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| author | Catalin Marinas <catalin.marinas@arm.com> | 2015-03-20 16:48:13 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-03-26 15:00:56 +0100 |
| commit | 281c9c3601b69f1fbc492beb5976e1e2685854de (patch) | |
| tree | c8699c69f167f65b87cd75f16d0fb0931764464d | |
| parent | 175ff19c37149c352e3b983a8d78add034aef36f (diff) | |
| download | lwn-281c9c3601b69f1fbc492beb5976e1e2685854de.tar.gz lwn-281c9c3601b69f1fbc492beb5976e1e2685854de.zip | |
net: compat: Update get_compat_msghdr() to match copy_msghdr_from_user() behaviour
[ Upstream commit 91edd096e224941131f896b86838b1e59553696a ]
Commit db31c55a6fb2 (net: clamp ->msg_namelen instead of returning an
error) introduced the clamping of msg_namelen when the unsigned value
was larger than sizeof(struct sockaddr_storage). This caused a
msg_namelen of -1 to be valid. The native code was subsequently fixed by
commit dbb490b96584 (net: socket: error on a negative msg_namelen).
In addition, the native code sets msg_namelen to 0 when msg_name is
NULL. This was done in commit (6a2a2b3ae075 net:socket: set msg_namelen
to 0 if msg_name is passed as NULL in msghdr struct from userland) and
subsequently updated by 08adb7dabd48 (fold verify_iovec() into
copy_msghdr_from_user()).
This patch brings the get_compat_msghdr() in line with
copy_msghdr_from_user().
Fixes: db31c55a6fb2 (net: clamp ->msg_namelen instead of returning an error)
Cc: David S. Miller <davem@davemloft.net>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/compat.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/net/compat.c b/net/compat.c index 275af79c131b..d12529050b29 100644 --- a/net/compat.c +++ b/net/compat.c @@ -71,6 +71,13 @@ int get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg) __get_user(kmsg->msg_controllen, &umsg->msg_controllen) || __get_user(kmsg->msg_flags, &umsg->msg_flags)) return -EFAULT; + + if (!tmp1) + kmsg->msg_namelen = 0; + + if (kmsg->msg_namelen < 0) + return -EINVAL; + if (kmsg->msg_namelen > sizeof(struct sockaddr_storage)) kmsg->msg_namelen = sizeof(struct sockaddr_storage); kmsg->msg_name = compat_ptr(tmp1); |