ext2fs_free() does not set the ext2_filsys pointer to null so the caller
is responsible to setting it himself if it is needed.
This patch fixes some places where caller did not set ext2_filsys
pointer to NULL after ext2fs_free() which might result in use after
free. Fix it.
Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx>
---
lib/ext2fs/openfs.c | 7 ++++---
resize/resize2fs.c | 5 ++++-
2 files changed, 8 insertions(+), 4 deletions(-)
diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c
index aba8a50..b4122de 100644
--- a/lib/ext2fs/openfs.c
+++ b/lib/ext2fs/openfs.c
@@ -476,10 +476,11 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
return 0;
cleanup:
- if (flags & EXT2_FLAG_NOFREE_ON_ERROR)
- *ret_fs = fs;
- else
+ if (!(flags & EXT2_FLAG_NOFREE_ON_ERROR)) {
ext2fs_free(fs);
+ fs = NULL;
+ }
+ *ret_fs = fs;
return retval;
}
diff --git a/resize/resize2fs.c b/resize/resize2fs.c
index 498cf99..8353338 100644
--- a/resize/resize2fs.c
+++ b/resize/resize2fs.c
@@ -209,6 +209,7 @@ errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
rfs->flags = flags;
ext2fs_free(rfs->old_fs);
+ rfs->old_fs = NULL;
if (rfs->itable_buf)
ext2fs_free_mem(&rfs->itable_buf);
if (rfs->reserve_blocks)
@@ -220,8 +221,10 @@ errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
return 0;
errout:
- if (rfs->new_fs)
+ if (rfs->new_fs) {
ext2fs_free(rfs->new_fs);
+ rfs->new_fs = NULL;
+ }
if (rfs->itable_buf)
ext2fs_free_mem(&rfs->itable_buf);
ext2fs_free_mem(&rfs);
--
1.8.3.1
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