TheArchive/tailscale
1
0
Fork 0
mirror of https://github.com/tailscale/tailscale.git synced 2025-03-24 02:01:01 +00:00
Code Issues Packages Projects Releases Wiki Activity

net/netstat: add nil checks to Windows OSMetadata implementation

Browse Source 
The API documentation does claim to output empty strings under certain
conditions, but we're sometimes seeing nil pointers in the wild, not empty
strings.

Fixes https://github.com/tailscale/corp/issues/8878

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
This commit is contained in:
Aaron Klotz 2023-01-27 09:31:00 -07:00
parent 8c03a31d10
commit 4a869048bf
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
net/netstat/netstat_windows.go
View File

@ -224,6 +224,7 @@ type moduleInfoConstraint interface {
_MIB_TCPROW_OWNER_MODULE | _MIB_TCP6ROW_OWNER_MODULE
}
// moduleInfo may return "", nil indicating a successful call but with empty data
func moduleInfo[entryType moduleInfoConstraint](entry *entryType, proc *windows.LazyProc) (string, error) {
var buf []byte
var desiredLen uint32
@ -249,6 +250,12 @@ func moduleInfo[entryType moduleInfoConstraint](entry *entryType, proc *windows.
}
basicInfo := (*_TCPIP_OWNER_MODULE_BASIC_INFO)(addr)
// GetOwnerModuleFromTcp*Entry is apparently using nil as an empty result
// under certain circumstances, so we check all the things.
if basicInfo == nil || basicInfo.moduleName == nil {
return "", nil
}
return windows.UTF16PtrToString(basicInfo.moduleName), nil
}