From f012e95b377c73c0283f009823c633104dedb337 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 1 Jun 2022 12:46:52 -0400 Subject: [PATCH] SUNRPC: Trap RDMA segment overflows Prevent svc_rdma_build_writes() from walking off the end of a Write chunk's segment array. Caught with KASAN. The test that this fix replaces is invalid, and might have been left over from an earlier prototype of the PCL work. Fixes: 7a1cbfa18059 ("svcrdma: Use parsed chunk lists to construct RDMA Writes") Signed-off-by: Chuck Lever --- net/sunrpc/xprtrdma/svc_rdma_rw.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c index 5f0155fdefc7..11cf7c646644 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_rw.c +++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c @@ -478,10 +478,10 @@ svc_rdma_build_writes(struct svc_rdma_write_info *info, unsigned int write_len; u64 offset; - seg = &info->wi_chunk->ch_segments[info->wi_seg_no]; - if (!seg) + if (info->wi_seg_no >= info->wi_chunk->ch_segcount) goto out_overflow; + seg = &info->wi_chunk->ch_segments[info->wi_seg_no]; write_len = min(remaining, seg->rs_length - info->wi_seg_off); if (!write_len) goto out_overflow;