+ tools-mm-page_owner_sort-free-per-record-allocations.patch added to mm-new branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: tools/mm/page_owner_sort: free per-record allocations
has been added to the -mm mm-new branch.  Its filename is
     tools-mm-page_owner_sort-free-per-record-allocations.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/tools-mm-page_owner_sort-free-per-record-allocations.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

If a few days of testing in mm-new is successful, the patch will me moved
into mm.git's mm-unstable branch, which is included in linux-next

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------------------------------------------------------
From: Yichong Chen <chenyichong@uniontech.com>
Subject: tools/mm/page_owner_sort: free per-record allocations
Date: Mon, 29 Jun 2026 09:43:15 +0800

add_list() allocates comm and txt for each page owner record, but the
cleanup path only frees the outer list array.  This leaks both buffers for
every retained record.

Free partial allocations in add_list(), discarded records during culling,
and retained records on exit.

Link: https://lore.kernel.org/20260629014316.130307-3-chenyichong@uniontech.com
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Reviewed-by: Vishal Moola <vishal.moola@gmail.com>
Cc: Ye Liu <ye.liu@linux.dev>
Cc: Zhen Ni <zhen.ni@easystack.cn>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/mm/page_owner_sort.c |   20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

--- a/tools/mm/page_owner_sort.c~tools-mm-page_owner_sort-free-per-record-allocations
+++ a/tools/mm/page_owner_sort.c
@@ -396,6 +396,12 @@ static char *get_comm(char *buf)
 	return comm_str;
 }
 
+static void free_block_list(struct block_list *block)
+{
+	free(block->comm);
+	free(block->txt);
+}
+
 static int get_arg_type(const char *arg)
 {
 	if (!strcmp(arg, "pid") || !strcmp(arg, "p"))
@@ -502,9 +508,14 @@ static bool add_list(char *buf, int len,
 	list[list_size].pid = get_pid(buf);
 	list[list_size].tgid = get_tgid(buf);
 	list[list_size].comm = get_comm(buf);
-	list[list_size].txt = malloc(len+1);
+	if (!list[list_size].comm) {
+		fprintf(stderr, "Out of memory\n");
+		return false;
+	}
+	list[list_size].txt = malloc(len + 1);
 	if (!list[list_size].txt) {
 		fprintf(stderr, "Out of memory\n");
+		free(list[list_size].comm);
 		return false;
 	}
 	memcpy(list[list_size].txt, buf, len);
@@ -863,8 +874,10 @@ int main(int argc, char **argv)
 		} else {
 			list[count-1].num += list[i].num;
 			list[count-1].page_num += list[i].page_num;
+			free_block_list(&list[i]);
 		}
 	}
+	list_size = count;
 
 	qsort(list, count, sizeof(list[0]), compare_sort_condition);
 
@@ -898,8 +911,11 @@ out_free:
 		free(ext_buf);
 	if (buf)
 		free(buf);
-	if (list)
+	if (list) {
+		for (i = 0; i < list_size; i++)
+			free_block_list(&list[i]);
 		free(list);
+	}
 out_ts:
 	regfree(&ts_nsec_pattern);
 out_comm:
_

Patches currently in -mm which might be from chenyichong@uniontech.com are

tools-mm-page_owner_sort-return-explicit-filter-results.patch
tools-mm-page_owner_sort-free-per-record-allocations.patch
tools-mm-page_owner_sort-bound-pattern-output-copies.patch