[patch 10/19] mm, slub: fix two bugs in slab_debug_trace_open()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Subject: mm, slub: fix two bugs in slab_debug_trace_open()

Patch series "Fixups for slub".

This series contains various bug fixes for slub.  We fix memoryleak,
use-afer-free, NULL pointer dereferencing and so on in slub.  More details
can be found in the respective changelogs.


This patch (of 5):

It's possible that __seq_open_private() will return NULL.  So we should
check it before using lest dereferencing NULL pointer.  And in error
paths, we forgot to release private buffer via seq_release_private(). 
Memory will leak in these paths.

Link: https://lkml.kernel.org/r/20210916123920.48704-1-linmiaohe@xxxxxxxxxx
Link: https://lkml.kernel.org/r/20210916123920.48704-2-linmiaohe@xxxxxxxxxx
Fixes: 64dd68497be7 ("mm: slub: move sysfs slab alloc/free interfaces to debugfs")
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Faiyaz Mohammed <faiyazm@xxxxxxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Bharata B Rao <bharata@xxxxxxxxxxxxx>
Cc: Roman Gushchin <guro@xxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 mm/slub.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/mm/slub.c~mm-slub-fix-two-bugs-in-slab_debug_trace_open
+++ a/mm/slub.c
@@ -6108,9 +6108,14 @@ static int slab_debug_trace_open(struct
 	struct kmem_cache *s = file_inode(filep)->i_private;
 	unsigned long *obj_map;
 
+	if (!t)
+		return -ENOMEM;
+
 	obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL);
-	if (!obj_map)
+	if (!obj_map) {
+		seq_release_private(inode, filep);
 		return -ENOMEM;
+	}
 
 	if (strcmp(filep->f_path.dentry->d_name.name, "alloc_traces") == 0)
 		alloc = TRACK_ALLOC;
@@ -6119,6 +6124,7 @@ static int slab_debug_trace_open(struct
 
 	if (!alloc_loc_track(t, PAGE_SIZE / sizeof(struct location), GFP_KERNEL)) {
 		bitmap_free(obj_map);
+		seq_release_private(inode, filep);
 		return -ENOMEM;
 	}
 
_



[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux