snprintf() returns the number of characters that *would* have been written, which can overestimate how much you actually wrote to the buffer in case of truncation. That leads to 'data += this' advancing the pointer past the end of the buffer and size going negative.
Switching to scnprintf() prevents potential buffer overflows and ensures consistent behavior when building the output string. Signed-off-by: Seyediman Seyedarab <imande...@gmail.com> --- drivers/gpu/drm/nouveau/nvkm/core/enum.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/nouveau/nvkm/core/enum.c b/drivers/gpu/drm/nouveau/nvkm/core/enum.c index b9581feb24cc..a23b40b27b81 100644 --- a/drivers/gpu/drm/nouveau/nvkm/core/enum.c +++ b/drivers/gpu/drm/nouveau/nvkm/core/enum.c @@ -44,7 +44,7 @@ nvkm_snprintbf(char *data, int size, const struct nvkm_bitfield *bf, u32 value) bool space = false; while (size >= 1 && bf->name) { if (value & bf->mask) { - int this = snprintf(data, size, "%s%s", + int this = scnprintf(data, size, "%s%s", space ? " " : "", bf->name); size -= this; data += this; -- 2.50.1