From e06664f379eab0b3f80c504c6656f805bba30e69 Mon Sep 17 00:00:00 2001
From: David Vernet <void@manifault.com>
Date: Thu, 13 Jan 2022 12:57:15 -0800
Subject: [PATCH] kpatch-build: Add missing allocation failure checks

In kpatch-build, there are a number of places where a dynamic allocation
is performed, but the allocation is not checked for a failure. The
common pattern in kpatch-build is to check whether the returned pointer
is NULL, and if so, invoke the ERROR() macro to print a message and
abort the program.

kpatch_create_mcount_sections(), CORRELATE_ELEMENT(), and
create_klp_arch_sections() all had dynamic allocations without failure
checks. This diff adjusts those callsites to properly check for a failed
allocation, and ERROR() accordingly.

Signed-off-by: David Vernet <void@manifault.com>
---
 kpatch-build/create-diff-object.c | 4 ++++
 kpatch-build/create-klp-module.c  | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/kpatch-build/create-diff-object.c b/kpatch-build/create-diff-object.c
index 442d8f8..01e5d63 100644
--- a/kpatch-build/create-diff-object.c
+++ b/kpatch-build/create-diff-object.c
@@ -979,6 +979,8 @@ do {								\
 		log_debug("renaming %s %s to %s\n",		\
 			  kindstr, e2->name, e1->name);		\
 		e2->name = strdup(e1->name);			\
+		if (!e2->name)				        \
+			ERROR("strdup");			\
 	}							\
 } while (0)
 
@@ -3688,6 +3690,8 @@ static void kpatch_create_mcount_sections(struct kpatch_elf *kelf)
 
 			/* Make a writable copy of the text section data */
 			newdata = malloc(sym->sec->data->d_size);
+			if (!newdata)
+				ERROR("malloc");
 			memcpy(newdata, sym->sec->data->d_buf, sym->sec->data->d_size);
 			sym->sec->data->d_buf = newdata;
 			insn = newdata;
diff --git a/kpatch-build/create-klp-module.c b/kpatch-build/create-klp-module.c
index 547e587..8ceb8f3 100644
--- a/kpatch-build/create-klp-module.c
+++ b/kpatch-build/create-klp-module.c
@@ -343,6 +343,8 @@ static void create_klp_arch_sections(struct kpatch_elf *kelf, char *strings)
 
 		new_size = old_size + base->data->d_size;
 		sec->data->d_buf = realloc(sec->data->d_buf, new_size);
+		if (!sec->data->d_buf)
+			ERROR("realloc");
 		sec->data->d_size = new_size;
 		sec->sh.sh_size = sec->data->d_size;
 		memcpy(sec->data->d_buf + old_size,
-- 
2.27.0