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| author | Dan Rosenberg <drosenberg@vsecurity.com> | 2011-04-05 20:45:59 +0400 |
|---|---|---|
| committer | James Bottomley <James.Bottomley@suse.de> | 2011-04-24 20:01:59 +0400 |
| commit | a1f74ae82d133ebb2aabb19d181944b4e83e9960 (patch) | |
| tree | 88f1834f08d0a5def17889a40855f72bd8bd3927 /drivers/scsi | |
| parent | 686c4cbb10fc0e75b29b097290b4f7fc3f010b9e (diff) | |
| download | linux-a1f74ae82d133ebb2aabb19d181944b4e83e9960.tar.xz | |
[SCSI] mpt2sas: prevent heap overflows and unchecked reads
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 <drosenberg@vsecurity.com>
Cc: stable@kernel.org
Acked-by: Eric Moore <eric.moore@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/mpt2sas/mpt2sas_ctl.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/drivers/scsi/mpt2sas/mpt2sas_ctl.c b/drivers/scsi/mpt2sas/mpt2sas_ctl.c index 1c6d2b405eef..d72f1f2b1392 100644 --- a/drivers/scsi/mpt2sas/mpt2sas_ctl.c +++ b/drivers/scsi/mpt2sas/mpt2sas_ctl.c @@ -688,6 +688,13 @@ _ctl_do_mpt_command(struct MPT2SAS_ADAPTER *ioc, goto out; } + /* 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__, @@ -1963,7 +1970,7 @@ _ctl_diag_read_buffer(void __user *arg, enum block_state state) 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; @@ -1999,6 +2006,8 @@ _ctl_diag_read_buffer(void __user *arg, enum block_state state) 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, @@ -2006,13 +2015,23 @@ _ctl_diag_read_buffer(void __user *arg, enum block_state state) return -EINVAL; } + if (karg.starting_offset > request_size) + return -EINVAL; + diag_data = (void *)(request_data + karg.starting_offset); dctlprintk(ioc, printk(MPT2SAS_INFO_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); |