[dpdk-dev] [PATCH v2] mem: fix incorrect munmap in error unwind

[Stephen Hemminger]

The loop to unwind existing mmaps was only unmapping the
first segment and the error paths after mmap() were not
doing munmap of the current segment.

Fixes: 66cc45e293ed ("mem: replace memseg with memseg lists")
Cc: anatoly.bura...@intel.com
Cc: sta...@dpdk.org
Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
Acked-by: Anatoly Burakov <anatoly.bura...@intel.com>
---
v2 - incorporate feedback from David Marchand
     fix missing munmap of current segment

 lib/librte_eal/linux/eal/eal_memory.c | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/lib/librte_eal/linux/eal/eal_memory.c 
b/lib/librte_eal/linux/eal/eal_memory.c
index 43e4ffc757bd..5604c2a7c04d 100644
--- a/lib/librte_eal/linux/eal/eal_memory.c
+++ b/lib/librte_eal/linux/eal/eal_memory.c
@@ -1928,7 +1928,7 @@ eal_legacy_hugepage_attach(void)
                if (flock(fd, LOCK_SH) < 0) {
                        RTE_LOG(DEBUG, EAL, "%s(): Locking file failed: %s\n",
                                __func__, strerror(errno));
-                       goto fd_error;
+                       goto mmap_error;
                }
 
                /* find segment data */
@@ -1936,13 +1936,13 @@ eal_legacy_hugepage_attach(void)
                if (msl == NULL) {
                        RTE_LOG(DEBUG, EAL, "%s(): Cannot find memseg list\n",
                                __func__);
-                       goto fd_error;
+                       goto mmap_error;
                }
                ms = rte_mem_virt2memseg(map_addr, msl);
                if (ms == NULL) {
                        RTE_LOG(DEBUG, EAL, "%s(): Cannot find memseg\n",
                                __func__);
-                       goto fd_error;
+                       goto mmap_error;
                }
 
                msl_idx = msl - mcfg->memsegs;
@@ -1950,7 +1950,7 @@ eal_legacy_hugepage_attach(void)
                if (ms_idx < 0) {
                        RTE_LOG(DEBUG, EAL, "%s(): Cannot find memseg idx\n",
                                __func__);
-                       goto fd_error;
+                       goto mmap_error;
                }
 
                /* store segment fd internally */
@@ -1963,18 +1963,15 @@ eal_legacy_hugepage_attach(void)
        close(fd_hugepage);
        return 0;
 
+mmap_error:
+       munmap(hp[i].final_va, hp[i].size);
 fd_error:
        close(fd);
 error:
-       /* map all segments into memory to make sure we get the addrs */
-       cur_seg = 0;
-       for (cur_seg = 0; cur_seg < i; cur_seg++) {
-               struct hugepage_file *hf = &hp[i];
-               size_t map_sz = hf->size;
-               void *map_addr = hf->final_va;
+       /* unwind mmap's done so far */
+       for (cur_seg = 0; cur_seg < i; cur_seg++)
+               munmap(hp[cur_seg].final_va, hp[cur_seg].size);
 
-               munmap(map_addr, map_sz);
-       }
        if (hp != NULL && hp != MAP_FAILED)
                munmap(hp, size);
        if (fd_hugepage >= 0)
-- 
2.20.1