4.20-stable review patch. If anyone has any objections, please let me know.
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From: Michael J. Ruhl michael.j.ruhl@intel.com
commit dbc2970caef74e8ff41923d302aa6fb5a4812d0e upstream.
An incorrect sge sizing in the HFI PIO path will cause an OOPs similar to this:
BUG: unable to handle kernel NULL pointer dereference at (null) IP: [] hfi1_verbs_send_pio+0x3d8/0x530 [hfi1] PGD 0 Oops: 0000 1 SMP Call Trace: ? hfi1_verbs_send_dma+0xad0/0xad0 [hfi1] hfi1_verbs_send+0xdf/0x250 [hfi1] ? make_rc_ack+0xa80/0xa80 [hfi1] hfi1_do_send+0x192/0x430 [hfi1] hfi1_do_send_from_rvt+0x10/0x20 [hfi1] rvt_post_send+0x369/0x820 [rdmavt] ib_uverbs_post_send+0x317/0x570 [ib_uverbs] ib_uverbs_write+0x26f/0x420 [ib_uverbs] ? security_file_permission+0x21/0xa0 vfs_write+0xbd/0x1e0 ? mntput+0x24/0x40 SyS_write+0x7f/0xe0 system_call_fastpath+0x16/0x1b
Fix by adding the missing sizing check to correctly determine the sge length.
Fixes: 7724105686e7 ("IB/hfi1: add driver files") Reviewed-by: Mike Marciniszyn mike.marciniszyn@intel.com Signed-off-by: Michael J. Ruhl michael.j.ruhl@intel.com Signed-off-by: Dennis Dalessandro dennis.dalessandro@intel.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/infiniband/hw/hfi1/verbs.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/infiniband/hw/hfi1/verbs.c +++ b/drivers/infiniband/hw/hfi1/verbs.c @@ -919,6 +919,8 @@ int hfi1_verbs_send_pio(struct rvt_qp *q
if (slen > len) slen = len; + if (slen > ss->sge.sge_length) + slen = ss->sge.sge_length; rvt_update_sge(ss, slen, false); seg_pio_copy_mid(pbuf, addr, slen); len -= slen;