Target/sbc: Don't use sg as iterator in sbc_verify_read

Because then this sg is passed to sbc_copy_prot which will
hit a protection fault in cases we have more than a single sg.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index ef1a58a..42f18fc 100644 (file)
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -1162,7 +1162,7 @@ sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
 {
        struct se_device *dev = cmd->se_dev;
        struct se_dif_v1_tuple *sdt;
-       struct scatterlist *dsg;
+       struct scatterlist *dsg, *psg = sg;
        sector_t sector = start;
        void *daddr, *paddr;
        int i, j, offset = sg_off;
@@ -1170,14 +1170,14 @@ sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
 
        for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
                daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
-               paddr = kmap_atomic(sg_page(sg)) + sg->offset;
+               paddr = kmap_atomic(sg_page(psg)) + sg->offset;
 
                for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
 
-                       if (offset >= sg->length) {
+                       if (offset >= psg->length) {
                                kunmap_atomic(paddr);
-                               sg = sg_next(sg);
-                               paddr = kmap_atomic(sg_page(sg)) + sg->offset;
+                               psg = sg_next(psg);
+                               paddr = kmap_atomic(sg_page(psg)) + psg->offset;
                                offset = 0;
                        }