[PATCH] btrfs: initialize variable cancel

[PATCH] btrfs: initialize variable cancel

[trix]

From: Tom Rix <trix@redhat.com>

Clang static analysis reports this problem
ioctl.c:3333:8: warning: 3rd function call argument is an
  uninitialized value
    ret = exclop_start_or_cancel_reloc(fs_info,

cancel is only set in one branch of an if-check and is
always used.  So initialize to false.

Fixes: 1a15eb724aae ("btrfs: use btrfs_get_dev_args_from_path in dev removal ioctls")
Signed-off-by: Tom Rix <trix@redhat.com>
---
 fs/btrfs/ioctl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 190ad8af4f45a..26e82379747f8 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3308,7 +3308,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
 	struct block_device *bdev = NULL;
 	fmode_t mode;
 	int ret;
-	bool cancel;
+	bool cancel = false;
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-- 
2.26.3

Re: [PATCH] btrfs: initialize variable cancel

[Filipe Manana]

On Fri, Jan 21, 2022 at 05:45:22AM -0800, trix@redhat.com wrote:
> From: Tom Rix <trix@redhat.com>
> 
> Clang static analysis reports this problem
> ioctl.c:3333:8: warning: 3rd function call argument is an
>   uninitialized value
>     ret = exclop_start_or_cancel_reloc(fs_info,
> 
> cancel is only set in one branch of an if-check and is
> always used.  So initialize to false.
> 
> Fixes: 1a15eb724aae ("btrfs: use btrfs_get_dev_args_from_path in dev removal ioctls")
> Signed-off-by: Tom Rix <trix@redhat.com>

Reviewed-by: Filipe Manana <fdmanana@suse.com>

Could use a more precise subject like for example:

  "btrfs: fix use of uninitialized variable at rm device ioctl"

Anyway, it looks good.
Thanks.

> ---
>  fs/btrfs/ioctl.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index 190ad8af4f45a..26e82379747f8 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -3308,7 +3308,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
>  	struct block_device *bdev = NULL;
>  	fmode_t mode;
>  	int ret;
> -	bool cancel;
> +	bool cancel = false;
>  
>  	if (!capable(CAP_SYS_ADMIN))
>  		return -EPERM;
> -- 
> 2.26.3
> 

Re: [PATCH] btrfs: initialize variable cancel

[Anand Jain]

On 21/01/2022 21:45, trix@redhat.com wrote:
> From: Tom Rix <trix@redhat.com>
> 
> Clang static analysis reports this problem
> ioctl.c:3333:8: warning: 3rd function call argument is an
>    uninitialized value
>      ret = exclop_start_or_cancel_reloc(fs_info,
> 
> cancel is only set in one branch of an if-check and is
> always used.  So initialize to false.
> 
> Fixes: 1a15eb724aae ("btrfs: use btrfs_get_dev_args_from_path in dev removal ioctls")
> Signed-off-by: Tom Rix <trix@redhat.com>
> ---
>   fs/btrfs/ioctl.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index 190ad8af4f45a..26e82379747f8 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -3308,7 +3308,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
>   	struct block_device *bdev = NULL;
>   	fmode_t mode;
>   	int ret;
> -	bool cancel;
> +	bool cancel = false;


  Reviewed-by: Anand Jain <anand.jain@oracle.com>

Thanks,
Anand

>   
>   	if (!capable(CAP_SYS_ADMIN))
>   		return -EPERM;

Re: [PATCH] btrfs: initialize variable cancel

[David Sterba]

On Fri, Jan 21, 2022 at 05:45:22AM -0800, trix@redhat.com wrote:
> From: Tom Rix <trix@redhat.com>
> 
> Clang static analysis reports this problem
> ioctl.c:3333:8: warning: 3rd function call argument is an
>   uninitialized value
>     ret = exclop_start_or_cancel_reloc(fs_info,
> 
> cancel is only set in one branch of an if-check and is
> always used.  So initialize to false.
> 
> Fixes: 1a15eb724aae ("btrfs: use btrfs_get_dev_args_from_path in dev removal ioctls")
> Signed-off-by: Tom Rix <trix@redhat.com>

Added to misc-next, with the updted subject line, thanks.