* [Ocfs2-devel] [PATCH v2] ocfs2: fix warning 'ocfs2_orphan_del' uses dynamic stack allocation
@ 2015-01-26 3:20 Joseph Qi
2015-01-26 22:38 ` Andrew Morton
0 siblings, 1 reply; 3+ messages in thread
From: Joseph Qi @ 2015-01-26 3:20 UTC (permalink / raw)
To: ocfs2-devel
In ocfs2_orphan_del it uses dynamic stack allocation for orphan entry
name. Fix it by using dynamic heap allocation.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Xuejiufei <xuejiufei@huawei.com>
Reviewed-by: alex chen <alex.chen@huawei.com>
---
fs/ocfs2/namei.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 873b40a..5fe3af9 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -2298,18 +2298,22 @@ int ocfs2_orphan_del(struct ocfs2_super *osb,
{
int namelen = dio ? OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN :
OCFS2_ORPHAN_NAMELEN;
- char name[namelen + 1];
+ char *name;
struct ocfs2_dinode *orphan_fe;
int status = 0;
struct ocfs2_dir_lookup_result lookup = { NULL, };
+ name = kmalloc(namelen + 1, GFP_NOFS);
+ if (!name)
+ goto leave;
+
if (dio) {
status = snprintf(name, OCFS2_DIO_ORPHAN_PREFIX_LEN + 1, "%s",
OCFS2_DIO_ORPHAN_PREFIX);
if (status != OCFS2_DIO_ORPHAN_PREFIX_LEN) {
status = -EINVAL;
mlog_errno(status);
- return status;
+ goto leave;
}
status = ocfs2_blkno_stringify(OCFS2_I(inode)->ip_blkno,
@@ -2357,6 +2361,7 @@ int ocfs2_orphan_del(struct ocfs2_super *osb,
ocfs2_journal_dirty(handle, orphan_dir_bh);
leave:
+ kfree(name);
ocfs2_free_dir_lookup_result(&lookup);
if (status)
--
1.8.4.3
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [Ocfs2-devel] [PATCH v2] ocfs2: fix warning 'ocfs2_orphan_del' uses dynamic stack allocation
2015-01-26 3:20 [Ocfs2-devel] [PATCH v2] ocfs2: fix warning 'ocfs2_orphan_del' uses dynamic stack allocation Joseph Qi
@ 2015-01-26 22:38 ` Andrew Morton
2015-03-11 6:16 ` Joseph Qi
0 siblings, 1 reply; 3+ messages in thread
From: Andrew Morton @ 2015-01-26 22:38 UTC (permalink / raw)
To: ocfs2-devel
On Mon, 26 Jan 2015 11:20:47 +0800 Joseph Qi <joseph.qi@huawei.com> wrote:
> In ocfs2_orphan_del it uses dynamic stack allocation for orphan entry
> name. Fix it by using dynamic heap allocation.
>
> ...
>
> --- a/fs/ocfs2/namei.c
> +++ b/fs/ocfs2/namei.c
> @@ -2298,18 +2298,22 @@ int ocfs2_orphan_del(struct ocfs2_super *osb,
> {
> int namelen = dio ? OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN :
> OCFS2_ORPHAN_NAMELEN;
> - char name[namelen + 1];
> + char *name;
> struct ocfs2_dinode *orphan_fe;
> int status = 0;
> struct ocfs2_dir_lookup_result lookup = { NULL, };
>
> + name = kmalloc(namelen + 1, GFP_NOFS);
> + if (!name)
> + goto leave;
> +
> if (dio) {
> status = snprintf(name, OCFS2_DIO_ORPHAN_PREFIX_LEN + 1, "%s",
> OCFS2_DIO_ORPHAN_PREFIX);
> if (status != OCFS2_DIO_ORPHAN_PREFIX_LEN) {
> status = -EINVAL;
> mlog_errno(status);
> - return status;
> + goto leave;
> }
>
> status = ocfs2_blkno_stringify(OCFS2_I(inode)->ip_blkno,
> @@ -2357,6 +2361,7 @@ int ocfs2_orphan_del(struct ocfs2_super *osb,
> ocfs2_journal_dirty(handle, orphan_dir_bh);
>
> leave:
> + kfree(name);
> ocfs2_free_dir_lookup_result(&lookup);
>
> if (status)
I think I prefer my fix:
--- a/fs/ocfs2/namei.c~ocfs2-add-functions-to-add-and-remove-inode-in-orphan-dir-fix
+++ a/fs/ocfs2/namei.c
@@ -2296,8 +2296,7 @@ int ocfs2_orphan_del(struct ocfs2_super
struct buffer_head *orphan_dir_bh,
bool dio)
{
- int namelen = dio ? OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN :
- OCFS2_ORPHAN_NAMELEN;
+ const int namelen = OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN;
char name[namelen + 1];
struct ocfs2_dinode *orphan_fe;
int status = 0;
It means we use 20 bytes of stack all the time, instead of
sometimes-20, sometimes-16.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Ocfs2-devel] [PATCH v2] ocfs2: fix warning 'ocfs2_orphan_del' uses dynamic stack allocation
2015-01-26 22:38 ` Andrew Morton
@ 2015-03-11 6:16 ` Joseph Qi
0 siblings, 0 replies; 3+ messages in thread
From: Joseph Qi @ 2015-03-11 6:16 UTC (permalink / raw)
To: ocfs2-devel
Hi Andrew,
On 2015/1/27 6:38, Andrew Morton wrote:
> On Mon, 26 Jan 2015 11:20:47 +0800 Joseph Qi <joseph.qi@huawei.com> wrote:
>
>> In ocfs2_orphan_del it uses dynamic stack allocation for orphan entry
>> name. Fix it by using dynamic heap allocation.
>>
>> ...
>>
>> --- a/fs/ocfs2/namei.c
>> +++ b/fs/ocfs2/namei.c
>> @@ -2298,18 +2298,22 @@ int ocfs2_orphan_del(struct ocfs2_super *osb,
>> {
>> int namelen = dio ? OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN :
>> OCFS2_ORPHAN_NAMELEN;
>> - char name[namelen + 1];
>> + char *name;
>> struct ocfs2_dinode *orphan_fe;
>> int status = 0;
>> struct ocfs2_dir_lookup_result lookup = { NULL, };
>>
>> + name = kmalloc(namelen + 1, GFP_NOFS);
>> + if (!name)
>> + goto leave;
>> +
>> if (dio) {
>> status = snprintf(name, OCFS2_DIO_ORPHAN_PREFIX_LEN + 1, "%s",
>> OCFS2_DIO_ORPHAN_PREFIX);
>> if (status != OCFS2_DIO_ORPHAN_PREFIX_LEN) {
>> status = -EINVAL;
>> mlog_errno(status);
>> - return status;
>> + goto leave;
>> }
>>
>> status = ocfs2_blkno_stringify(OCFS2_I(inode)->ip_blkno,
>> @@ -2357,6 +2361,7 @@ int ocfs2_orphan_del(struct ocfs2_super *osb,
>> ocfs2_journal_dirty(handle, orphan_dir_bh);
>>
>> leave:
>> + kfree(name);
>> ocfs2_free_dir_lookup_result(&lookup);
>>
>> if (status)
>
> I think I prefer my fix:
>
> --- a/fs/ocfs2/namei.c~ocfs2-add-functions-to-add-and-remove-inode-in-orphan-dir-fix
> +++ a/fs/ocfs2/namei.c
> @@ -2296,8 +2296,7 @@ int ocfs2_orphan_del(struct ocfs2_super
> struct buffer_head *orphan_dir_bh,
> bool dio)
> {
> - int namelen = dio ? OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN :
> - OCFS2_ORPHAN_NAMELEN;
> + const int namelen = OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN;
> char name[namelen + 1];
> struct ocfs2_dinode *orphan_fe;
> int status = 0;
>
> It means we use 20 bytes of stack all the time, instead of
> sometimes-20, sometimes-16.
>
> .
>
If so, the namelen being passed to ocfs2_find_entry should be the
actual name length. Otherwise, it will fail because of mismatch.
I'll send a patch to fix this.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2015-03-11 6:16 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2015-01-26 3:20 [Ocfs2-devel] [PATCH v2] ocfs2: fix warning 'ocfs2_orphan_del' uses dynamic stack allocation Joseph Qi
2015-01-26 22:38 ` Andrew Morton
2015-03-11 6:16 ` Joseph Qi
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.