2020-04-21 12:50:28

by Colin King

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Subject: [PATCH][next] btrfs: fix check for memory allocation failure of ret->path

From: Colin Ian King <[email protected]>

Currently the memory allocation failure check for ret->path is checking
that ret is null rather than ret->path. Fix this by checking ret->path
instead.

Addresses-Coverity: ("Dereference null return")
Fixes: bd8bdc532152 ("btrfs: backref: introduce the skeleton of btrfs_backref_iter")
Signed-off-by: Colin Ian King <[email protected]>
---
fs/btrfs/backref.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 60a69f7c0b36..78e6c9a64212 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -2307,7 +2307,7 @@ struct btrfs_backref_iter *btrfs_backref_iter_alloc(
return NULL;

ret->path = btrfs_alloc_path();
- if (!ret) {
+ if (!ret->path) {
kfree(ret);
return NULL;
}
--
2.25.1


2020-04-21 12:52:05

by Qu Wenruo

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Subject: Re: [PATCH][next] btrfs: fix check for memory allocation failure of ret->path



On 2020/4/21 下午8:47, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> Currently the memory allocation failure check for ret->path is checking
> that ret is null rather than ret->path. Fix this by checking ret->path
> instead.
>
> Addresses-Coverity: ("Dereference null return")
> Fixes: bd8bdc532152 ("btrfs: backref: introduce the skeleton of btrfs_backref_iter")
> Signed-off-by: Colin Ian King <[email protected]>

My bad.

Reviewed-by: Qu Wenruo <[email protected]>

Thanks,
Qu
> ---
> fs/btrfs/backref.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
> index 60a69f7c0b36..78e6c9a64212 100644
> --- a/fs/btrfs/backref.c
> +++ b/fs/btrfs/backref.c
> @@ -2307,7 +2307,7 @@ struct btrfs_backref_iter *btrfs_backref_iter_alloc(
> return NULL;
>
> ret->path = btrfs_alloc_path();
> - if (!ret) {
> + if (!ret->path) {
> kfree(ret);
> return NULL;
> }
>

2020-04-27 15:22:52

by David Sterba

[permalink] [raw]
Subject: Re: [PATCH][next] btrfs: fix check for memory allocation failure of ret->path

On Tue, Apr 21, 2020 at 01:47:03PM +0100, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> Currently the memory allocation failure check for ret->path is checking
> that ret is null rather than ret->path. Fix this by checking ret->path
> instead.
>
> Addresses-Coverity: ("Dereference null return")
> Fixes: bd8bdc532152 ("btrfs: backref: introduce the skeleton of btrfs_backref_iter")

As this is still in development branch, fixup folded in. Thanks.