lkml.org 
[lkml]   [2018]   [Jul]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH] nfsd: fix memory leak of async_copy
Date
On 17/07/18 10:30, Dan Carpenter wrote:
> On Mon, Jul 16, 2018 at 01:09:54PM +0100, Colin King wrote:
>> From: Colin Ian King <colin.king@canonical.com>
>>
>> In the case where async_copy is successfully allocated but
>> the call to nfs4_init_cp_state fails, async_copy is not
>> currently freed and the memory is leaked. Fix this by kfree'ing
>> it before returning.
>>
>> Detected by CoverityScan, CID#1471823 ("Resource leak")
>>
>> Fixes: beb1814d5a8a ("NFSD create new stateid for async copy")
>> Signed-off-by: Colin Ian King <colin.king@canonical.com>
>> ---
>> fs/nfsd/nfs4proc.c | 4 +++-
>> 1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
>> index 8f3368353aaf..3fb96a2708b9 100644
>> --- a/fs/nfsd/nfs4proc.c
>> +++ b/fs/nfsd/nfs4proc.c
>> @@ -1295,8 +1295,10 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>> async_copy = kzalloc(sizeof(struct nfsd4_copy), GFP_KERNEL);
>> if (!async_copy)
>> goto out;
>> - if (!nfs4_init_cp_state(nn, copy))
>> + if (!nfs4_init_cp_state(nn, copy)) {
>> + kfree(async_copy);
>> goto out;
>
> It really feels like both this and the kzalloc() failure should be doing
> an of fput() of copy->file_src and copy->file_dst. The goto out_err
> does an list_del(&copy->copies); but it happens before the
> "list_add(&async_copy->copies ..." so that's likely wrong as well.

Good observation, thanks for spotting that. I suspect I'm a bit out of
my depth figuring out the exact error handling reaping steps here.
Perhaps this is one for the maintainers to figure out a safe cleanup on
these error paths.

>
> regards,
> dan carpenter
>
> --
> To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>

\
 
 \ /
  Last update: 2018-07-17 11:35    [W:0.123 / U:0.616 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site