linux-stable/net/rds
Sabyrzhan Tasbolatov 99996cd558 net/rds: restrict iovecs length for RDS_CMSG_RDMA_ARGS
commit a11148e6fc upstream.

syzbot found WARNING in rds_rdma_extra_size [1] when RDS_CMSG_RDMA_ARGS
control message is passed with user-controlled
0x40001 bytes of args->nr_local, causing order >= MAX_ORDER condition.

The exact value 0x40001 can be checked with UIO_MAXIOV which is 0x400.
So for kcalloc() 0x400 iovecs with sizeof(struct rds_iovec) = 0x10
is the closest limit, with 0x10 leftover.

Same condition is currently done in rds_cmsg_rdma_args().

[1] WARNING: mm/page_alloc.c:5011
[..]
Call Trace:
 alloc_pages_current+0x18c/0x2a0 mm/mempolicy.c:2267
 alloc_pages include/linux/gfp.h:547 [inline]
 kmalloc_order+0x2e/0xb0 mm/slab_common.c:837
 kmalloc_order_trace+0x14/0x120 mm/slab_common.c:853
 kmalloc_array include/linux/slab.h:592 [inline]
 kcalloc include/linux/slab.h:621 [inline]
 rds_rdma_extra_size+0xb2/0x3b0 net/rds/rdma.c:568
 rds_rm_size net/rds/send.c:928 [inline]

Reported-by: syzbot+1bd2b07f93745fa38425@syzkaller.appspotmail.com
Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Link: https://lore.kernel.org/r/20210201203233.1324704-1-snovitoll@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-17 10:35:19 +01:00
..
af_rds.c
bind.c
cong.c
connection.c
ib.c
ib.h
ib_cm.c
ib_fmr.c
ib_frmr.c
ib_mr.h
ib_rdma.c
ib_recv.c
ib_ring.c
ib_send.c
ib_stats.c
ib_sysctl.c
info.c
info.h
Kconfig
loop.c
loop.h
Makefile
message.c
page.c
rdma.c net/rds: restrict iovecs length for RDS_CMSG_RDMA_ARGS 2021-02-17 10:35:19 +01:00
rdma_transport.c
rdma_transport.h
rds.h
rds_single_path.h
recv.c
send.c
stats.c
sysctl.c
tcp.c
tcp.h
tcp_connect.c
tcp_listen.c
tcp_recv.c
tcp_send.c
tcp_stats.c
threads.c
transport.c