Patch "erofs: fix illegal unmapped accesses in z_erofs_fill_inode_lazy()" has been added to the 6.0-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    erofs: fix illegal unmapped accesses in z_erofs_fill_inode_lazy()

to the 6.0-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     erofs-fix-illegal-unmapped-accesses-in-z_erofs_fill_.patch
and it can be found in the queue-6.0 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit b95b03c53efc1eccb1872b52e07549c5cebf4f76
Author: Yue Hu <huyue2@xxxxxxxxxxx>
Date:   Wed Oct 5 09:35:28 2022 +0800

    erofs: fix illegal unmapped accesses in z_erofs_fill_inode_lazy()
    
    [ Upstream commit 664609e49f1c84fc97987b2bf64544e586b8849c ]
    
    Note that we are still accessing 'h_idata_size' and 'h_fragmentoff'
    after calling erofs_put_metabuf(), that is not correct. Fix it.
    
    Fixes: ab92184ff8f1 ("erofs: add on-disk compressed tail-packing inline support")
    Fixes: b15b2e307c3a ("erofs: support on-disk compressed fragments data")
    Signed-off-by: Yue Hu <huyue2@xxxxxxxxxxx>
    Reviewed-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
    Reviewed-by: Chao Yu <chao@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20221005013528.62977-1-zbestahu@xxxxxxx
    Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index d58549ca1df9..63fd2f146026 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -61,8 +61,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 
 	pos = ALIGN(iloc(EROFS_SB(sb), vi->nid) + vi->inode_isize +
 		    vi->xattr_isize, 8);
-	kaddr = erofs_read_metabuf(&buf, sb, erofs_blknr(pos),
-				   EROFS_KMAP_ATOMIC);
+	kaddr = erofs_read_metabuf(&buf, sb, erofs_blknr(pos), EROFS_KMAP);
 	if (IS_ERR(kaddr)) {
 		err = PTR_ERR(kaddr);
 		goto out_unlock;
@@ -79,7 +78,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 		erofs_err(sb, "unknown HEAD%u format %u for nid %llu, please upgrade kernel",
 			  headnr + 1, vi->z_algorithmtype[headnr], vi->nid);
 		err = -EOPNOTSUPP;
-		goto unmap_done;
+		goto out_put_metabuf;
 	}
 
 	vi->z_logical_clusterbits = LOG_BLOCK_SIZE + (h->h_clusterbits & 7);
@@ -89,7 +88,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 		erofs_err(sb, "per-inode big pcluster without sb feature for nid %llu",
 			  vi->nid);
 		err = -EFSCORRUPTED;
-		goto unmap_done;
+		goto out_put_metabuf;
 	}
 	if (vi->datalayout == EROFS_INODE_FLAT_COMPRESSION &&
 	    !(vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1) ^
@@ -97,12 +96,8 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 		erofs_err(sb, "big pcluster head1/2 of compact indexes should be consistent for nid %llu",
 			  vi->nid);
 		err = -EFSCORRUPTED;
-		goto unmap_done;
+		goto out_put_metabuf;
 	}
-unmap_done:
-	erofs_put_metabuf(&buf);
-	if (err)
-		goto out_unlock;
 
 	if (vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER) {
 		struct erofs_map_blocks map = {
@@ -121,11 +116,13 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 			err = -EFSCORRUPTED;
 		}
 		if (err < 0)
-			goto out_unlock;
+			goto out_put_metabuf;
 	}
 	/* paired with smp_mb() at the beginning of the function */
 	smp_mb();
 	set_bit(EROFS_I_Z_INITED_BIT, &vi->flags);
+out_put_metabuf:
+	erofs_put_metabuf(&buf);
 out_unlock:
 	clear_and_wake_up_bit(EROFS_I_BL_Z_BIT, &vi->flags);
 	return err;