[Cluster-devel] memory leak in gfs2_init_fs_context

[Cluster-devel] memory leak in gfs2_init_fs_context

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    f1f2f614 Merge branch 'next-integrity' of git://git.kernel..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15569c05600000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4e93436f92b0cfde
dashboard link: https://syzkaller.appspot.com/bug?extid=c2fdfd2b783754878fb6
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10327c05600000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=105c9fd5600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c2fdfd2b783754878fb6 at syzkaller.appspotmail.com

udit: type=1400 audit(1569701659.045:64): avc:  denied  { map } for   
pid=6842 comm="syz-executor375" path="/root/syz-executor375626622"  
dev="sda1" ino=16502 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023  
tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
executing program
executing program
BUG: memory leak
unreferenced object 0xffff88810fd9a500 (size 256):
   comm "syz-executor375", pid 6845, jiffies 4294941255 (age 13.550s)
   hex dump (first 32 bytes):
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
   backtrace:
     [<00000000462ab467>] kmemleak_alloc_recursive  
include/linux/kmemleak.h:43 [inline]
     [<00000000462ab467>] slab_post_alloc_hook mm/slab.h:586 [inline]
     [<00000000462ab467>] slab_alloc mm/slab.c:3319 [inline]
     [<00000000462ab467>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548
     [<00000000b1a62211>] kmalloc include/linux/slab.h:552 [inline]
     [<00000000b1a62211>] kzalloc include/linux/slab.h:686 [inline]
     [<00000000b1a62211>] gfs2_init_fs_context+0x25/0x90  
fs/gfs2/ops_fstype.c:1543
     [<00000000db94ecb4>] gfs2_meta_init_fs_context+0x17/0x40  
fs/gfs2/ops_fstype.c:1608
     [<0000000077df5577>] alloc_fs_context+0x174/0x200 fs/fs_context.c:293
     [<000000008d5e3681>] fs_context_for_mount+0x25/0x30 fs/fs_context.c:307
     [<0000000030bafbdb>] __do_sys_fsopen fs/fsopen.c:137 [inline]
     [<0000000030bafbdb>] __se_sys_fsopen fs/fsopen.c:115 [inline]
     [<0000000030bafbdb>] __x64_sys_fsopen+0xa9/0x1a0 fs/fsopen.c:115
     [<00000000974fed69>] do_syscall_64+0x73/0x1f0  
arch/x86/entry/common.c:290
     [<00000000299e0e1b>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: memory leak
unreferenced object 0xffff88810fd9a200 (size 256):
   comm "syz-executor375", pid 6846, jiffies 4294941838 (age 7.720s)
   hex dump (first 32 bytes):
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
   backtrace:
     [<00000000462ab467>] kmemleak_alloc_recursive  
include/linux/kmemleak.h:43 [inline]
     [<00000000462ab467>] slab_post_alloc_hook mm/slab.h:586 [inline]
     [<00000000462ab467>] slab_alloc mm/slab.c:3319 [inline]
     [<00000000462ab467>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548
     [<00000000b1a62211>] kmalloc include/linux/slab.h:552 [inline]
     [<00000000b1a62211>] kzalloc include/linux/slab.h:686 [inline]
     [<00000000b1a62211>] gfs2_init_fs_context+0x25/0x90  
fs/gfs2/ops_fstype.c:1543
     [<00000000db94ecb4>] gfs2_meta_init_fs_context+0x17/0x40  
fs/gfs2/ops_fstype.c:1608
     [<0000000077df5577>] alloc_fs_context+0x174/0x200 fs/fs_context.c:293
     [<000000008d5e3681>] fs_context_for_mount+0x25/0x30 fs/fs_context.c:307
     [<0000000030bafbdb>] __do_sys_fsopen fs/fsopen.c:137 [inline]
     [<0000000030bafbdb>] __se_sys_fsopen fs/fsopen.c:115 [inline]
     [<0000000030bafbdb>] __x64_sys_fsopen+0xa9/0x1a0 fs/fsopen.c:115
     [<00000000974fed69>] do_syscall_64+0x73/0x1f0  
arch/x86/entry/common.c:290
     [<00000000299e0e1b>] entry_SYSCALL_64_after_hwframe+0x44/0xa9



---
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[Cluster-devel] [PATCH] gfs2: Fix memory leak when gfs2meta's fs_context is freed

[Andrew Price]

gfs2 and gfs2meta share an ->init_fs_context function which allocates an
args structure stored in fc->fs_private. gfs2 registers a ->free
function to free this memory when the fs_context is cleaned up, but
there was not one registered for gfs2meta, causing a leak.

Register a ->free function for gfs2meta. The existing gfs2_fc_free
function does what we need.

Reported-by: syzbot+c2fdfd2b783754878fb6 at syzkaller.appspotmail.com
Signed-off-by: Andrew Price <anprice@redhat.com>
---
 fs/gfs2/ops_fstype.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 681b44682b0d..dc61af2c4d5e 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -1600,6 +1600,7 @@ static int gfs2_meta_get_tree(struct fs_context *fc)
 }
 
 static const struct fs_context_operations gfs2_meta_context_ops = {
+	.free        = gfs2_fc_free,
 	.get_tree    = gfs2_meta_get_tree,
 };
 
-- 
2.21.0

[Cluster-devel] [PATCH] gfs2: Fix memory leak when gfs2meta's fs_context is freed

[Bob Peterson]

----- Original Message -----
> gfs2 and gfs2meta share an ->init_fs_context function which allocates an
> args structure stored in fc->fs_private. gfs2 registers a ->free
> function to free this memory when the fs_context is cleaned up, but
> there was not one registered for gfs2meta, causing a leak.
> 
> Register a ->free function for gfs2meta. The existing gfs2_fc_free
> function does what we need.
> 
> Reported-by: syzbot+c2fdfd2b783754878fb6 at syzkaller.appspotmail.com
> Signed-off-by: Andrew Price <anprice@redhat.com>
> ---

Thanks. Now pushed to for-next.

Bob Peterson

[Cluster-devel] [PATCH] gfs2: Fix memory leak when gfs2meta's fs_context is freed

[Andrew Price]

On 04/10/2019 18:20, Bob Peterson wrote:
> ----- Original Message -----
>> gfs2 and gfs2meta share an ->init_fs_context function which allocates an
>> args structure stored in fc->fs_private. gfs2 registers a ->free
>> function to free this memory when the fs_context is cleaned up, but
>> there was not one registered for gfs2meta, causing a leak.
>>
>> Register a ->free function for gfs2meta. The existing gfs2_fc_free
>> function does what we need.
>>
>> Reported-by: syzbot+c2fdfd2b783754878fb6 at syzkaller.appspotmail.com
>> Signed-off-by: Andrew Price <anprice@redhat.com>
>> ---
> 
> Thanks. Now pushed to for-next.

Thanks Bob. Can we get this sent to Linus as a fix during this cycle?

Andy

[Cluster-devel] [PATCH] gfs2: Fix memory leak when gfs2meta's fs_context is freed

[Andrew Price]

On 09/10/2019 07:36, Andrew Price wrote:
> On 04/10/2019 18:20, Bob Peterson wrote:
>> ----- Original Message -----
>>> gfs2 and gfs2meta share an ->init_fs_context function which allocates an
>>> args structure stored in fc->fs_private. gfs2 registers a ->free
>>> function to free this memory when the fs_context is cleaned up, but
>>> there was not one registered for gfs2meta, causing a leak.
>>>
>>> Register a ->free function for gfs2meta. The existing gfs2_fc_free
>>> function does what we need.
>>>
>>> Reported-by: syzbot+c2fdfd2b783754878fb6 at syzkaller.appspotmail.com
>>> Signed-off-by: Andrew Price <anprice@redhat.com>
>>> ---
>>
>> Thanks. Now pushed to for-next.
> 
> Thanks Bob. Can we get this sent to Linus as a fix during this cycle?
> 
> Andy
> 

It might need a

Fixes: 1f52aa08d12f8d359e71b4bfd73ca9d5d668e4da

That commit went upstream during this cycle's merge window so if we can 
get the fix upstream before release we won't have to worry about stable.

Andy