| Message ID | 1500245845.13893.3.camel@primarydata.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sun, Jul 16, 2017 at 10:57:27PM +0000, Trond Myklebust wrote: > > BUG: KASAN: global-out-of-bounds in call_start+0x93/0x100 > > Read of size 8 at addr ffffffff8d582588 by task kworker/0:1/22 > > Does the following patch fix it? Yep, seems to do the trick! Dave
On Sun, Jul 16, 2017 at 8:05 PM, davej@codemonkey.org.uk <davej@codemonkey.org.uk> wrote: > On Sun, Jul 16, 2017 at 10:57:27PM +0000, Trond Myklebust wrote: > > > > BUG: KASAN: global-out-of-bounds in call_start+0x93/0x100 > > > Read of size 8 at addr ffffffff8d582588 by task kworker/0:1/22 > > > > Does the following patch fix it? > > Yep, seems to do the trick! I'm assuming I'll get this fix through a future pull request, and am not applying the patch as-is. Just FYI. Linus
Please pull:
git://linux-nfs.org/~bfields/linux.git tags/nfsd-4.13-1
One fix for a problem introduced in the most recent merge window and
found by Dave Jones and KASAN.
--b.
Trond Myklebust (1):
nfsd: Fix a memory scribble in the callback channel
fs/nfsd/nfs4callback.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
Another NFSv4 KASAN splat, this time from rc3.
==================================================================
BUG: KASAN: use-after-free in nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4]
Read of size 8 at addr ffff8804508af528 by task kworker/2:1/34
CPU: 2 PID: 34 Comm: kworker/2:1 Not tainted 4.13.0-rc3-think+ #1
Workqueue: rpciod rpc_async_schedule [sunrpc]
Call Trace:
dump_stack+0x68/0xa1
print_address_description+0xd9/0x270
kasan_report+0x257/0x370
? nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4]
check_memory_region+0x13a/0x1a0
__asan_loadN+0xf/0x20
nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4]
? nfs4_exchange_id_release+0xb0/0xb0 [nfsv4]
rpc_exit_task+0x69/0x110 [sunrpc]
? rpc_destroy_wait_queue+0x20/0x20 [sunrpc]
? rpc_destroy_wait_queue+0x20/0x20 [sunrpc]
__rpc_execute+0x1a0/0x840 [sunrpc]
? rpc_wake_up_queued_task+0x50/0x50 [sunrpc]
? __lock_is_held+0x9a/0x100
? debug_lockdep_rcu_enabled.part.16+0x1a/0x30
rpc_async_schedule+0x12/0x20 [sunrpc]
process_one_work+0x4d5/0xa70
? flush_delayed_work+0x70/0x70
? lock_acquire+0xfc/0x220
worker_thread+0x88/0x630
? pci_mmcfg_check_reserved+0xc0/0xc0
kthread+0x1a6/0x1f0
? process_one_work+0xa70/0xa70
? kthread_create_on_node+0xc0/0xc0
ret_from_fork+0x27/0x40
Allocated by task 1:
save_stack_trace+0x1b/0x20
save_stack+0x46/0xd0
kasan_kmalloc+0xad/0xe0
kasan_slab_alloc+0x12/0x20
kmem_cache_alloc+0xe0/0x2f0
getname_flags+0x43/0x220
getname+0x12/0x20
do_sys_open+0x14c/0x2b0
SyS_open+0x1e/0x20
do_syscall_64+0xea/0x260
return_from_SYSCALL_64+0x0/0x7a
Freed by task 1:
save_stack_trace+0x1b/0x20
save_stack+0x46/0xd0
kasan_slab_free+0x72/0xc0
kmem_cache_free+0xa8/0x300
putname+0x80/0x90
do_sys_open+0x22f/0x2b0
SyS_open+0x1e/0x20
do_syscall_64+0xea/0x260
return_from_SYSCALL_64+0x0/0x7a
The buggy address belongs to the object at ffff8804508aeac0\x0a which belongs to the cache names_cache of size 4096
The buggy address is located 2664 bytes inside of\x0a 4096-byte region [ffff8804508aeac0, ffff8804508afac0)
The buggy address belongs to the page:
page:ffffea0011422a00 count:1 mapcount:0 mapping: (null) index:0x0
[CONT START] compound_mapcount: 0
flags: 0x8000000000008100(slab|head)
raw: 8000000000008100 0000000000000000 0000000000000000 0000000100070007
raw: ffffea00113d6020 ffffea001136e220 ffff8804664f8040 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8804508af400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8804508af480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8804508af500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8804508af580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8804508af600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
On Mon, Jul 31, 2017 at 8:43 AM, davej@codemonkey.org.uk <davej@codemonkey.org.uk> wrote: > Another NFSv4 KASAN splat, this time from rc3. > > BUG: KASAN: use-after-free in nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4] Ugh. It's really hard to tell what access that it - KASAN doesn't actually give enough information. There's lots of 8-byte accesses there in that function. Any chance of getting the output from ./scripts/faddr2line vmlinux nfs4_exchange_id_done+0x3d7/0x8e0 or something? That would be extremely useful in general for stacktraces, but it's doubly useful for KASAN because most *other* stacktraces tend to have a very limited number of things that can warn (ie there's one or two WARN_ON() calls in a function), but KASAN can have tens or hundreds.. Linus > Read of size 8 at addr ffff8804508af528 by task kworker/2:1/34 > > CPU: 2 PID: 34 Comm: kworker/2:1 Not tainted 4.13.0-rc3-think+ #1 > Workqueue: rpciod rpc_async_schedule [sunrpc] > Call Trace: > dump_stack+0x68/0xa1 > print_address_description+0xd9/0x270 > kasan_report+0x257/0x370 > ? nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4] > check_memory_region+0x13a/0x1a0 > __asan_loadN+0xf/0x20 > nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4] > ? nfs4_exchange_id_release+0xb0/0xb0 [nfsv4] > rpc_exit_task+0x69/0x110 [sunrpc] > ? rpc_destroy_wait_queue+0x20/0x20 [sunrpc] > ? rpc_destroy_wait_queue+0x20/0x20 [sunrpc] > __rpc_execute+0x1a0/0x840 [sunrpc] > ? rpc_wake_up_queued_task+0x50/0x50 [sunrpc] > ? __lock_is_held+0x9a/0x100 > ? debug_lockdep_rcu_enabled.part.16+0x1a/0x30 > rpc_async_schedule+0x12/0x20 [sunrpc] > process_one_work+0x4d5/0xa70 > ? flush_delayed_work+0x70/0x70 > ? lock_acquire+0xfc/0x220 > worker_thread+0x88/0x630 > ? pci_mmcfg_check_reserved+0xc0/0xc0 > kthread+0x1a6/0x1f0 > ? process_one_work+0xa70/0xa70 > ? kthread_create_on_node+0xc0/0xc0 > ret_from_fork+0x27/0x40 > > Allocated by task 1: > save_stack_trace+0x1b/0x20 > save_stack+0x46/0xd0 > kasan_kmalloc+0xad/0xe0 > kasan_slab_alloc+0x12/0x20 > kmem_cache_alloc+0xe0/0x2f0 > getname_flags+0x43/0x220 > getname+0x12/0x20 > do_sys_open+0x14c/0x2b0 > SyS_open+0x1e/0x20 > do_syscall_64+0xea/0x260 > return_from_SYSCALL_64+0x0/0x7a > > Freed by task 1: > save_stack_trace+0x1b/0x20 > save_stack+0x46/0xd0 > kasan_slab_free+0x72/0xc0 > kmem_cache_free+0xa8/0x300 > putname+0x80/0x90 > do_sys_open+0x22f/0x2b0 > SyS_open+0x1e/0x20 > do_syscall_64+0xea/0x260 > return_from_SYSCALL_64+0x0/0x7a > > The buggy address belongs to the object at ffff8804508aeac0\x0a which belongs to the cache names_cache of size 4096 > The buggy address is located 2664 bytes inside of\x0a 4096-byte region [ffff8804508aeac0, ffff8804508afac0) > The buggy address belongs to the page: > page:ffffea0011422a00 count:1 mapcount:0 mapping: (null) index:0x0 > [CONT START] compound_mapcount: 0 > flags: 0x8000000000008100(slab|head) > raw: 8000000000008100 0000000000000000 0000000000000000 0000000100070007 > raw: ffffea00113d6020 ffffea001136e220 ffff8804664f8040 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8804508af400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8804508af480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >>ffff8804508af500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8804508af580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8804508af600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ================================================================== >
On Mon, Jul 31, 2017 at 10:35:45PM -0700, Linus Torvalds wrote: > On Mon, Jul 31, 2017 at 8:43 AM, davej@codemonkey.org.uk > <davej@codemonkey.org.uk> wrote: > > Another NFSv4 KASAN splat, this time from rc3. > > > > BUG: KASAN: use-after-free in nfs4_exchange_id_done+0x3d7/0x8e0 [nfsv4] > > Ugh. It's really hard to tell what access that it - KASAN doesn't > actually give enough information. There's lots of 8-byte accesses > there in that function. > > Any chance of getting the output from > > ./scripts/faddr2line vmlinux nfs4_exchange_id_done+0x3d7/0x8e0 Hm, that points to this.. 7463 /* Save the EXCHANGE_ID verifier session trunk tests */ 7464 memcpy(clp->cl_confirm.data, cdata->args.verifier->data, 7465 sizeof(clp->cl_confirm.data)); Dave
diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c index b45083c0f9ae..49b0a9e7ff18 100644 --- a/fs/nfsd/nfs4callback.c +++ b/fs/nfsd/nfs4callback.c @@ -720,8 +720,8 @@ static const struct rpc_version nfs_cb_version4 = { .counts = nfs4_cb_counts, }; -static const struct rpc_version *nfs_cb_version[] = { - &nfs_cb_version4, +static const struct rpc_version *nfs_cb_version[2] = { + [1] = &nfs_cb_version4, }; static const struct rpc_program cb_program; @@ -795,7 +795,7 @@ static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *c .saddress = (struct sockaddr *) &conn->cb_saddr, .timeout = &timeparms, .program = &cb_program, - .version = 0, + .version = 1, .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), }; struct rpc_clnt *client;