luc14n0/glib
1
0
Fork 0
mirror of https://gitlab.gnome.org/GNOME/glib.git synced 2024-09-20 01:06:15 +02:00
Code Issues Packages Projects Releases Wiki Activity

Detect "empty" socket credentials on Linux

Browse Source 
Linux uses struct ucred to pass over socket credentials. Historically
this has always worked in recievemsg, if SO_PASSCRED was set on the socket,
even if the remote side didn't pass any credits. But this change broke that:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=16e5726269611b71c930054ffe9b858c1cea88eb;hp=a9e9fd7182332d0cf5f3e601df3e71dd431b70d7

However, it doesn't actually fail getting the credentials, it just returns
an "empty" one, as initialized by cred_to_ucred() at:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=net/core/sock.c;h=b29ab61b029cf7f76fda992ecfcb8dcaa06b0483;#l756

So, we detect this and fail the credentials reading.

This actually happened in real life with gdbus acting as a server, as
gdbus expected an ucred but libdbus didn't send one.
This commit is contained in:
Alexander Larsson 2012-04-12 16:43:49 +02:00
parent 69d929e67f
commit ec91ed00f1
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
gio/gunixcredentialsmessage.c
View File

@ -144,6 +144,13 @@ g_unix_credentials_message_deserialize (gint level,
ucred = data;
if (ucred->uid == (uid_t)-1 &&
ucred->gid == (gid_t)-1)
{
/* This happens if the remote side didn't pass the credentials */
goto out;
}
credentials = g_credentials_new ();
g_credentials_set_native (credentials, G_CREDENTIALS_TYPE_LINUX_UCRED, ucred);
message = g_unix_credentials_message_new_with_credentials (credentials);