2.6.35-longterm review patch. If anyone has any objections, please let me know.
------------------ From: Dan Rosenberg <[email protected]> [ upstream commit a1f74ae82d133ebb2aabb19d181944b4e83e9960 ] At two points in handling device ioctls via /dev/mpt2ctl, user-supplied length values are used to copy data from userspace into heap buffers without bounds checking, allowing controllable heap corruption and subsequently privilege escalation. Additionally, user-supplied values are used to determine the size of a copy_to_user() as well as the offset into the buffer to be read, with no bounds checking, allowing users to read arbitrary kernel memory. Signed-off-by: Dan Rosenberg <[email protected]> Cc: [email protected] Acked-by: Eric Moore <[email protected]> Signed-off-by: James Bottomley <[email protected]> Signed-off-by: Andi Kleen <[email protected]> Index: linux-2.6.35.y/drivers/scsi/mpt2sas/mpt2sas_ctl.c =================================================================== --- linux-2.6.35.y.orig/drivers/scsi/mpt2sas/mpt2sas_ctl.c +++ linux-2.6.35.y/drivers/scsi/mpt2sas/mpt2sas_ctl.c @@ -637,6 +637,13 @@ _ctl_do_mpt_command(struct MPT2SAS_ADAPT data_out_sz = karg.data_out_size; data_in_sz = karg.data_in_size; + /* Check for overflow and wraparound */ + if (karg.data_sge_offset * 4 > ioc->request_sz || + karg.data_sge_offset > (UINT_MAX / 4)) { + ret = -EINVAL; + goto out; + } + /* copy in request message frame from user */ if (copy_from_user(mpi_request, mf, karg.data_sge_offset*4)) { printk(KERN_ERR "failure at %s:%d/%s()!\n", __FILE__, __LINE__, @@ -1883,7 +1890,7 @@ _ctl_diag_read_buffer(void __user *arg, Mpi2DiagBufferPostReply_t *mpi_reply; int rc, i; u8 buffer_type; - unsigned long timeleft; + unsigned long timeleft, request_size, copy_size; u16 smid; u16 ioc_status; u8 issue_reset = 0; @@ -1919,6 +1926,8 @@ _ctl_diag_read_buffer(void __user *arg, return -ENOMEM; } + request_size = ioc->diag_buffer_sz[buffer_type]; + if ((karg.starting_offset % 4) || (karg.bytes_to_read % 4)) { printk(MPT2SAS_ERR_FMT "%s: either the starting_offset " "or bytes_to_read are not 4 byte aligned\n", ioc->name, @@ -1926,13 +1935,23 @@ _ctl_diag_read_buffer(void __user *arg, return -EINVAL; } + if (karg.starting_offset > request_size) + return -EINVAL; + diag_data = (void *)(request_data + karg.starting_offset); dctlprintk(ioc, printk(MPT2SAS_DEBUG_FMT "%s: diag_buffer(%p), " "offset(%d), sz(%d)\n", ioc->name, __func__, diag_data, karg.starting_offset, karg.bytes_to_read)); + /* Truncate data on requests that are too large */ + if ((diag_data + karg.bytes_to_read < diag_data) || + (diag_data + karg.bytes_to_read > request_data + request_size)) + copy_size = request_size - karg.starting_offset; + else + copy_size = karg.bytes_to_read; + if (copy_to_user((void __user *)uarg->diagnostic_data, - diag_data, karg.bytes_to_read)) { + diag_data, copy_size)) { printk(MPT2SAS_ERR_FMT "%s: Unable to write " "mpt_diag_read_buffer_t data @ %p\n", ioc->name, __func__, diag_data); _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
