2792     do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]     do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94     entry_SYSCALL_64_after_hwframe+0x77/0x7f