From: Dmitry V. Levin <ldv@altlinux.org>
Date: Thu, 16 Nov 2017 00:12:46 +0000 (+0000)
Subject: net: fix decoding of optval argument of [gs]etsockopt SOL_NETLINK
X-Git-Tag: v4.21~314
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=8a7030f20a79dd8368defb03fd8b74aff210ac1d;p=strace

net: fix decoding of optval argument of [gs]etsockopt SOL_NETLINK

Tweak the parser to follow the kernel behaviour.

* net.c (print_getsockopt, print_setsockopt) <SOL_NETLINK>: Fetch and
print returned value as integer iff the length is >= sizeof(int),
otherwise print the address.
* NEWS: Mention this.
---

diff --git a/NEWS b/NEWS
index 078449ca..87b85c7d 100644
--- a/NEWS
+++ b/NEWS
@@ -3,8 +3,8 @@ Noteworthy changes in release ?.?? (????-??-??)
 
 * Improvements
   * Implemented decoding of netlink descriptor attributes as file descriptors.
-  * Implemented decoding of option name argument of getsockopt and setsockopt
-    syscalls for SOL_NETLINK level.
+  * Enhanced decoding of getsockopt and setsockopt syscalls for SOL_NETLINK
+    level.
   * Updated the list of MSG_* constants.
 
 Noteworthy changes in release 4.20 (2017-11-13)
diff --git a/net.c b/net.c
index f3c6f6b8..3e355e38 100644
--- a/net.c
+++ b/net.c
@@ -601,6 +601,13 @@ print_getsockopt(struct tcb *const tcp, const unsigned int level,
 			return;
 		}
 		break;
+
+	case SOL_NETLINK:
+		if (len < (int) sizeof(int))
+			printaddr(addr);	/* unlikely */
+		else
+			printnum_int(tcp, addr, "%d");
+		return;
 	}
 
 	/* default arg printing */
@@ -825,6 +832,13 @@ print_setsockopt(struct tcb *const tcp, const unsigned int level,
 			return;
 		}
 		break;
+
+	case SOL_NETLINK:
+		if (len < (int) sizeof(int))
+			printaddr(addr);
+		else
+			printnum_int(tcp, addr, "%d");
+		return;
 	}
 
 	/* default arg printing */