From dbfc622345f95e09ce36cbecf70715b7adcad661 Mon Sep 17 00:00:00 2001 From: Richard Yao Date: Sat, 11 Mar 2023 13:39:24 -0500 Subject: [PATCH] nvpair: Use flexible array member for nvpair name strings Coverity reported possible out-of-bounds reads from doing `((char *)(nvp) + sizeof (nvpair_t))` to get the nvpair name string. These were initially marked as false positives, but since we are now using C99 flexible array members elsewhere, we could use them here too as cleanup to make the code easier to understand. Reviewed-by: Tino Reichardt Reviewed-by: Brian Behlendorf Signed-off-by: Richard Yao Reported-by: Coverity (CID-977165) Reported-by: Coverity (CID-1524109) Reported-by: Coverity (CID-1524642) Closes #14612 --- include/sys/nvpair.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/sys/nvpair.h b/include/sys/nvpair.h index 33eda9be10..2dbd9e3eaf 100644 --- a/include/sys/nvpair.h +++ b/include/sys/nvpair.h @@ -76,7 +76,7 @@ typedef struct nvpair { int16_t nvp_reserve; /* not used */ int32_t nvp_value_elem; /* number of elements for array types */ data_type_t nvp_type; /* type of value */ - /* name string */ + char nvp_name[]; /* name string */ /* aligned ptr array for string arrays */ /* aligned array of data for value */ } nvpair_t; @@ -109,7 +109,7 @@ typedef struct nvlist { #define NV_ALIGN4(x) (((x) + 3) & ~3) #define NVP_SIZE(nvp) ((nvp)->nvp_size) -#define NVP_NAME(nvp) ((char *)(nvp) + sizeof (nvpair_t)) +#define NVP_NAME(nvp) ((nvp)->nvp_name) #define NVP_TYPE(nvp) ((nvp)->nvp_type) #define NVP_NELEM(nvp) ((nvp)->nvp_value_elem) #define NVP_VALUE(nvp) ((char *)(nvp) + NV_ALIGN(sizeof (nvpair_t) \