[PATCH] erofs: fix the unmapped access in z_erofs_fill_inode_lazy()

From: Yue Hu
Date: Tue Oct 04 2022 - 10:50:46 EST


From: Yue Hu <huyue2@xxxxxxxxxxx>

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 ("add on-disk compressed tail-packing inline support")
Fixes: b15b2e307c3a ("support on-disk compressed fragments data")
Signed-off-by: Yue Hu <huyue2@xxxxxxxxxxx>
---
fs/erofs/zmap.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index 44c27ef39c43..1a15bbf18ba3 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -58,7 +58,7 @@ 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);
+ EROFS_KMAP);
if (IS_ERR(kaddr)) {
err = PTR_ERR(kaddr);
goto out_unlock;
@@ -73,7 +73,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
vi->z_advise = Z_EROFS_ADVISE_FRAGMENT_PCLUSTER;
vi->z_fragmentoff = le64_to_cpu(*(__le64 *)h) ^ (1ULL << 63);
vi->z_tailextent_headlcn = 0;
- goto unmap_done;
+ goto init_done;
}
vi->z_advise = le16_to_cpu(h->h_advise);
vi->z_algorithmtype[0] = h->h_algorithmtype & 15;
@@ -105,10 +105,6 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
err = -EFSCORRUPTED;
goto unmap_done;
}
-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 = {
@@ -127,7 +123,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
err = -EFSCORRUPTED;
}
if (err < 0)
- goto out_unlock;
+ goto unmap_done;
}

if (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER &&
@@ -141,11 +137,14 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
EROFS_GET_BLOCKS_FINDTAIL);
erofs_put_metabuf(&map.buf);
if (err < 0)
- goto out_unlock;
+ goto unmap_done;
}
+init_done:
/* paired with smp_mb() at the beginning of the function */
smp_mb();
set_bit(EROFS_I_Z_INITED_BIT, &vi->flags);
+unmap_done:
+ erofs_put_metabuf(&buf);
out_unlock:
clear_and_wake_up_bit(EROFS_I_BL_Z_BIT, &vi->flags);
return err;
--
2.25.1