pmap: fix printing bug associated with the '-x' option

Ever since its introduction, the 'x' (extended format)
option has employed strncmp to parse those smaps keys.

Such an approach worked well as long as those prefixes
were guaranteed to be unique. But, with the 4.3 kernel
a new 'SwapPss' field was added to those within smaps.

That triggered a 2nd match for the 'Swap' logic which,
in turn, resulted in a duplicate output line of zeros.

So this patch just trades strncmp for strcmp, avoiding
potential future problems when /proc/$$/smaps evolves.

Reference(s):
. recent bug report
https://bugzilla.redhat.com/show_bug.cgi?id=1374061
. linux 4.3 kernel introduces SwapPss
commit 8334b96221ff0dcbde4873d31eb4d84774ed8ed4
. original pmap -x option introduction
commit 380cc1e9082d662d09dd80fcbb73de9dc98b3ea1

Signed-off-by: Jim Warner <james.warner@comcast.net>

diff --git a/NEWS b/NEWS
index dcb92ff048192d275989afd59d7f33dd37ae4a4d..c38c904abe833d46ff165268b83a7d189531edee 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -3,6 +3,7 @@ procps-ng-NEXT
   * watch: define HOST_NAME_MAX where not defined          Debian #830734
   * library: dont use vm_min_free on non Linux             Debian #831396
   * library: dont use SIGPWR on FreeBSD                    Debian #832148
+  * pmap: fix duplicate output line under '-x' option      Redhat #1374061
 
 procps-ng-3.3.12
 ----------------

diff --git a/pmap.c b/pmap.c
index 61aca2c355ce2e6c9f64a7d6ef41438ce1d56895..41116edcb9ca6aca0f3c3cd90e2725fabd848d48 100644 (file)
--- a/pmap.c
+++ b/pmap.c
@@ -597,25 +597,23 @@ static int one_proc(proc_t * p)
                /* hex values are lower case or numeric, keys are upper */
                if (mapbuf[0] >= 'A' && mapbuf[0] <= 'Z') {
                        /* Its a key */
-                       if (sscanf
-                           (mapbuf, "%20[^:]: %llu", smap_key,
-                            &smap_value) == 2) {
-                               if (strncmp("Rss", smap_key, 3) == 0) {
+                       if (sscanf(mapbuf, "%20[^:]: %llu", smap_key, &smap_value) == 2) {
+                               if (strcmp("Rss", smap_key) == 0) {
                                        rss = smap_value;
                                        total_rss += smap_value;
                                        continue;
                                }
-                               if (strncmp("Shared_Dirty", smap_key, 12) == 0) {
+                               if (strcmp("Shared_Dirty", smap_key) == 0) {
                                        shared_dirty = smap_value;
                                        total_shared_dirty += smap_value;
                                        continue;
                                }
-                               if (strncmp("Private_Dirty", smap_key, 13) == 0) {
+                               if (strcmp("Private_Dirty", smap_key) == 0) {
                                        private_dirty = smap_value;
                                        total_private_dirty += smap_value;
                                        continue;
                                }
-                               if (strncmp("Swap", smap_key, 4) == 0) {
+                               if (strcmp("Swap", smap_key) == 0) {
                                        /*doesn't matter as long as last */
                                        printf("%0*" KLF "x %*lu %*llu %*llu %*s %s\n",
                                               maxw1, start,