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 <chuck.lever@xxxxxxxxxx>
---
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;
