Skip to content

Fix Dot11InformationElement parsing panic #124

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

Merged
mosajjal merged 1 commit into from
Aug 31, 2025
Merged

Fix Dot11InformationElement parsing panic #124

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
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
15 changes: 15 additions & 0 deletions layers/dot11.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1595,6 +1595,15 @@ func (m *Dot11InformationElement) NextLayerType() gopacket.LayerType {
return LayerTypeDot11InformationElement
}

func checkOffsetLength(start int, end int, df *gopacket.DecodeFeedback) error {
if start > end {
(*df).SetTruncated()
return fmt.Errorf("information element length %v too short, %v required", end, start)
}

return nil
}

func (m *Dot11InformationElement) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
if len(data) < 2 {
df.SetTruncated()
Expand All @@ -1617,9 +1626,15 @@ func (m *Dot11InformationElement) DecodeFromBytes(data []byte, df gopacket.Decod

// Vendor extension
m.OUI = data[offset : offset+4]
if err := checkOffsetLength(offset+4, offset+int(m.Length), &df); err != nil {
return err
}
m.Info = data[offset+4 : offset+int(m.Length)]
} else if m.ID == 255 {
m.ExtensionID = Dot11InformationElementExtId(data[offset])
if err := checkOffsetLength(offset+1, offset+int(m.Length), &df); err != nil {
return err
}
m.Info = data[offset+1 : offset+int(m.Length)]
} else {
m.Info = data[offset : offset+int(m.Length)]
Expand Down
10 changes: 10 additions & 0 deletions layers/dot11_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -816,6 +816,16 @@ func TestDot11InformationElement(t *testing.T) {
},
errors.New("vendor extension size < 4"),
},
{
"Offset greater than len",
[]byte{0xdd, 0x03, 0x00, 0x50, 0xf2, 0x01, 0x02, 0x03, 0x04, 0x05},
Dot11InformationElement{
ID: 221,
Length: 3,
Info: []byte{},
},
errors.New("information element length 5 too short, 6 required"),
},
}

for _, test := range cases {
Expand Down
Loading