Re: [PATCH] squashfs: Avoid mem leak in squashfs_fill_super

[Scott Guo <scott_gzh@163.com>]

在 2025/8/12 6:35, Phillip Lougher 写道:
> 
> 
> On 11/08/2025 07:19, scott_gzh@163.com wrote:
>> From: Scott GUO <scottzhguo@tencent.com>
>>
>> If sb_min_blocksize returns 0, -EINVAL was returned without freeing
>> sb->s_fs_info, causing mem leak.
>>
>> Fix it by goto failed_mount.
>>
> 
> Thanks for spotting this, but, NACK to the patch.
> 
> A better fix is to call sb_min_blocksize and check the
> return result before the memory is allocated.
OK, will send v2.>
> Phillip
> 
>> Fixes: 734aa85390ea ("Squashfs: check return result of sb_min_blocksize")
>> Signed-off-by: Scott GUO <scottzhguo@tencent.com>
>> ---
>>   fs/squashfs/super.c | 6 +++---
>>   1 file changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
>> index 992ea0e37257..7d501083b2e3 100644
>> --- a/fs/squashfs/super.c
>> +++ b/fs/squashfs/super.c
>> @@ -201,10 +201,12 @@ static int squashfs_fill_super(struct 
>> super_block *sb, struct fs_context *fc)
>>       msblk->panic_on_errors = (opts->errors == Opt_errors_panic);
>> +    err = -EINVAL;
>> +
>>       msblk->devblksize = sb_min_blocksize(sb, SQUASHFS_DEVBLK_SIZE);
>>       if (!msblk->devblksize) {
>>           errorf(fc, "squashfs: unable to set blocksize\n");
>> -        return -EINVAL;
>> +        goto failed_mount;
>>       }
>>       msblk->devblksize_log2 = ffz(~msblk->devblksize);
>> @@ -227,8 +229,6 @@ static int squashfs_fill_super(struct super_block 
>> *sb, struct fs_context *fc)
>>           goto failed_mount;
>>       }
>> -    err = -EINVAL;
>> -
>>       /* Check it is a SQUASHFS superblock */
>>       sb->s_magic = le32_to_cpu(sblk->s_magic);
>>       if (sb->s_magic != SQUASHFS_MAGIC) {