Skip to content

Swift: Query for escaping parameters of unsafe closures #13706

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
wants to merge 9 commits into
base: main
Choose a base branch
from
Draft

Swift: Query for escaping parameters of unsafe closures #13706

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
9 commits
Select commit Hold shift + click to select a range
1cac879
Initial test for pointer escaping withUnsafeBytes
rdmarsh2 Jul 10, 2023
83a787e
Swift: initial query for unsafe closure arg escape
rdmarsh2 Jul 10, 2023
f27522d
Swift: relocate UnsafePointerEscapesClosure
rdmarsh2 Jul 11, 2023
db18915
Swift: add more funcs to unsafe closure query
rdmarsh2 Jul 12, 2023
8120c8b
Swift: refactor to remove cartesian product
rdmarsh2 Jul 12, 2023
459eea5
Swift: avoid implicit return in tests
rdmarsh2 Jul 12, 2023
f125fa2
Swift: respond to PR comments
rdmarsh2 Jul 13, 2023
5f39a1a
Swift: qhelp for UnsafePointerEscapesClosure
rdmarsh2 Jul 13, 2023
37d69e5
Swift: add change note for unsafe closure query
rdmarsh2 Jul 13, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
111 changes: 9 additions & 102 deletions swift/ql/test/query-tests/Security/CWE-825/UnsafePointerEscapesClosure.expected
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,120 +1,27 @@
edges
| file://:0:0:0:0 | [post] self [field, some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] |
| file://:0:0:0:0 | [post] self [field, some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0, some:0, some:0, some:0] |
| file://:0:0:0:0 | [post] self [field, some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] |
| file://:0:0:0:0 | [post] self [field, some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0, some:0, some:0] |
| file://:0:0:0:0 | [post] self [field, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] |
| file://:0:0:0:0 | [post] self [field, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0, some:0] |
| file://:0:0:0:0 | [post] self [field, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] |
| file://:0:0:0:0 | [post] self [field, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0] |
| file://:0:0:0:0 | [post] self [field] | withUnsafeBytes.swift:33:9:33:9 | self[return] |
| file://:0:0:0:0 | [post] self [field] | withUnsafeBytes.swift:33:9:33:9 | self[return] [field] |
| file://:0:0:0:0 | value | file://:0:0:0:0 | [post] self [field] |
| file://:0:0:0:0 | value [some:0, some:0, some:0, some:0] | file://:0:0:0:0 | [post] self [field, some:0, some:0, some:0, some:0] |
| file://:0:0:0:0 | value [some:0, some:0, some:0] | file://:0:0:0:0 | [post] self [field, some:0, some:0, some:0] |
| file://:0:0:0:0 | value [some:0, some:0] | file://:0:0:0:0 | [post] self [field, some:0, some:0] |
| file://:0:0:0:0 | value [some:0] | file://:0:0:0:0 | [post] self [field, some:0] |
| withUnsafeBytes.swift:9:25:9:25 | $0 | withUnsafeBytes.swift:10:16:10:16 | $0 |
| withUnsafeBytes.swift:13:34:13:37 | p | withUnsafeBytes.swift:13:97:13:97 | p |
| withUnsafeBytes.swift:15:34:15:37 | p | withUnsafeBytes.swift:15:109:15:109 | p |
| withUnsafeBytes.swift:15:109:15:109 | p | withUnsafeBytes.swift:15:97:15:110 | call to id(pointer:) |
| withUnsafeBytes.swift:15:109:15:109 | p | withUnsafeBytes.swift:28:12:28:21 | pointer |
| withUnsafeBytes.swift:20:28:20:31 | p | withUnsafeBytes.swift:20:68:20:68 | p |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field] |
| withUnsafeBytes.swift:20:68:20:68 | p | withUnsafeBytes.swift:20:68:20:68 | p [some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p | withUnsafeBytes.swift:33:9:33:9 | value |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0] | withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0] | withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0] | withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0] |
| withUnsafeBytes.swift:28:12:28:21 | pointer | withUnsafeBytes.swift:29:12:29:12 | pointer |
| withUnsafeBytes.swift:28:12:28:21 | pointer | withUnsafeBytes.swift:29:12:29:12 | pointer |
| withUnsafeBytes.swift:33:9:33:9 | value | file://:0:0:0:0 | value |
| withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0, some:0] | file://:0:0:0:0 | value [some:0, some:0, some:0, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0] | file://:0:0:0:0 | value [some:0, some:0, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0] | file://:0:0:0:0 | value [some:0, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | value [some:0] | file://:0:0:0:0 | value [some:0] |
| withUnsafeBytes.swift:15:109:15:109 | p | withUnsafeBytes.swift:38:12:38:21 | pointer |
| withUnsafeBytes.swift:38:12:38:21 | pointer | withUnsafeBytes.swift:39:12:39:12 | pointer |
| withUnsafeBytes.swift:38:12:38:21 | pointer | withUnsafeBytes.swift:39:12:39:12 | pointer |
nodes
| file://:0:0:0:0 | [post] self [field, some:0, some:0, some:0, some:0] | semmle.label | [post] self [field, some:0, some:0, some:0, some:0] |
| file://:0:0:0:0 | [post] self [field, some:0, some:0, some:0] | semmle.label | [post] self [field, some:0, some:0, some:0] |
| file://:0:0:0:0 | [post] self [field, some:0, some:0] | semmle.label | [post] self [field, some:0, some:0] |
| file://:0:0:0:0 | [post] self [field, some:0] | semmle.label | [post] self [field, some:0] |
| file://:0:0:0:0 | [post] self [field] | semmle.label | [post] self [field] |
| file://:0:0:0:0 | value | semmle.label | value |
| file://:0:0:0:0 | value [some:0, some:0, some:0, some:0] | semmle.label | value [some:0, some:0, some:0, some:0] |
| file://:0:0:0:0 | value [some:0, some:0, some:0] | semmle.label | value [some:0, some:0, some:0] |
| file://:0:0:0:0 | value [some:0, some:0] | semmle.label | value [some:0, some:0] |
| file://:0:0:0:0 | value [some:0] | semmle.label | value [some:0] |
| withUnsafeBytes.swift:9:25:9:25 | $0 | semmle.label | $0 |
| withUnsafeBytes.swift:10:16:10:16 | $0 | semmle.label | $0 |
| withUnsafeBytes.swift:13:34:13:37 | p | semmle.label | p |
| withUnsafeBytes.swift:13:97:13:97 | p | semmle.label | p |
| withUnsafeBytes.swift:15:34:15:37 | p | semmle.label | p |
| withUnsafeBytes.swift:15:97:15:110 | call to id(pointer:) | semmle.label | call to id(pointer:) |
| withUnsafeBytes.swift:15:109:15:109 | p | semmle.label | p |
| withUnsafeBytes.swift:20:28:20:31 | p | semmle.label | p |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... | semmle.label | ... = ... |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0, some:0, some:0] | semmle.label | ... = ... [field, some:0, some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0, some:0] | semmle.label | ... = ... [field, some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0] | semmle.label | ... = ... [field, some:0, some:0] |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0] | semmle.label | ... = ... [field, some:0] |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... [field] | semmle.label | ... = ... [field] |
| withUnsafeBytes.swift:20:68:20:68 | p | semmle.label | p |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0, some:0] | semmle.label | p [some:0, some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0] | semmle.label | p [some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0] | semmle.label | p [some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0] | semmle.label | p [some:0] |
| withUnsafeBytes.swift:28:12:28:21 | pointer | semmle.label | pointer |
| withUnsafeBytes.swift:28:12:28:21 | pointer | semmle.label | pointer |
| withUnsafeBytes.swift:29:12:29:12 | pointer | semmle.label | pointer |
| withUnsafeBytes.swift:29:12:29:12 | pointer | semmle.label | pointer |
| withUnsafeBytes.swift:33:9:33:9 | self[return] | semmle.label | self[return] |
| withUnsafeBytes.swift:33:9:33:9 | self[return] | semmle.label | self[return] |
| withUnsafeBytes.swift:33:9:33:9 | self[return] | semmle.label | self[return] |
| withUnsafeBytes.swift:33:9:33:9 | self[return] | semmle.label | self[return] |
| withUnsafeBytes.swift:33:9:33:9 | self[return] | semmle.label | self[return] |
| withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0, some:0, some:0, some:0] | semmle.label | self[return] [field, some:0, some:0, some:0, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0, some:0, some:0] | semmle.label | self[return] [field, some:0, some:0, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0, some:0] | semmle.label | self[return] [field, some:0, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0] | semmle.label | self[return] [field, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | self[return] [field] | semmle.label | self[return] [field] |
| withUnsafeBytes.swift:33:9:33:9 | value | semmle.label | value |
| withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0, some:0] | semmle.label | value [some:0, some:0, some:0, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0] | semmle.label | value [some:0, some:0, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0] | semmle.label | value [some:0, some:0] |
| withUnsafeBytes.swift:33:9:33:9 | value [some:0] | semmle.label | value [some:0] |
| withUnsafeBytes.swift:38:12:38:21 | pointer | semmle.label | pointer |
| withUnsafeBytes.swift:38:12:38:21 | pointer | semmle.label | pointer |
| withUnsafeBytes.swift:39:12:39:12 | pointer | semmle.label | pointer |
| withUnsafeBytes.swift:39:12:39:12 | pointer | semmle.label | pointer |
subpaths
| withUnsafeBytes.swift:15:109:15:109 | p | withUnsafeBytes.swift:28:12:28:21 | pointer | withUnsafeBytes.swift:29:12:29:12 | pointer | withUnsafeBytes.swift:15:97:15:110 | call to id(pointer:) |
| withUnsafeBytes.swift:20:68:20:68 | p | withUnsafeBytes.swift:33:9:33:9 | value | withUnsafeBytes.swift:33:9:33:9 | self[return] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p | withUnsafeBytes.swift:33:9:33:9 | value | withUnsafeBytes.swift:33:9:33:9 | self[return] [field] | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0, some:0, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0, some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0, some:0] |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] | withUnsafeBytes.swift:20:58:20:68 | ... = ... |
| withUnsafeBytes.swift:20:68:20:68 | p [some:0] | withUnsafeBytes.swift:33:9:33:9 | value [some:0] | withUnsafeBytes.swift:33:9:33:9 | self[return] [field, some:0] | withUnsafeBytes.swift:20:58:20:68 | ... = ... [field, some:0] |
| withUnsafeBytes.swift:15:109:15:109 | p | withUnsafeBytes.swift:38:12:38:21 | pointer | withUnsafeBytes.swift:39:12:39:12 | pointer | withUnsafeBytes.swift:15:97:15:110 | call to id(pointer:) |
#select
| withUnsafeBytes.swift:10:16:10:16 | $0 | withUnsafeBytes.swift:9:25:9:25 | $0 | withUnsafeBytes.swift:10:16:10:16 | $0 | This unsafe parameter may escape its invocation |
| withUnsafeBytes.swift:13:97:13:97 | p | withUnsafeBytes.swift:13:34:13:37 | p | withUnsafeBytes.swift:13:97:13:97 | p | This unsafe parameter may escape its invocation |
| withUnsafeBytes.swift:15:97:15:110 | call to id(pointer:) | withUnsafeBytes.swift:15:34:15:37 | p | withUnsafeBytes.swift:15:97:15:110 | call to id(pointer:) | This unsafe parameter may escape its invocation |
| withUnsafeBytes.swift:20:58:20:68 | ... = ... | withUnsafeBytes.swift:20:28:20:31 | p | withUnsafeBytes.swift:20:58:20:68 | ... = ... | This unsafe parameter may escape its invocation |
| withUnsafeBytes.swift:29:12:29:12 | pointer | withUnsafeBytes.swift:28:12:28:21 | pointer | withUnsafeBytes.swift:29:12:29:12 | pointer | This unsafe parameter may escape its invocation |
| withUnsafeBytes.swift:39:12:39:12 | pointer | withUnsafeBytes.swift:38:12:38:21 | pointer | withUnsafeBytes.swift:39:12:39:12 | pointer | This unsafe parameter may escape its invocation |
12 changes: 11 additions & 1 deletion swift/ql/test/query-tests/Security/CWE-825/withUnsafeBytes.swift
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -17,12 +17,22 @@ func arrayTest() {
ints.withUnsafeBytes({(p: UnsafeRawBufferPointer) in print(p)}) // GOOD

var v = PointerHolder()
ints.withUnsafeBytes({(p: UnsafeRawBufferPointer) in v.field = p}) // BAD
ints.withUnsafeBytes({(p: UnsafeRawBufferPointer) in
v.field = p
return 1
}) // BAD
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

What's the issue with implicit returns? Surely we will see them in real world code.

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The issue is that we were picking up the implicit return of the assignment, but not the field being assigned. This is currently not detected... I think there's some missing flow for closure captures.

print(v.field)

ints.withUnsafeBytes(myPrint) // GOOD
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Another variant here would be calling a member function that stores the pointer argument in the object it's called on for later use. The effect is similar to the v.field = p case.


myPrint(p: ints.withUnsafeBytes(id)) // BAD

var v2: UnsafeRawBufferPointer? = nil
ints.withUnsafeBytes({(p: UnsafeRawBufferPointer) in
v2 = p
return 1
}) // BAD
print(v2)
}

func id<T>(pointer: T) -> T {
Expand Down