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Remove the incorrect check for visited inodes #659

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Remove the incorrect check for visited inodes #659

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51f9c45
Add tests for valid symlinks followed twice
dkovba Apr 7, 2026
f3cecb5
Remove the incorrect check for visited inodes
dkovba Apr 7, 2026
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7 changes: 0 additions & 7 deletions Sources/ContainerizationEXT4/EXT4Reader+IO.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -281,7 +281,6 @@ extension EXT4.EXT4Reader {
var parentStack: [EXT4.InodeNumber] = [] // Track parent chain for proper ".." handling

var symlinkHops = 0
var visitedInodes = Set<EXT4.InodeNumber>()

// Process components one at a time to handle symlinks in the middle of paths
var componentIndex = 0
Expand Down Expand Up @@ -330,12 +329,6 @@ extension EXT4.EXT4Reader {
// Check if child is a symlink
let childInode = try getInode(number: child.1)
if childInode.mode.isLink() && followSymlinks {
// Check for symlink loop
if visitedInodes.contains(child.1) {
throw EXT4.PathIOError.symlinkLoop(FilePath(components.joined(separator: "/")).description)
}
visitedInodes.insert(child.1)

// Enforce max symlink depth
symlinkHops += 1
if symlinkHops > maxSymlinks {
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28 changes: 28 additions & 0 deletions Tests/ContainerizationEXT4Tests/TestEXT4Reader+IO.swift
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Expand Up @@ -499,6 +499,34 @@ struct EXT4PathIOTests {
}
}

@Test
func sameAbsoluteSymlinkFollowedTwice() throws {
let url = try buildFS { fmt in
try self.createDir(fmt, "/target")
try self.createFile(fmt, "/target/file.txt", "OK")
try self.createSymlink(fmt, "/symlink", "/target")
}
defer { try? FileManager.default.removeItem(at: url) }

let r = try openReader(url)
let data = try r.readFile(at: FilePath("/symlink/../symlink/file.txt"))
#expect(String(decoding: data, as: UTF8.self) == "OK")
}

@Test
func sameRelativeSymlinkFollowedTwice() throws {
let url = try buildFS { fmt in
try self.createDir(fmt, "/target")
try self.createFile(fmt, "/target/file.txt", "OK")
try self.createSymlink(fmt, "/symlink", "../target")
}
defer { try? FileManager.default.removeItem(at: url) }

let r = try openReader(url)
let data = try r.readFile(at: FilePath("/symlink/../symlink/file.txt"))
#expect(String(decoding: data, as: UTF8.self) == "OK")
}

@Test
func boundsCheckingForInvalidExtents() throws {
// This test verifies that the reader properly validates extent addresses
Expand Down
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