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| author | Sabyrzhan Tasbolatov <snovitoll@gmail.com> | 2021-02-02 02:32:33 +0600 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2021-02-02 08:44:08 -0800 |
| commit | a11148e6fcce2ae53f47f0a442d098d860b4f7db (patch) | |
| tree | 9964a0deb7797ffa5a05e0fb488e16c889528f11 /net/rds | |
| parent | 43f4a20a1266d393840ce010f547486d14cc0071 (diff) | |
| download | linux-a11148e6fcce2ae53f47f0a442d098d860b4f7db.tar.bz2 | |
net/rds: restrict iovecs length for RDS_CMSG_RDMA_ARGS
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>
Diffstat (limited to 'net/rds')
| -rw-r--r-- | net/rds/rdma.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/rds/rdma.c b/net/rds/rdma.c index 1d0afb1dd77b..6f1a50d50d06 100644 --- a/net/rds/rdma.c +++ b/net/rds/rdma.c @@ -565,6 +565,9 @@ int rds_rdma_extra_size(struct rds_rdma_args *args, if (args->nr_local == 0) return -EINVAL; + if (args->nr_local > UIO_MAXIOV) + return -EMSGSIZE; + iov->iov = kcalloc(args->nr_local, sizeof(struct rds_iovec), GFP_KERNEL); |