Add staticcheck and staticstyle analyzers.

This change also adds support to go_stateify for detecting an appropriate
receiver name, avoiding a large number of false positives.

PiperOrigin-RevId: 335994587

4 files changed, 22 insertions, 29 deletions

diff --git a/pkg/sentry/fs/fsutil/inode_cached.go b/pkg/sentry/fs/fsutil/inode_cached.go
index 9eb6f522e..85a23432b 100644
--- a/pkg/sentry/fs/fsutil/inode_cached.go
+++ b/pkg/sentry/fs/fsutil/inode_cached.go
@@ -22,7 +22,6 @@ import (
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/pkg/safemem"
 	"gvisor.dev/gvisor/pkg/sentry/fs"
-	"gvisor.dev/gvisor/pkg/sentry/kernel/time"
 	ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time"
 	"gvisor.dev/gvisor/pkg/sentry/memmap"
 	"gvisor.dev/gvisor/pkg/sentry/pgalloc"
@@ -444,7 +443,7 @@ func (c *CachingInodeOperations) TouchAccessTime(ctx context.Context, inode *fs.
 // time.
 //
 // Preconditions: c.attrMu is locked for writing.
-func (c *CachingInodeOperations) touchAccessTimeLocked(now time.Time) {
+func (c *CachingInodeOperations) touchAccessTimeLocked(now ktime.Time) {
 	c.attr.AccessTime = now
 	c.dirtyAttr.AccessTime = true
 }
@@ -461,7 +460,7 @@ func (c *CachingInodeOperations) TouchModificationAndStatusChangeTime(ctx contex
 // and status change times in-place to the current time.
 //
 // Preconditions: c.attrMu is locked for writing.
-func (c *CachingInodeOperations) touchModificationAndStatusChangeTimeLocked(now time.Time) {
+func (c *CachingInodeOperations) touchModificationAndStatusChangeTimeLocked(now ktime.Time) {
 	c.attr.ModificationTime = now
 	c.dirtyAttr.ModificationTime = true
 	c.attr.StatusChangeTime = now
@@ -480,7 +479,7 @@ func (c *CachingInodeOperations) TouchStatusChangeTime(ctx context.Context) {
 // in-place to the current time.
 //
 // Preconditions: c.attrMu is locked for writing.
-func (c *CachingInodeOperations) touchStatusChangeTimeLocked(now time.Time) {
+func (c *CachingInodeOperations) touchStatusChangeTimeLocked(now ktime.Time) {
 	c.attr.StatusChangeTime = now
 	c.dirtyAttr.StatusChangeTime = true
 }
@@ -672,9 +671,6 @@ func (rw *inodeReadWriter) ReadToBlocks(dsts safemem.BlockSeq) (uint64, error) {
 				// Continue.
 				seg, gap = gap.NextSegment(), FileRangeGapIterator{}
 			}
-
-		default:
-			break
 		}
 	}
 	unlock()
@@ -768,9 +764,6 @@ func (rw *inodeReadWriter) WriteFromBlocks(srcs safemem.BlockSeq) (uint64, error
 
 			// Continue.
 			seg, gap = gap.NextSegment(), FileRangeGapIterator{}
-
-		default:
-			break
 		}
 	}
 	rw.maybeGrowFile()
diff --git a/pkg/sentry/memmap/memmap.go b/pkg/sentry/memmap/memmap.go
index a44fa2b95..7fd77925f 100644
--- a/pkg/sentry/memmap/memmap.go
+++ b/pkg/sentry/memmap/memmap.go
@@ -127,7 +127,7 @@ func (t Translation) FileRange() FileRange {
 // Preconditions: Same as Mappable.Translate.
 func CheckTranslateResult(required, optional MappableRange, at usermem.AccessType, ts []Translation, terr error) error {
 	// Verify that the inputs to Mappable.Translate were valid.
-	if !required.WellFormed() || required.Length() <= 0 {
+	if !required.WellFormed() || required.Length() == 0 {
 		panic(fmt.Sprintf("invalid required range: %v", required))
 	}
 	if !usermem.Addr(required.Start).IsPageAligned() || !usermem.Addr(required.End).IsPageAligned() {
@@ -145,7 +145,7 @@ func CheckTranslateResult(required, optional MappableRange, at usermem.AccessTyp
 		return fmt.Errorf("first Translation %+v does not cover start of required range %v", ts[0], required)
 	}
 	for i, t := range ts {
-		if !t.Source.WellFormed() || t.Source.Length() <= 0 {
+		if !t.Source.WellFormed() || t.Source.Length() == 0 {
 			return fmt.Errorf("Translation %+v has invalid Source", t)
 		}
 		if !usermem.Addr(t.Source.Start).IsPageAligned() || !usermem.Addr(t.Source.End).IsPageAligned() {
diff --git a/pkg/sentry/mm/pma.go b/pkg/sentry/mm/pma.go
index 30facebf7..7e5f7de64 100644
--- a/pkg/sentry/mm/pma.go
+++ b/pkg/sentry/mm/pma.go
@@ -36,7 +36,7 @@ import (
 // * ar.Length() != 0.
 func (mm *MemoryManager) existingPMAsLocked(ar usermem.AddrRange, at usermem.AccessType, ignorePermissions bool, needInternalMappings bool) pmaIterator {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 {
+		if !ar.WellFormed() || ar.Length() == 0 {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 	}
@@ -100,7 +100,7 @@ func (mm *MemoryManager) existingVecPMAsLocked(ars usermem.AddrRangeSeq, at user
 //   (i.e. permission checks must have been performed against vmas).
 func (mm *MemoryManager) getPMAsLocked(ctx context.Context, vseg vmaIterator, ar usermem.AddrRange, at usermem.AccessType) (pmaIterator, pmaGapIterator, error) {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 {
+		if !ar.WellFormed() || ar.Length() == 0 {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 		if !vseg.Ok() {
@@ -193,7 +193,7 @@ func (mm *MemoryManager) getVecPMAsLocked(ctx context.Context, ars usermem.AddrR
 // getVecPMAsLocked; other clients should call one of those instead.
 func (mm *MemoryManager) getPMAsInternalLocked(ctx context.Context, vseg vmaIterator, ar usermem.AddrRange, at usermem.AccessType) (pmaIterator, pmaGapIterator, error) {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 || !ar.IsPageAligned() {
+		if !ar.WellFormed() || ar.Length() == 0 || !ar.IsPageAligned() {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 		if !vseg.Ok() {
@@ -223,7 +223,7 @@ func (mm *MemoryManager) getPMAsInternalLocked(ctx context.Context, vseg vmaIter
 				// Need a pma here.
 				optAR := vseg.Range().Intersect(pgap.Range())
 				if checkInvariants {
-					if optAR.Length() <= 0 {
+					if optAR.Length() == 0 {
 						panic(fmt.Sprintf("vseg %v and pgap %v do not overlap", vseg, pgap))
 					}
 				}
@@ -560,7 +560,7 @@ func (mm *MemoryManager) isPMACopyOnWriteLocked(vseg vmaIterator, pseg pmaIterat
 // Invalidate implements memmap.MappingSpace.Invalidate.
 func (mm *MemoryManager) Invalidate(ar usermem.AddrRange, opts memmap.InvalidateOpts) {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 || !ar.IsPageAligned() {
+		if !ar.WellFormed() || ar.Length() == 0 || !ar.IsPageAligned() {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 	}
@@ -583,7 +583,7 @@ func (mm *MemoryManager) Invalidate(ar usermem.AddrRange, opts memmap.Invalidate
 // * ar must be page-aligned.
 func (mm *MemoryManager) invalidateLocked(ar usermem.AddrRange, invalidatePrivate, invalidateShared bool) {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 || !ar.IsPageAligned() {
+		if !ar.WellFormed() || ar.Length() == 0 || !ar.IsPageAligned() {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 	}
@@ -629,7 +629,7 @@ func (mm *MemoryManager) invalidateLocked(ar usermem.AddrRange, invalidatePrivat
 // * ar must be page-aligned.
 func (mm *MemoryManager) Pin(ctx context.Context, ar usermem.AddrRange, at usermem.AccessType, ignorePermissions bool) ([]PinnedRange, error) {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 || !ar.IsPageAligned() {
+		if !ar.WellFormed() || ar.Length() == 0 || !ar.IsPageAligned() {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 	}
@@ -715,10 +715,10 @@ func Unpin(prs []PinnedRange) {
 // * oldAR and newAR must be page-aligned.
 func (mm *MemoryManager) movePMAsLocked(oldAR, newAR usermem.AddrRange) {
 	if checkInvariants {
-		if !oldAR.WellFormed() || oldAR.Length() <= 0 || !oldAR.IsPageAligned() {
+		if !oldAR.WellFormed() || oldAR.Length() == 0 || !oldAR.IsPageAligned() {
 			panic(fmt.Sprintf("invalid oldAR: %v", oldAR))
 		}
-		if !newAR.WellFormed() || newAR.Length() <= 0 || !newAR.IsPageAligned() {
+		if !newAR.WellFormed() || newAR.Length() == 0 || !newAR.IsPageAligned() {
 			panic(fmt.Sprintf("invalid newAR: %v", newAR))
 		}
 		if oldAR.Length() > newAR.Length() {
@@ -778,7 +778,7 @@ func (mm *MemoryManager) movePMAsLocked(oldAR, newAR usermem.AddrRange) {
 // into mm.pmas.
 func (mm *MemoryManager) getPMAInternalMappingsLocked(pseg pmaIterator, ar usermem.AddrRange) (pmaGapIterator, error) {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 {
+		if !ar.WellFormed() || ar.Length() == 0 {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 		if !pseg.Range().Contains(ar.Start) {
@@ -831,7 +831,7 @@ func (mm *MemoryManager) getVecPMAInternalMappingsLocked(ars usermem.AddrRangeSe
 // * pseg.Range().Contains(ar.Start).
 func (mm *MemoryManager) internalMappingsLocked(pseg pmaIterator, ar usermem.AddrRange) safemem.BlockSeq {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 {
+		if !ar.WellFormed() || ar.Length() == 0 {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 		if !pseg.Range().Contains(ar.Start) {
@@ -1050,7 +1050,7 @@ func (pseg pmaIterator) fileRangeOf(ar usermem.AddrRange) memmap.FileRange {
 		if !pseg.Ok() {
 			panic("terminal pma iterator")
 		}
-		if !ar.WellFormed() || ar.Length() <= 0 {
+		if !ar.WellFormed() || ar.Length() == 0 {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 		if !pseg.Range().IsSupersetOf(ar) {
diff --git a/pkg/sentry/mm/vma.go b/pkg/sentry/mm/vma.go
index f769d8294..b8df72813 100644
--- a/pkg/sentry/mm/vma.go
+++ b/pkg/sentry/mm/vma.go
@@ -266,7 +266,7 @@ func (mm *MemoryManager) mlockedBytesRangeLocked(ar usermem.AddrRange) uint64 {
 // * ar.Length() != 0.
 func (mm *MemoryManager) getVMAsLocked(ctx context.Context, ar usermem.AddrRange, at usermem.AccessType, ignorePermissions bool) (vmaIterator, vmaGapIterator, error) {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 {
+		if !ar.WellFormed() || ar.Length() == 0 {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 	}
@@ -350,7 +350,7 @@ const guardBytes = 256 * usermem.PageSize
 // * ar must be page-aligned.
 func (mm *MemoryManager) unmapLocked(ctx context.Context, ar usermem.AddrRange) vmaGapIterator {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 || !ar.IsPageAligned() {
+		if !ar.WellFormed() || ar.Length() == 0 || !ar.IsPageAligned() {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 	}
@@ -371,7 +371,7 @@ func (mm *MemoryManager) unmapLocked(ctx context.Context, ar usermem.AddrRange)
 // * ar must be page-aligned.
 func (mm *MemoryManager) removeVMAsLocked(ctx context.Context, ar usermem.AddrRange) vmaGapIterator {
 	if checkInvariants {
-		if !ar.WellFormed() || ar.Length() <= 0 || !ar.IsPageAligned() {
+		if !ar.WellFormed() || ar.Length() == 0 || !ar.IsPageAligned() {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 	}
@@ -511,7 +511,7 @@ func (vseg vmaIterator) mappableRangeOf(ar usermem.AddrRange) memmap.MappableRan
 		if vseg.ValuePtr().mappable == nil {
 			panic("MappableRange is meaningless for anonymous vma")
 		}
-		if !ar.WellFormed() || ar.Length() <= 0 {
+		if !ar.WellFormed() || ar.Length() == 0 {
 			panic(fmt.Sprintf("invalid ar: %v", ar))
 		}
 		if !vseg.Range().IsSupersetOf(ar) {
@@ -536,7 +536,7 @@ func (vseg vmaIterator) addrRangeOf(mr memmap.MappableRange) usermem.AddrRange {
 		if vseg.ValuePtr().mappable == nil {
 			panic("MappableRange is meaningless for anonymous vma")
 		}
-		if !mr.WellFormed() || mr.Length() <= 0 {
+		if !mr.WellFormed() || mr.Length() == 0 {
 			panic(fmt.Sprintf("invalid mr: %v", mr))
 		}
 		if !vseg.mappableRange().IsSupersetOf(mr) {