fix: optimize packages upload memory (#39366)

Bound the memory used when parsing uploaded packages, so instances with
low memory limits survive non-standard packages.

1. Metadata files are read through a size-limited reader, archives
themselves stay unbounded so large payloads keep working
2. zstd decoding caps the window at 128 MiB, the zstd CLI default
3. RPM headers go through a first-party reader with rpmlib's size and
array count limits that allocates only what the upload contains, until
https://github.com/sassoftware/go-rpmutils/pull/44 is released. Signing
still verifies the payload digest, and its signature header matches
rpmsign's byte for byte
4. Swift and NuGet read the zip entry they size-checked, a duplicate
name could stand in for it before
5. Terraform states check `LIMIT_SIZE_TERRAFORM_STATE` before parsing,
NuGet symbol PDBs share a 256 MiB budget
6. Oversized container configs are rejected instead of stored without
metadata, invalid Vagrant boxes answer 400 instead of 500

Signed-off-by: techknowlogick <git@tklk.dev>
Co-authored-by: techknowlogick <git@tklk.dev>
Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: techknowlogick <techknowlogick@gitea.com>

modules/packages/terraform/lock.go

@@ -12,12 +12,17 @@ import (
 	"gitea.dev/models/db"
 	packages_model "gitea.dev/models/packages"
 	"gitea.dev/modules/json"
+	"gitea.dev/modules/packages"
 	"gitea.dev/modules/util"
 
 	"xorm.io/builder"
 )
 
-const LockFile = "terraform.lock"
+const (
+	LockFile = "terraform.lock"
+
+	maxLockInfoSize = 64 * 1024
+)
 
 // LockInfo is the metadata for a terraform lock.
 type LockInfo struct {
@@ -36,7 +41,7 @@ func (l *LockInfo) IsLocked() bool {
 
 func ParseLockInfo(r io.Reader) (*LockInfo, error) {
 	var lock LockInfo
-	err := json.NewDecoder(r).Decode(&lock)
+	err := json.NewDecoder(packages.NewLimitedReader(r, maxLockInfoSize)).Decode(&lock)
 	if err != nil {
 		return nil, err
 	}