linux_dsm_epyc7002/net/sunrpc
Dave Wysochanski 518416a75c SUNRPC: Handle 0 length opaque XDR object data properly
[ Upstream commit e4a7d1f7707eb44fd953a31dd59eff82009d879c ]

When handling an auth_gss downcall, it's possible to get 0-length
opaque object for the acceptor.  In the case of a 0-length XDR
object, make sure simple_get_netobj() fills in dest->data = NULL,
and does not continue to kmemdup() which will set
dest->data = ZERO_SIZE_PTR for the acceptor.

The trace event code can handle NULL but not ZERO_SIZE_PTR for a
string, and so without this patch the rpcgss_context trace event
will crash the kernel as follows:

[  162.887992] BUG: kernel NULL pointer dereference, address: 0000000000000010
[  162.898693] #PF: supervisor read access in kernel mode
[  162.900830] #PF: error_code(0x0000) - not-present page
[  162.902940] PGD 0 P4D 0
[  162.904027] Oops: 0000 [#1] SMP PTI
[  162.905493] CPU: 4 PID: 4321 Comm: rpc.gssd Kdump: loaded Not tainted 5.10.0 #133
[  162.908548] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[  162.910978] RIP: 0010:strlen+0x0/0x20
[  162.912505] Code: 48 89 f9 74 09 48 83 c1 01 80 39 00 75 f7 31 d2 44 0f b6 04 16 44 88 04 11 48 83 c2 01 45 84 c0 75 ee c3 0f 1f 80 00 00 00 00 <80> 3f 00 74 10 48 89 f8 48 83 c0 01 80 38 00 75 f7 48 29 f8 c3 31
[  162.920101] RSP: 0018:ffffaec900c77d90 EFLAGS: 00010202
[  162.922263] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000fffde697
[  162.925158] RDX: 000000000000002f RSI: 0000000000000080 RDI: 0000000000000010
[  162.928073] RBP: 0000000000000010 R08: 0000000000000e10 R09: 0000000000000000
[  162.930976] R10: ffff8e698a590cb8 R11: 0000000000000001 R12: 0000000000000e10
[  162.933883] R13: 00000000fffde697 R14: 000000010034d517 R15: 0000000000070028
[  162.936777] FS:  00007f1e1eb93700(0000) GS:ffff8e6ab7d00000(0000) knlGS:0000000000000000
[  162.940067] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  162.942417] CR2: 0000000000000010 CR3: 0000000104eba000 CR4: 00000000000406e0
[  162.945300] Call Trace:
[  162.946428]  trace_event_raw_event_rpcgss_context+0x84/0x140 [auth_rpcgss]
[  162.949308]  ? __kmalloc_track_caller+0x35/0x5a0
[  162.951224]  ? gss_pipe_downcall+0x3a3/0x6a0 [auth_rpcgss]
[  162.953484]  gss_pipe_downcall+0x585/0x6a0 [auth_rpcgss]
[  162.955953]  rpc_pipe_write+0x58/0x70 [sunrpc]
[  162.957849]  vfs_write+0xcb/0x2c0
[  162.959264]  ksys_write+0x68/0xe0
[  162.960706]  do_syscall_64+0x33/0x40
[  162.962238]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  162.964346] RIP: 0033:0x7f1e1f1e57df

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13 13:55:12 +01:00
..
auth_gss SUNRPC: Handle 0 length opaque XDR object data properly 2021-02-13 13:55:12 +01:00
xprtrdma xprtrdma: Fix XDRBUF_SPARSE_PAGES support 2020-12-30 11:54:15 +01:00
addr.c net: sunrpc: interpret the return value of kstrtou32 correctly 2021-01-19 18:27:33 +01:00
auth_null.c SUNRPC: Add rpc_auth::au_ralign field 2019-02-14 11:48:36 -05:00
auth_unix.c SUNRPC: Use the client user namespace when encoding creds 2019-04-26 16:24:32 -04:00
auth.c sunrpc: add missing newline when printing parameter 'auth_hashtable_size' by sysfs 2020-06-11 13:33:48 -04:00
backchannel_rqst.c The one new feature this time, from Anna Schumaker, is READ_PLUS, which 2020-10-22 09:44:27 -07:00
cache.c sunrpc: raise kernel RPC channel buffer size 2020-10-20 13:21:30 -04:00
clnt.c SUNRPC: Clean up call_bind_status() observability 2020-09-21 10:21:09 -04:00
debugfs.c net: sunrpc: Fix 'snprintf' return value check in 'do_xprt_debugfs' 2020-12-30 11:53:30 +01:00
Kconfig SUNRPC: remove RC4-HMAC-MD5 support from KerberosV 2020-09-11 14:39:15 +10:00
Makefile SUNRPC: remove generic cred code. 2018-12-19 13:52:46 -05:00
netns.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rpc_pipe.c sunrpc: destroy rpc_inode_cachep after unregister_filesystem 2020-07-17 13:12:44 -04:00
rpcb_clnt.c SUNRPC: Replace rpcbind dprintk call sites with tracepoints 2020-09-21 10:21:09 -04:00
sched.c SUNRPC: rpc_wake_up() should wake up tasks in the correct order 2020-12-30 11:53:30 +01:00
socklib.c skb_copy_and_csum_bits(): don't bother with the last argument 2020-08-20 15:45:13 -04:00
socklib.h SUNRPC: Refactor xs_sendpages() 2020-03-16 12:04:33 -04:00
stats.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
sunrpc_syms.c sunrpc: check that domain table is empty at module unload. 2020-05-28 18:15:00 -04:00
sunrpc.h Replace HTTP links with HTTPS ones: NFS, SUNRPC, and LOCKD clients 2020-09-21 10:21:10 -04:00
svc_xprt.c NFS Client Updates for Linux 5.8 2020-06-11 12:22:41 -07:00
svc.c Merge branch 'nfsd-5.8' of git://linux-nfs.org/~cel/cel-2.6 into for-5.8-incoming 2020-05-21 10:58:15 -04:00
svcauth_unix.c sunrpc: Remove unused function ip_map_update 2020-05-06 16:00:11 -04:00
svcauth.c sunrpc: check that domain table is empty at module unload. 2020-05-28 18:15:00 -04:00
svcsock.c SUNRPC: Fix NFS READs that start at non-page-aligned offsets 2021-02-10 09:29:13 +01:00
sysctl.c net/sunrpc: fix useless comparison in proc_do_xprt() 2020-11-08 16:28:25 -05:00
timer.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
xdr.c The one new feature this time, from Anna Schumaker, is READ_PLUS, which 2020-10-22 09:44:27 -07:00
xprt.c SUNRPC: xprt_load_transport() needs to support the netid "rdma6" 2020-12-30 11:53:30 +01:00
xprtmultipath.c SUNRPC: Optimise transport balancing code 2019-07-18 14:43:52 -04:00
xprtsock.c sunrpc: fix xs_read_xdr_buf for partial pages receive 2020-12-30 11:53:53 +01:00