From 9b9b6d8c7b10c069d36f85bd17f144011282cb58 Mon Sep 17 00:00:00 2001

From: Michal Sekletar <msekleta@redhat.com>

Date: Tue, 22 Jan 2019 14:29:50 +0100

Subject: [PATCH] process-util: don't use overly large buffer to store process

 command line

Allocate new string as a return value and free our "scratch pad"

buffer that is potentially much larger than needed (up to

_SC_ARG_MAX).

Fixes #11502

(cherry-picked from commit eb1ec489eef8a32918bbfc56a268c9d10464584d)

Related: #1664976

---

 src/basic/process-util.c | 18 ++++++++++++++----

 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/src/basic/process-util.c b/src/basic/process-util.c

index a20f1e3ccf..aa3eff779a 100644

--- a/src/basic/process-util.c

+++ b/src/basic/process-util.c

@@ -101,7 +101,8 @@ int get_process_comm(pid_t pid, char **ret) {

 int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char **line) {

         _cleanup_fclose_ FILE *f = NULL;

         bool space = false;

-        char *k, *ans = NULL;

+        char *k;

+        _cleanup_free_ char *ans = NULL;

         const char *p;

         int c;

@@ -142,7 +143,7 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *

                 if (!ans)

                         return -ENOMEM;

-                *line = ans;

+                *line = TAKE_PTR(ans);

                 return 0;

         } else {

@@ -207,7 +208,7 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *

                 _cleanup_free_ char *t = NULL;

                 int h;

-                free(ans);

+                ans = mfree(ans);

                 if (!comm_fallback)

                         return -ENOENT;

@@ -240,9 +241,18 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *

                         if (!ans)

                                 return -ENOMEM;

                 }

+

+                *line = TAKE_PTR(ans);

+                return 0;

         }

-        *line = ans;

+        k = realloc(ans, strlen(ans) + 1);

+        if (!k)

+                return -ENOMEM;

+

+        ans = NULL;

+        *line = k;

+

         return 0;

 }