From: Arnaud Fontaine <arnaud.fontaine@airbus.com>
Date: Tue, 2 Apr 2024 08:49:34 +0000 (+0200)
Subject: tree-wide: replace multiply_overflow with check_mul_overflow
X-Git-Tag: v6.0.0~6^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ad8f554458d1e93bd5dbde7ed650cb24a5401ce3;p=thirdparty%2Flxc.git

tree-wide: replace multiply_overflow with check_mul_overflow

Remove redundant multiply_overflow helper and use check_mul_overflow.

This also fixes a bug with incorrect handling for negative offset values.

Link: #4374

Signed-off-by: Arnaud Fontaine <arnaud.fontaine@airbus.com>
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
---

diff --git a/src/lxc/confile.c b/src/lxc/confile.c
index bf0f10008..defb5ed96 100644
--- a/src/lxc/confile.c
+++ b/src/lxc/confile.c
@@ -2963,18 +2963,18 @@ static int set_config_time_offset_boot(const char *key, const char *value,
 
 	unit = lxc_trim_whitespace_in_place(buf);
 	if (strequal(unit, "h")) {
-		if (!multiply_overflow(offset, 3600, &lxc_conf->timens.s_boot))
+		if (check_mul_overflow(offset, (typeof(offset))3600, &lxc_conf->timens.s_boot))
 			return ret_errno(EOVERFLOW);
 	} else if (strequal(unit, "m")) {
-		if (!multiply_overflow(offset, 60, &lxc_conf->timens.s_boot))
+		if (check_mul_overflow(offset, (typeof(offset))60, &lxc_conf->timens.s_boot))
 			return ret_errno(EOVERFLOW);
 	} else if (strequal(unit, "s")) {
 		lxc_conf->timens.s_boot = offset;
 	} else if (strequal(unit, "ms")) {
-		if (!multiply_overflow(offset, 1000000, &lxc_conf->timens.ns_boot))
+		if (check_mul_overflow(offset, (typeof(offset))1000000, &lxc_conf->timens.ns_boot))
 			return ret_errno(EOVERFLOW);
 	} else if (strequal(unit, "us")) {
-		if (!multiply_overflow(offset, 1000, &lxc_conf->timens.ns_boot))
+		if (check_mul_overflow(offset, (typeof(offset))1000, &lxc_conf->timens.ns_boot))
 			return ret_errno(EOVERFLOW);
 	} else if (strequal(unit, "ns")) {
 		lxc_conf->timens.ns_boot = offset;
@@ -3002,18 +3002,18 @@ static int set_config_time_offset_monotonic(const char *key, const char *value,
 
 	unit = lxc_trim_whitespace_in_place(buf);
 	if (strequal(unit, "h")) {
-		if (!multiply_overflow(offset, 3600, &lxc_conf->timens.s_monotonic))
+		if (check_mul_overflow(offset, (typeof(offset))3600, &lxc_conf->timens.s_monotonic))
 			return ret_errno(EOVERFLOW);
 	} else if (strequal(unit, "m")) {
-		if (!multiply_overflow(offset, 60, &lxc_conf->timens.s_monotonic))
+		if (check_mul_overflow(offset, (typeof(offset))60, &lxc_conf->timens.s_monotonic))
 			return ret_errno(EOVERFLOW);
 	} else if (strequal(unit, "s")) {
 		lxc_conf->timens.s_monotonic = offset;
 	} else if (strequal(unit, "ms")) {
-		if (!multiply_overflow(offset, 1000000, &lxc_conf->timens.ns_monotonic))
+		if (check_mul_overflow(offset, (typeof(offset))1000000, &lxc_conf->timens.ns_monotonic))
 			return ret_errno(EOVERFLOW);
 	} else if (strequal(unit, "us")) {
-		if (!multiply_overflow(offset, 1000, &lxc_conf->timens.ns_monotonic))
+		if (check_mul_overflow(offset, (typeof(offset))1000, &lxc_conf->timens.ns_monotonic))
 			return ret_errno(EOVERFLOW);
 	} else if (strequal(unit, "ns")) {
 		lxc_conf->timens.ns_monotonic = offset;
diff --git a/src/lxc/utils.c b/src/lxc/utils.c
index 616544dd4..0b14c05ad 100644
--- a/src/lxc/utils.c
+++ b/src/lxc/utils.c
@@ -2071,18 +2071,6 @@ int fix_stdio_permissions(uid_t uid)
 	return fret;
 }
 
-bool multiply_overflow(int64_t base, uint64_t mult, int64_t *res)
-{
-	if (base > 0 && base > (int64_t)(INT64_MAX / mult))
-		return false;
-
-	if (base < 0 && base < (int64_t)(INT64_MIN / mult))
-		return false;
-
-	*res = (int64_t)(base * mult);
-	return true;
-}
-
 int print_r(int fd, const char *path)
 {
 	__do_close int dfd = -EBADF, dfd_dup = -EBADF;
diff --git a/src/lxc/utils.h b/src/lxc/utils.h
index 4040f9f1e..956ea2a5e 100644
--- a/src/lxc/utils.h
+++ b/src/lxc/utils.h
@@ -240,8 +240,6 @@ static inline bool gid_valid(gid_t gid)
 	return gid != LXC_INVALID_GID;
 }
 
-__hidden extern bool multiply_overflow(int64_t base, uint64_t mult, int64_t *res);
-
 __hidden extern int safe_mount_beneath(const char *beneath, const char *src, const char *dst,
 				       const char *fstype, unsigned int flags, const void *data);
 __hidden extern int safe_mount_beneath_at(int beneat_fd, const char *src, const char *dst,