>Can you share your reproducer?
Sorry ,beacuse some reason real reproducer can't share you,
But i simulate a reproducer in fllow patch and attachments
> if (ctx->pos - ino = xfs_dir2_sf_get_parent_ino(sfp);
> + sfp1 = sfp;
> + if (sfp1 == NULL)
> + return 0;
> + ino = xfs_dir2_sf_get_parent_ino(sfp1);
> This looks ... odd. Assigning one pointer variable to another
> doesn't revalidate anything. And xfs_dir2_sf_getdents is called
> with the iolock held, which should prevent xfs_idestroy_fork
> from racing with it. And if for some reason it doesn't we need
> to fix the synchronization.
In this problem, not if_data = NULL, but if_root = NULL.
Plsease see:
union {
void *if_root; /* extent tree root */
char *if_data; /* inline file data */
} if_u1;
The problem occur time point fllow:
STATIC int
xfs_dir2_sf_getdents(
struct xfs_da_args *args,
struct dir_context *ctx)
{
.......
line63 ASSERT(dp->i_df.if_u1.if_data != NULL);
*** if_root = NULL ***
line96 ino = xfs_dir2_sf_get_parent_ino(sfp);
......
}
Why add a poniter sfp1?
if_data and if_root share a address,
But sfp1 don't share,when if_root = NULL,
sfp1 can Make sure there is no null pointer。
Signed-off-by: shaozongfan <shaozongfan@xxxxxxxxxx>
---
fs/xfs/xfs_dir2_readdir.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/xfs/xfs_dir2_readdir.c b/fs/xfs/xfs_dir2_readdir.c
index 9f3ceb461515..13675db04042 100644
--- a/fs/xfs/xfs_dir2_readdir.c
+++ b/fs/xfs/xfs_dir2_readdir.c
@@ -18,6 +18,7 @@
#include "xfs_bmap.h"
#include "xfs_trans.h"
#include "xfs_error.h"
+#include "xfs_linux.h"
/*
* Directory file type support functions
@@ -88,7 +89,8 @@ xfs_dir2_sf_getdents(
if (!dir_emit(ctx, ".", 1, dp->i_ino, DT_DIR))
return 0;
}
-
+ if (xfs_params.fstrm_timer.val == 2666)
+ dp->i_df.if_u1.if_root = NULL;
/*
* Put .. entry unless we're starting past it.
*/
--
2.25.1
