On 02/27/2018 11:45 PM, David Sterba wrote:
On Mon, Feb 26, 2018 at 10:47:04AM +0800, Anand Jain wrote:
We aren't verifying the parameter passed to the max_inline mount option.
So we won't fail the mount if a junk value is specified, for example,
-o max_inline=abc. This patch checks if input is valid.
Signed-off-by: Anand Jain <anand.j...@oracle.com>
---
v2->v3: Handle parameter with unit, such as 4K. Use memparse() 2nd arg.
v1->v2: use match_int ret value if error
use %u instead of %d for parser
fs/btrfs/super.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 77e0537e1db5..76b58da8d56d 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -605,7 +605,14 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char
*options,
case Opt_max_inline:
num = match_strdup(&args[0]);
if (num) {
- info->max_inline = memparse(num, NULL);
+ char *retptr;
+
+ info->max_inline = memparse(num, &retptr);
I missed it in the patch that changed max_inline to u32, memparse
returns unsigned long long, so this is not entrely correct and requires
a temporary variable.
We should also report if the user-specified value is larger than
BTRFS_MAX_METADATA_BLOCKSIZE .
(Got diverted into something else. Sorry for the delay.)
Currently -o max_line can be only upto sectorsize.
We have MAX_INLINE_EXTENT_BUFFER_SIZE which is 64K and is equal to
BTRFS_MAX_METADATA_BLOCKSIZE (also 64K)
I didn't get the point that max_inline is limited by sector size in the
current design. Any idea?
Thanks, Anand
-------
#define BTRFS_MAX_METADATA_BLOCKSIZE 65536
#define INLINE_EXTENT_BUFFER_PAGES 16
#define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES *
PAGE_SIZE)
---------
static struct extent_buffer *
__alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start,
unsigned long len)
{
::
/*
* Sanity checks, currently the maximum is 64k covered by 16x 4k pages
*/
BUILD_BUG_ON(BTRFS_MAX_METADATA_BLOCKSIZE
> MAX_INLINE_EXTENT_BUFFER_SIZE);
BUG_ON(len > MAX_INLINE_EXTENT_BUFFER_SIZE);
-----
int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
unsigned long new_flags)
{
::
if (info->max_inline) {
info->max_inline = min_t(u64,
info->max_inline,
info->sectorsize);
}
-----
This is not a trivial fix the existing patches so I'll remove "btrfs:
declare max_inline as u32".
To sum it up:
1. add check and return EINVAL with a message if max_inline is larger
than the metadata block size
2. switch max_inline to u32 and add a temporary value to read from
memparse
3. add change from this patch that catches the junk
+ if (*retptr != '\0') {
+ ret = -EINVAL;
+ kfree(num);
The kfree can be moved before the check, we don't need 'num'.
+ goto out;
+ }
kfree(num);
if (info->max_inline) {
--
2.15.0
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
