compress/qat: fix out-of-bounds write

QAT array for sgls in intermediate buffer structure
was #defined to 1, but setup code hardcoded as if 2 buffers
so causing out of bounds write. Reworked to loop correctly
using #define.

Fixes: a124830a6f00 ("compress/qat: enable dynamic huffman encoding")

Reported-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Signed-off-by: Fiona Trahe <fiona.trahe@intel.com>
Tested-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Tomasz Jozwiak <tomaszx.jozwiak@intel.com>

diff --git a/drivers/compress/qat/qat_comp_pmd.c b/drivers/compress/qat/qat_comp_pmd.c
index 01dd736..ea93077 100644 (file)
--- a/drivers/compress/qat/qat_comp_pmd.c
+++ b/drivers/compress/qat/qat_comp_pmd.c
@@ -165,11 +165,14 @@ qat_comp_setup_inter_buffers(struct qat_comp_dev_private *comp_dev,
        }
 
        /* Create a memzone to hold intermediate buffers and associated
-        * meta-data needed by the firmware. The memzone contains:
+        * meta-data needed by the firmware. The memzone contains 3 parts:
         *  - a list of num_im_sgls physical pointers to sgls
-        *  - the num_im_sgl sgl structures, each pointing to 2 flat buffers
-        *  - the flat buffers: num_im_sgl * 2
-        * where num_im_sgls depends on the hardware generation of the device
+        *  - the num_im_sgl sgl structures, each pointing to
+        *    QAT_NUM_BUFS_IN_IM_SGL flat buffers
+        *  - the flat buffers: num_im_sgl * QAT_NUM_BUFS_IN_IM_SGL
+        *    buffers, each of buff_size
+        * num_im_sgls depends on the hardware generation of the device
+        * buff_size comes from the user via the config file
         */
 
        size_of_ptr_array = num_im_sgls * sizeof(phys_addr_t);
@@ -202,30 +205,31 @@ qat_comp_setup_inter_buffers(struct qat_comp_dev_private *comp_dev,
                    offset_of_sgls + i * sizeof(struct qat_inter_sgl);
                struct qat_inter_sgl *sgl =
                    (struct qat_inter_sgl *)(mz_start + curr_sgl_offset);
+               int lb;
                array_of_pointers->pointer[i] = mz_start_phys + curr_sgl_offset;
 
                sgl->num_bufs = QAT_NUM_BUFS_IN_IM_SGL;
                sgl->num_mapped_bufs = 0;
                sgl->resrvd = 0;
-               sgl->buffers[0].addr = mz_start_phys + offset_of_flat_buffs +
-                       ((i * QAT_NUM_BUFS_IN_IM_SGL) * buff_size);
-               sgl->buffers[0].len = buff_size;
-               sgl->buffers[0].resrvd = 0;
-               sgl->buffers[1].addr = mz_start_phys + offset_of_flat_buffs +
-                       (((i * QAT_NUM_BUFS_IN_IM_SGL) + 1) * buff_size);
-               sgl->buffers[1].len = buff_size;
-               sgl->buffers[1].resrvd = 0;
 
 #if QAT_IM_BUFFER_DEBUG
                QAT_LOG(DEBUG, "  : phys addr of sgl[%i] in array_of_pointers"
-                           "= 0x%"PRIx64, i, array_of_pointers->pointer[i]);
+                       " = 0x%"PRIx64, i, array_of_pointers->pointer[i]);
                QAT_LOG(DEBUG, "  : virt address of sgl[%i] = %p", i, sgl);
-               QAT_LOG(DEBUG, "  : sgl->buffers[0].addr = 0x%"PRIx64", len=%d",
-                       sgl->buffers[0].addr, sgl->buffers[0].len);
-               QAT_LOG(DEBUG, "  : sgl->buffers[1].addr = 0x%"PRIx64", len=%d",
-                       sgl->buffers[1].addr, sgl->buffers[1].len);
+#endif
+               for (lb = 0; lb < QAT_NUM_BUFS_IN_IM_SGL; lb++) {
+                       sgl->buffers[lb].addr =
+                         mz_start_phys + offset_of_flat_buffs +
+                         (((i * QAT_NUM_BUFS_IN_IM_SGL) + lb) * buff_size);
+                       sgl->buffers[lb].len = buff_size;
+                       sgl->buffers[lb].resrvd = 0;
+#if QAT_IM_BUFFER_DEBUG
+                       QAT_LOG(DEBUG,
+                         "  : sgl->buffers[%d].addr = 0x%"PRIx64", len=%d",
+                         lb, sgl->buffers[lb].addr, sgl->buffers[lb].len);
 #endif
                }
+       }
 #if QAT_IM_BUFFER_DEBUG
        QAT_DP_HEXDUMP_LOG(DEBUG,  "IM buffer memzone start:",
                        mz_start, offset_of_flat_buffs + 32);