diff options
| author | Bart Van Assche <bart.vanassche@sandisk.com> | 2016-06-28 17:36:46 +0300 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2016-07-01 17:54:11 +0300 |
| commit | 028b39e314dd8b4ab8d3ac401285db40ab1f39d8 (patch) | |
| tree | 2166607510865429e81e9a7ad52062f9817a919d /drivers/md | |
| parent | 350b53932810840a0c68467d7d78795010929940 (diff) | |
| download | linux-028b39e314dd8b4ab8d3ac401285db40ab1f39d8.tar.xz | |
dm ioctl: Simplify parameter buffer management code
Merge the two DM_PARAMS_[KV]MALLOC flags into a single flag.
Doing so avoids the crashes seen with previous attempts to consolidate
buffer management to use kvfree() without first flagging that memory had
actually been allocated.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-ioctl.c | 18 |
1 files changed, 6 insertions, 12 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index b59e34595ad8..96df89a31f42 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -1670,8 +1670,7 @@ static int check_version(unsigned int cmd, struct dm_ioctl __user *user) return r; } -#define DM_PARAMS_KMALLOC 0x0001 /* Params alloced with kmalloc */ -#define DM_PARAMS_VMALLOC 0x0002 /* Params alloced with vmalloc */ +#define DM_PARAMS_MALLOC 0x0001 /* Params allocated with kvmalloc() */ #define DM_WIPE_BUFFER 0x0010 /* Wipe input buffer before returning from ioctl */ static void free_params(struct dm_ioctl *param, size_t param_size, int param_flags) @@ -1679,10 +1678,8 @@ static void free_params(struct dm_ioctl *param, size_t param_size, int param_fla if (param_flags & DM_WIPE_BUFFER) memset(param, 0, param_size); - if (param_flags & DM_PARAMS_KMALLOC) - kfree(param); - if (param_flags & DM_PARAMS_VMALLOC) - vfree(param); + if (param_flags & DM_PARAMS_MALLOC) + kvfree(param); } static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kernel, @@ -1714,19 +1711,14 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kern * Use kmalloc() rather than vmalloc() when we can. */ dmi = NULL; - if (param_kernel->data_size <= KMALLOC_MAX_SIZE) { + if (param_kernel->data_size <= KMALLOC_MAX_SIZE) dmi = kmalloc(param_kernel->data_size, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN); - if (dmi) - *param_flags |= DM_PARAMS_KMALLOC; - } if (!dmi) { unsigned noio_flag; noio_flag = memalloc_noio_save(); dmi = __vmalloc(param_kernel->data_size, GFP_NOIO | __GFP_HIGH | __GFP_HIGHMEM, PAGE_KERNEL); memalloc_noio_restore(noio_flag); - if (dmi) - *param_flags |= DM_PARAMS_VMALLOC; } if (!dmi) { @@ -1735,6 +1727,8 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kern return -ENOMEM; } + *param_flags |= DM_PARAMS_MALLOC; + if (copy_from_user(dmi, user, param_kernel->data_size)) goto bad; |