path: root/net
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authorAndrew Morton <akpm@osdl.org>2005-08-09 15:29:19 -0700
committerDavid S. Miller <davem@davemloft.net>2005-08-09 15:29:19 -0700
commitd64d3873721cfe870d49d73c3744f06260779ce7 (patch)
treeb49a930e65ed4f30b4f8f2aac4ddb08c41bc4b79 /net
parent3501466941347f0e1992b2672affb3feb92925fd (diff)
[NET]: Fix memory leak in sys_{send,recv}msg() w/compat
From: Dave Johnson <djohnson+linux-kernel@sw.starentnetworks.com> sendmsg()/recvmsg() syscalls from o32/n32 apps to a 64bit kernel will cause a kernel memory leak if iov_len > UIO_FASTIOV for each syscall! This is because both sys_sendmsg() and verify_compat_iovec() kmalloc a new iovec structure. Only the one from sys_sendmsg() is free'ed. I wrote a simple test program to confirm this after identifying the problem: http://davej.org/programs/testsendmsg.c Note that the below fix will break solaris_sendmsg()/solaris_recvmsg() as it also calls verify_compat_iovec() but expects it to malloc internally. [ I fixed that. -DaveM ] Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
1 files changed, 0 insertions, 9 deletions
diff --git a/net/compat.c b/net/compat.c
index be5d936dc423..d99ab9695893 100644
--- a/net/compat.c
+++ b/net/compat.c
@@ -91,20 +91,11 @@ int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *kern_iov,
} else
kern_msg->msg_name = NULL;
- if(kern_msg->msg_iovlen > UIO_FASTIOV) {
- kern_iov = kmalloc(kern_msg->msg_iovlen * sizeof(struct iovec),
- if(!kern_iov)
- return -ENOMEM;
- }
tot_len = iov_from_user_compat_to_kern(kern_iov,
(struct compat_iovec __user *)kern_msg->msg_iov,
if(tot_len >= 0)
kern_msg->msg_iov = kern_iov;
- else if(kern_msg->msg_iovlen > UIO_FASTIOV)
- kfree(kern_iov);
return tot_len;

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