diff options
Diffstat (limited to 'kernels/linux-libre-pae/0001-x86-x32-Correct-invalid-use-of-user-timespec-in-the-.patch')
| -rw-r--r-- | kernels/linux-libre-pae/0001-x86-x32-Correct-invalid-use-of-user-timespec-in-the-.patch | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/kernels/linux-libre-pae/0001-x86-x32-Correct-invalid-use-of-user-timespec-in-the-.patch b/kernels/linux-libre-pae/0001-x86-x32-Correct-invalid-use-of-user-timespec-in-the-.patch new file mode 100644 index 000000000..3f1bccc80 --- /dev/null +++ b/kernels/linux-libre-pae/0001-x86-x32-Correct-invalid-use-of-user-timespec-in-the-.patch @@ -0,0 +1,80 @@ +From 2def2ef2ae5f3990aabdbe8a755911902707d268 Mon Sep 17 00:00:00 2001 +From: PaX Team <pageexec@freemail.hu> +Date: Thu, 30 Jan 2014 16:59:25 -0800 +Subject: [PATCH] x86, x32: Correct invalid use of user timespec in the kernel + +The x32 case for the recvmsg() timout handling is broken: + + asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg, + unsigned int vlen, unsigned int flags, + struct compat_timespec __user *timeout) + { + int datagrams; + struct timespec ktspec; + + if (flags & MSG_CMSG_COMPAT) + return -EINVAL; + + if (COMPAT_USE_64BIT_TIME) + return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, + flags | MSG_CMSG_COMPAT, + (struct timespec *) timeout); + ... + +The timeout pointer parameter is provided by userland (hence the __user +annotation) but for x32 syscalls it's simply cast to a kernel pointer +and is passed to __sys_recvmmsg which will eventually directly +dereference it for both reading and writing. Other callers to +__sys_recvmmsg properly copy from userland to the kernel first. + +The bug was introduced by commit ee4fa23c4bfc ("compat: Use +COMPAT_USE_64BIT_TIME in net/compat.c") and should affect all kernels +since 3.4 (and perhaps vendor kernels if they backported x32 support +along with this code). + +Note that CONFIG_X86_X32_ABI gets enabled at build time and only if +CONFIG_X86_X32 is enabled and ld can build x32 executables. + +Other uses of COMPAT_USE_64BIT_TIME seem fine. + +This addresses CVE-2014-0038. + +Signed-off-by: PaX Team <pageexec@freemail.hu> +Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> +Cc: <stable@vger.kernel.org> # v3.4+ +Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> +--- + net/compat.c | 9 ++------- + 1 file changed, 2 insertions(+), 7 deletions(-) + +diff --git a/net/compat.c b/net/compat.c +index dd32e34..f50161f 100644 +--- a/net/compat.c ++++ b/net/compat.c +@@ -780,21 +780,16 @@ asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg, + if (flags & MSG_CMSG_COMPAT) + return -EINVAL; + +- if (COMPAT_USE_64BIT_TIME) +- return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, +- flags | MSG_CMSG_COMPAT, +- (struct timespec *) timeout); +- + if (timeout == NULL) + return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, + flags | MSG_CMSG_COMPAT, NULL); + +- if (get_compat_timespec(&ktspec, timeout)) ++ if (compat_get_timespec(&ktspec, timeout)) + return -EFAULT; + + datagrams = __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, + flags | MSG_CMSG_COMPAT, &ktspec); +- if (datagrams > 0 && put_compat_timespec(&ktspec, timeout)) ++ if (datagrams > 0 && compat_put_timespec(&ktspec, timeout)) + datagrams = -EFAULT; + + return datagrams; +-- +1.8.5.3 + |