diff options
Diffstat (limited to 'cdrom-use-kzalloc-for-failing-hardware.patch')
| -rw-r--r-- | cdrom-use-kzalloc-for-failing-hardware.patch | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/cdrom-use-kzalloc-for-failing-hardware.patch b/cdrom-use-kzalloc-for-failing-hardware.patch new file mode 100644 index 000000000..6afb6c4d8 --- /dev/null +++ b/cdrom-use-kzalloc-for-failing-hardware.patch @@ -0,0 +1,45 @@ +From 050e4b8fb7cdd7096c987a9cd556029c622c7fe2 Mon Sep 17 00:00:00 2001 +From: Jonathan Salwan <jonathan.salwan@gmail.com> +Date: Thu, 06 Jun 2013 00:39:39 +0000 +Subject: drivers/cdrom/cdrom.c: use kzalloc() for failing hardware + +In drivers/cdrom/cdrom.c mmc_ioctl_cdrom_read_data() allocates a memory +area with kmalloc in line 2885. + +2885 cgc->buffer = kmalloc(blocksize, GFP_KERNEL); +2886 if (cgc->buffer == NULL) +2887 return -ENOMEM; + +In line 2908 we can find the copy_to_user function: + +2908 if (!ret && copy_to_user(arg, cgc->buffer, blocksize)) + +The cgc->buffer is never cleaned and initialized before this function. If +ret = 0 with the previous basic block, it's possible to display some +memory bytes in kernel space from userspace. + +When we read a block from the disk it normally fills the ->buffer but if +the drive is malfunctioning there is a chance that it would only be +partially filled. The result is an leak information to userspace. + +Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> +Cc: Jens Axboe <axboe@kernel.dk> +Signed-off-by: Andrew Morton <akpm@linux-foundation.org> +--- +(limited to 'drivers/cdrom/cdrom.c') + +diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c +index d620b44..8a3aff7 100644 +--- a/drivers/cdrom/cdrom.c ++++ b/drivers/cdrom/cdrom.c +@@ -2882,7 +2882,7 @@ static noinline int mmc_ioctl_cdrom_read_data(struct cdrom_device_info *cdi, + if (lba < 0) + return -EINVAL; + +- cgc->buffer = kmalloc(blocksize, GFP_KERNEL); ++ cgc->buffer = kzalloc(blocksize, GFP_KERNEL); + if (cgc->buffer == NULL) + return -ENOMEM; + +-- +cgit v0.9.2 |