regulator: event: Ensure atomicity for sequence number

Previously, the sequence number in the regulator event subsystem was
updated without atomic operations, potentially leading to race
conditions. This commit addresses the issue by making the sequence
number atomic.

Signed-off-by: Naresh Solanki <[email protected]>
Link: https://msgid.link/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>

diff --git a/drivers/regulator/event.c b/drivers/regulator/event.c
index 0ec58f306b3866bdf68648aeb7ce9613ce6bf1a7..ea3bd49544e88a532b5bcee0393f53c82431ff23 100644 (file)
--- a/drivers/regulator/event.c
+++ b/drivers/regulator/event.c
@@ -8,10 +8,11 @@
 #include <regulator/regulator.h>
 #include <net/netlink.h>
 #include <net/genetlink.h>
+#include <linux/atomic.h>
 
 #include "regnl.h"
 
-static unsigned int reg_event_seqnum;
+static atomic_t reg_event_seqnum = ATOMIC_INIT(0);
 
 static const struct genl_multicast_group reg_event_mcgrps[] = {
        { .name = REG_GENL_MCAST_GROUP_NAME, },
@@ -43,9 +44,8 @@ int reg_generate_netlink_event(const char *reg_name, u64 event)
                return -ENOMEM;
 
        /* add the genetlink message header */
-       msg_header = genlmsg_put(skb, 0, reg_event_seqnum++,
-                                &reg_event_genl_family, 0,
-                                REG_GENL_CMD_EVENT);
+       msg_header = genlmsg_put(skb, 0, atomic_inc_return(&reg_event_seqnum),
+                                &reg_event_genl_family, 0, REG_GENL_CMD_EVENT);
        if (!msg_header) {
                nlmsg_free(skb);
                return -ENOMEM;