From: Meetakshi Setiya <meetakshisetiyaoss@gmail.com>
To: Steve French <smfrench@gmail.com>
Cc: Paulo Alcantara <pc@manguebit.com>, linux-cifs@vger.kernel.org
Subject: Re: [PATCH] smb: client: fix NULL ptr deref in cifs_mark_open_handles_for_deleted_file()
Date: Tue, 9 Apr 2024 12:01:11 +0530 [thread overview]
Message-ID: <CAFTVevUm5_FsMWq5n30zVbApbf5CtHV4Y3tZzr3bBLFV4dmvoQ@mail.gmail.com> (raw)
In-Reply-To: <CAH2r5msiCzzP-cHcnzqHuAM23N5a_55TLMg3crt=Z0F=bS=xcA@mail.gmail.com>
Thanks, looks good.
Meetakshi
On Tue, Apr 9, 2024 at 3:39 AM Steve French <smfrench@gmail.com> wrote:
>
> merged into cifs-2.6.git for-next
>
> Good catch
>
>
> On Mon, Apr 8, 2024 at 4:32 PM Paulo Alcantara <pc@manguebit.com> wrote:
> >
> > cifs_get_fattr() may be called with a NULL inode, so check for a
> > non-NULL inode before calling
> > cifs_mark_open_handles_for_deleted_file().
> >
> > This fixes the following oops:
> >
> > mount.cifs //srv/share /mnt -o ...,vers=3.1.1
> > cd /mnt
> > touch foo; tail -f foo &
> > rm foo
> > cat foo
> >
> > BUG: kernel NULL pointer dereference, address: 00000000000005c0
> > #PF: supervisor read access in kernel mode
> > #PF: error_code(0x0000) - not-present page
> > PGD 0 P4D 0
> > Oops: 0000 [#1] PREEMPT SMP NOPTI
> > CPU: 2 PID: 696 Comm: cat Not tainted 6.9.0-rc2 #1
> > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
> > 1.16.3-1.fc39 04/01/2014
> > RIP: 0010:__lock_acquire+0x5d/0x1c70
> > Code: 00 00 44 8b a4 24 a0 00 00 00 45 85 f6 0f 84 bb 06 00 00 8b 2d
> > 48 e2 95 01 45 89 c3 41 89 d2 45 89 c8 85 ed 0 0 <48> 81 3f 40 7a 76
> > 83 44 0f 44 d8 83 fe 01 0f 86 1b 03 00 00 31 d2
> > RSP: 0018:ffffc90000b37490 EFLAGS: 00010002
> > RAX: 0000000000000000 RBX: ffff888110021ec0 RCX: 0000000000000000
> > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000005c0
> > RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
> > R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
> > R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000200
> > FS: 00007f2a1fa08740(0000) GS:ffff888157a00000(0000)
> > knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0:
> > 0000000080050033
> > CR2: 00000000000005c0 CR3: 000000011ac7c000 CR4: 0000000000750ef0
> > PKRU: 55555554
> > Call Trace:
> > <TASK>
> > ? __die+0x23/0x70
> > ? page_fault_oops+0x180/0x490
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > ? exc_page_fault+0x70/0x230
> > ? asm_exc_page_fault+0x26/0x30
> > ? __lock_acquire+0x5d/0x1c70
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > lock_acquire+0xc0/0x2d0
> > ? cifs_mark_open_handles_for_deleted_file+0x3a/0x100 [cifs]
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > ? kmem_cache_alloc+0x2d9/0x370
> > _raw_spin_lock+0x34/0x80
> > ? cifs_mark_open_handles_for_deleted_file+0x3a/0x100 [cifs]
> > cifs_mark_open_handles_for_deleted_file+0x3a/0x100 [cifs]
> > cifs_get_fattr+0x24c/0x940 [cifs]
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > cifs_get_inode_info+0x96/0x120 [cifs]
> > cifs_lookup+0x16e/0x800 [cifs]
> > cifs_atomic_open+0xc7/0x5d0 [cifs]
> > ? lookup_open.isra.0+0x3ce/0x5f0
> > ? __pfx_cifs_atomic_open+0x10/0x10 [cifs]
> > lookup_open.isra.0+0x3ce/0x5f0
> > path_openat+0x42b/0xc30
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > do_filp_open+0xc4/0x170
> > do_sys_openat2+0xab/0xe0
> > __x64_sys_openat+0x57/0xa0
> > do_syscall_64+0xc1/0x1e0
> > entry_SYSCALL_64_after_hwframe+0x72/0x7a
> >
> > Fixes: ffceb7640cbf ("smb: client: do not defer close open handles to deleted files")
> > Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
> > ---
> > fs/smb/client/inode.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/fs/smb/client/inode.c b/fs/smb/client/inode.c
> > index 91b07ef9e25c..60afab5c83d4 100644
> > --- a/fs/smb/client/inode.c
> > +++ b/fs/smb/client/inode.c
> > @@ -1105,7 +1105,8 @@ static int cifs_get_fattr(struct cifs_open_info_data *data,
> > } else {
> > cifs_open_info_to_fattr(fattr, data, sb);
> > }
> > - if (!rc && fattr->cf_flags & CIFS_FATTR_DELETE_PENDING)
> > + if (!rc && *inode &&
> > + (fattr->cf_flags & CIFS_FATTR_DELETE_PENDING))
> > cifs_mark_open_handles_for_deleted_file(*inode, full_path);
> > break;
> > case -EREMOTE:
> > --
> > 2.44.0
> >
>
>
> --
> Thanks,
>
> Steve
>
prev parent reply other threads:[~2024-04-09 6:31 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-08 21:32 [PATCH] smb: client: fix NULL ptr deref in cifs_mark_open_handles_for_deleted_file() Paulo Alcantara
2024-04-08 22:09 ` Steve French
2024-04-09 6:31 ` Meetakshi Setiya [this message]
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