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| author | Andrew Morton <akpm@osdl.org> | 2005-08-09 15:29:19 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2005-08-09 15:29:19 -0700 |
| commit | d64d3873721cfe870d49d73c3744f06260779ce7 (patch) | |
| tree | b49a930e65ed4f30b4f8f2aac4ddb08c41bc4b79 /net/compat.c | |
| parent | 3501466941347f0e1992b2672affb3feb92925fd (diff) | |
| download | linux-d64d3873721cfe870d49d73c3744f06260779ce7.tar.gz linux-d64d3873721cfe870d49d73c3744f06260779ce7.tar.bz2 linux-d64d3873721cfe870d49d73c3744f06260779ce7.zip | |
[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/compat.c')
| -rw-r--r-- | net/compat.c | 9 |
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), - GFP_KERNEL); - if(!kern_iov) - return -ENOMEM; - } - tot_len = iov_from_user_compat_to_kern(kern_iov, (struct compat_iovec __user *)kern_msg->msg_iov, kern_msg->msg_iovlen); if(tot_len >= 0) kern_msg->msg_iov = kern_iov; - else if(kern_msg->msg_iovlen > UIO_FASTIOV) - kfree(kern_iov); return tot_len; } |