This fix the oops in ext4 unit test which is cuased by NULL sb.s_user_ns as following: <4>[ 14.344565] map_id_range_down (kernel/user_namespace.c:318) <4>[ 14.345378] make_kuid (kernel/user_namespace.c:415) <4>[ 14.345998] inode_init_always (include/linux/fs.h:1375 fs/inode.c:174) <4>[ 14.346696] alloc_inode (fs/inode.c:268) <4>[ 14.347353] new_inode_pseudo (fs/inode.c:1007) <4>[ 14.348016] new_inode (fs/inode.c:1033) <4>[ 14.348644] ext4_mb_init (fs/ext4/mballoc.c:3404 fs/ext4/mballoc.c:3719) <4>[ 14.349312] mbt_kunit_init (fs/ext4/mballoc-test.c:57 fs/ext4/mballoc-test.c:314) <4>[ 14.349983] kunit_try_run_case (lib/kunit/test.c:388 lib/kunit/test.c:443) <4>[ 14.350696] kunit_generic_run_threadfn_adapter (lib/kunit/try-catch.c:30) <4>[ 14.351530] kthread (kernel/kthread.c:388) <4>[ 14.352168] ret_from_fork (arch/arm64/kernel/entry.S:861) <0>[ 14.353385] Code: 52808004 b8236ae7 72be5e44 b90004c4 (38e368a1) Alloc test super block from sget to properly initialize test super block to fix the issue. Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx> Reported-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- fs/ext4/mballoc-test.c | 46 ++++++++++++++++++++++++++++-------------- 1 file changed, 31 insertions(+), 15 deletions(-) diff --git a/fs/ext4/mballoc-test.c b/fs/ext4/mballoc-test.c index 12d0b22cabe1..1da52bbf4599 100644 --- a/fs/ext4/mballoc-test.c +++ b/fs/ext4/mballoc-test.c @@ -21,16 +21,27 @@ struct mbt_ctx { }; struct mbt_ext4_super_block { - struct super_block sb; + struct ext4_super_block es; + struct ext4_sb_info sbi; struct mbt_ctx mbt_ctx; }; -#define MBT_CTX(_sb) (&(container_of((_sb), struct mbt_ext4_super_block, sb)->mbt_ctx)) +#define MBT_SB(_sb) (container_of((_sb)->s_fs_info, struct mbt_ext4_super_block, sbi)) +#define MBT_CTX(_sb) (&MBT_SB(_sb)->mbt_ctx) #define MBT_GRP_CTX(_sb, _group) (&MBT_CTX(_sb)->grp_ctx[_group]) static const struct super_operations mbt_sops = { }; +static void mbt_kill_sb(struct super_block *sb) +{ +} + +static struct file_system_type mbt_fs_type = { + .name = "mballoc test", + .kill_sb = mbt_kill_sb, +}; + static int mbt_mb_init(struct super_block *sb) { int ret; @@ -72,43 +83,48 @@ static void mbt_mb_release(struct super_block *sb) kfree(sb->s_bdev); } +static int mbt_set(struct super_block *sb, void *data) +{ + return 0; +} + static struct super_block *mbt_ext4_alloc_super_block(void) { - struct ext4_super_block *es = kzalloc(sizeof(*es), GFP_KERNEL); - struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); struct mbt_ext4_super_block *fsb = kzalloc(sizeof(*fsb), GFP_KERNEL); + struct super_block *sb = sget(&mbt_fs_type, NULL, mbt_set, 0, NULL); + struct ext4_sb_info *sbi; - if (fsb == NULL || sbi == NULL || es == NULL) + if (fsb == NULL || sb == NULL) goto out; + sbi = &fsb->sbi; + sbi->s_blockgroup_lock = kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); if (!sbi->s_blockgroup_lock) - goto out; + goto out_deactivate; bgl_lock_init(sbi->s_blockgroup_lock); - sbi->s_es = es; - fsb->sb.s_fs_info = sbi; + sbi->s_es = &fsb->es; + sb->s_fs_info = sbi; - return &fsb->sb; + return sb; +out_deactivate: + deactivate_locked_super(sb); out: kfree(fsb); - kfree(sbi); - kfree(es); return NULL; } static void mbt_ext4_free_super_block(struct super_block *sb) { - struct mbt_ext4_super_block *fsb = - container_of(sb, struct mbt_ext4_super_block, sb); + struct mbt_ext4_super_block *fsb = MBT_SB(sb); struct ext4_sb_info *sbi = EXT4_SB(sb); kfree(sbi->s_blockgroup_lock); - kfree(sbi->s_es); - kfree(sbi); + deactivate_locked_super(sb); kfree(fsb); } -- 2.30.0