[PATCH 2/5] kallsyms: replace sprintf with scnprintf

From: Maninder Singh <maninder1.s@samsung.com>
To: keescook@chromium.org, pmladek@suse.com, bcain@quicinc.com,
	mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org,
	hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com,
	borntraeger@linux.ibm.com, svens@linux.ibm.com,
	satishkh@cisco.com, sebaddel@cisco.com, kartilak@cisco.com,
	jejb@linux.ibm.com, martin.petersen@oracle.com,
	mcgrof@kernel.org, jason.wessel@windriver.com,
	daniel.thompson@linaro.org, dianders@chromium.org,
	naveen.n.rao@linux.ibm.com, anil.s.keshavamurthy@intel.com,
	davem@davemloft.net, mhiramat@kernel.org, peterz@infradead.org,
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Cc: linux-hexagon@vger.kernel.org, linux-kernel@vger.kernel.org,
	linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
	linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-modules@vger.kernel.org,
	kgdb-bugreport@lists.sourceforge.net, v.narang@samsung.com,
	onkarnath.1@samsung.com, Maninder Singh <maninder1.s@samsung.com>
Subject: [PATCH 2/5] kallsyms: replace sprintf with scnprintf
Date: Fri, 20 May 2022 14:06:58 +0530	[thread overview]
Message-ID: <20220520083701.2610975-3-maninder1.s@samsung.com> (raw)
In-Reply-To: <20220520083701.2610975-1-maninder1.s@samsung.com>

replace sprintf API with scnprintf which prevents buffer overflow.

Co-developed-by: Onkarnath <onkarnath.1@samsung.com>
Signed-off-by: Onkarnath <onkarnath.1@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
---
 kernel/kallsyms.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index f354378e241f..9e4316fe0ba1 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -472,28 +472,29 @@ static int __sprint_symbol(char *buffer, size_t buf_size, unsigned long address,
 	name = kallsyms_lookup_buildid(address, &size, &offset, &modname, &buildid,
 				       buffer);
 	if (!name)
-		return sprintf(buffer, "0x%lx", address - symbol_offset);
+		return scnprintf(buffer, buf_size, "0x%lx", address - symbol_offset);
 
 	if (name != buffer)
-		strcpy(buffer, name);
+		strncpy(buffer, name, buf_size);
+
 	len = strlen(buffer);
 	offset -= symbol_offset;
 
 	if (add_offset)
-		len += sprintf(buffer + len, "+%#lx/%#lx", offset, size);
+		len += scnprintf(buffer + len, buf_size - len, "+%#lx/%#lx", offset, size);
 
 	if (modname) {
-		len += sprintf(buffer + len, " [%s", modname);
+		len += scnprintf(buffer + len, buf_size - len, " [%s", modname);
 #if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
 		if (add_buildid && buildid) {
 			/* build ID should match length of sprintf */
 #if IS_ENABLED(CONFIG_MODULES)
 			static_assert(sizeof(typeof_member(struct module, build_id)) == 20);
 #endif
-			len += sprintf(buffer + len, " %20phN", buildid);
+			len += scnprintf(buffer + len, buf_size - len, " %20phN", buildid);
 		}
 #endif
-		len += sprintf(buffer + len, "]");
+		len += scnprintf(buffer + len, buf_size - len, "]");
 	}
 
 	return len;
-- 
2.17.1

