iscsi-target: Fix iscsit_alloc_buffs() failure cases

commit d335e6054db616bce3f040e659fa38440518ad1d upstream.

Make iscsit_alloc_buffs() failure case for page_alloc_failed use correct
__free_page() SGL pointer, and return -ENOMEM for iscsit_allocate_iovecs
failure to push se_cmd->t_mem_sg release into iscsit_release_cmd()
callback during iscsit_add_reject_from_cmd() connection reset.

Also drop cmd->t_mem_sg = NULL assignment from page_alloc_failed
failure case.

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index 03d35286365d5021115cb848663282ea5f27ae22..0842cc74a053f4f1fd3169ead715820304d8a01a 100644 (file)
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -781,7 +781,7 @@ static int iscsit_alloc_buffs(struct iscsi_cmd *cmd)
        struct scatterlist *sgl;
        u32 length = cmd->se_cmd.data_length;
        int nents = DIV_ROUND_UP(length, PAGE_SIZE);
-       int i = 0, ret;
+       int i = 0, j = 0, ret;
        /*
         * If no SCSI payload is present, allocate the default iovecs used for
         * iSCSI PDU Header
@@ -822,17 +822,15 @@ static int iscsit_alloc_buffs(struct iscsi_cmd *cmd)
         */
         ret = iscsit_allocate_iovecs(cmd);
         if (ret < 0)
-               goto page_alloc_failed;
+               return -ENOMEM;
 
        return 0;
 
 page_alloc_failed:
-       while (i >= 0) {
-               __free_page(sg_page(&sgl[i]));
-               i--;
-       }
-       kfree(cmd->t_mem_sg);
-       cmd->t_mem_sg = NULL;
+       while (j < i)
+               __free_page(sg_page(&sgl[j++]));
+
+       kfree(sgl);
        return -ENOMEM;
 }