[PATCH] power: supply: qcom_battmgr: fix battery chemistry strncmp length
From: Tingguo Cheng
Date: Wed Aug 12 2026 - 03:53:13 EST
From: Tingguo Cheng <tingguoc@xxxxxxxxxxxxxxxx>
The battery_chemistry field is a 4-byte array without guaranteed null
termination. Using BATTMGR_CHEMISTRY_LEN (4) as the strncmp length for
3-character string literals implicitly requires chemistry[3] == '\0',
which may not hold. Use 3 instead to match only the significant bytes.
Signed-off-by: Tingguo Cheng <tingguo.cheng@xxxxxxxxxxxxxxxx>
---
drivers/power/supply/qcom_battmgr.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/power/supply/qcom_battmgr.c b/drivers/power/supply/qcom_battmgr.c
index 91cf39b0083a..7716eb9e1aff 100644
--- a/drivers/power/supply/qcom_battmgr.c
+++ b/drivers/power/supply/qcom_battmgr.c
@@ -1238,11 +1238,11 @@ static void qcom_battmgr_sc8280xp_strcpy(char *dest, const char *src)
static unsigned int qcom_battmgr_sc8280xp_parse_technology(const char *chemistry)
{
- if ((!strncmp(chemistry, "LIO", BATTMGR_CHEMISTRY_LEN)) ||
- (!strncmp(chemistry, "OOI", BATTMGR_CHEMISTRY_LEN)))
+ if ((!strncmp(chemistry, "LIO", 3)) ||
+ (!strncmp(chemistry, "OOI", 3)))
return POWER_SUPPLY_TECHNOLOGY_LION;
- if (!strncmp(chemistry, "LIP", BATTMGR_CHEMISTRY_LEN) ||
- !strncmp(chemistry, "LiP", BATTMGR_CHEMISTRY_LEN))
+ if (!strncmp(chemistry, "LIP", 3) ||
+ !strncmp(chemistry, "LiP", 3))
return POWER_SUPPLY_TECHNOLOGY_LIPO;
pr_err("Unknown battery technology '%s'\n", chemistry);
---
base-commit: 8ca3d2492e247e36fa9a4350fba2010ea5eec6f6
change-id: 20260812-fix-qcom-batt-chemistry-strn-6434c631ecb5
Best regards,
--
Tingguo Cheng <tingguo.cheng@xxxxxxxxxxxxxxxx>