Fix attached. Tentatively merged into cifs-2.6.git for-next pending review and the usual "buildbot" automated regression testing On Fri, Sep 13, 2019 at 12:09 PM Pavel Shilovsky via samba-technical <samba-technical@xxxxxxxxxxxxxxx> wrote: > > Yes, this is a bug. > > Steve, let's move > > + mid->callback(mid); > + > + cifs_mid_q_entry_release(mid); > > under ELSE {} block above. > > We should probably move > > + dw->server->lstrp = jiffies; > > before we looking for a mid. > > -- > Best regards, > Pavel Shilovsky > > пт, 13 сент. 2019 г. в 06:47, Dan Carpenter <dan.carpenter@xxxxxxxxxx>: > > > > tree: git://git.samba.org/sfrench/cifs-2.6.git for-next > > head: 5fc321fb644fc787710353be11129edadd313f3a > > commit: a091c5f67c994d154e8faf95ab774644be2f4dd7 [24/31] smb3: allow parallelizing decryption of reads > > > > If you fix the issue, kindly add following tag > > Reported-by: kbuild test robot <lkp@xxxxxxxxx> > > Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > > > > New smatch warnings: > > fs/cifs/smb2ops.c:4056 smb2_decrypt_offload() error: we previously assumed 'mid' could be null (see line 4045) > > > > git remote add cifs git://git.samba.org/sfrench/cifs-2.6.git > > git remote update cifs > > git checkout a091c5f67c994d154e8faf95ab774644be2f4dd7 > > vim +/mid +4056 fs/cifs/smb2ops.c > > > > a091c5f67c994d Steve French 2019-09-07 4030 static void smb2_decrypt_offload(struct work_struct *work) > > a091c5f67c994d Steve French 2019-09-07 4031 { > > a091c5f67c994d Steve French 2019-09-07 4032 struct smb2_decrypt_work *dw = container_of(work, > > a091c5f67c994d Steve French 2019-09-07 4033 struct smb2_decrypt_work, decrypt); > > a091c5f67c994d Steve French 2019-09-07 4034 int i, rc; > > a091c5f67c994d Steve French 2019-09-07 4035 struct mid_q_entry *mid; > > a091c5f67c994d Steve French 2019-09-07 4036 > > a091c5f67c994d Steve French 2019-09-07 4037 rc = decrypt_raw_data(dw->server, dw->buf, dw->server->vals->read_rsp_size, > > a091c5f67c994d Steve French 2019-09-07 4038 dw->ppages, dw->npages, dw->len); > > a091c5f67c994d Steve French 2019-09-07 4039 if (rc) { > > a091c5f67c994d Steve French 2019-09-07 4040 cifs_dbg(VFS, "error decrypting rc=%d\n", rc); > > a091c5f67c994d Steve French 2019-09-07 4041 goto free_pages; > > a091c5f67c994d Steve French 2019-09-07 4042 } > > a091c5f67c994d Steve French 2019-09-07 4043 > > a091c5f67c994d Steve French 2019-09-07 4044 mid = smb2_find_mid(dw->server, dw->buf); > > a091c5f67c994d Steve French 2019-09-07 @4045 if (mid == NULL) > > a091c5f67c994d Steve French 2019-09-07 4046 cifs_dbg(FYI, "mid not found\n"); > > > > Return here? > > > > a091c5f67c994d Steve French 2019-09-07 4047 else { > > a091c5f67c994d Steve French 2019-09-07 4048 mid->decrypted = true; > > a091c5f67c994d Steve French 2019-09-07 4049 rc = handle_read_data(dw->server, mid, dw->buf, > > a091c5f67c994d Steve French 2019-09-07 4050 dw->server->vals->read_rsp_size, > > a091c5f67c994d Steve French 2019-09-07 4051 dw->ppages, dw->npages, dw->len); > > a091c5f67c994d Steve French 2019-09-07 4052 } > > a091c5f67c994d Steve French 2019-09-07 4053 > > a091c5f67c994d Steve French 2019-09-07 4054 dw->server->lstrp = jiffies; > > a091c5f67c994d Steve French 2019-09-07 4055 > > a091c5f67c994d Steve French 2019-09-07 @4056 mid->callback(mid); > > ^^^^^^^^^^^^^ > > Potential NULL derference. > > > > a091c5f67c994d Steve French 2019-09-07 4057 > > a091c5f67c994d Steve French 2019-09-07 4058 cifs_mid_q_entry_release(mid); > > a091c5f67c994d Steve French 2019-09-07 4059 > > a091c5f67c994d Steve French 2019-09-07 4060 free_pages: > > a091c5f67c994d Steve French 2019-09-07 4061 for (i = dw->npages-1; i >= 0; i--) > > a091c5f67c994d Steve French 2019-09-07 4062 put_page(dw->ppages[i]); > > a091c5f67c994d Steve French 2019-09-07 4063 > > a091c5f67c994d Steve French 2019-09-07 4064 kfree(dw->ppages); > > a091c5f67c994d Steve French 2019-09-07 4065 cifs_small_buf_release(dw->buf); > > a091c5f67c994d Steve French 2019-09-07 4066 } > > > > --- > > 0-DAY kernel test infrastructure Open Source Technology Center > > https://lists.01.org/pipermail/kbuild-all Intel Corporation > -- Thanks, Steve
From 9b6ecf32499b32259ea306fc3e150ce2337a8b7b Mon Sep 17 00:00:00 2001 From: Steve French <stfrench@xxxxxxxxxxxxx> Date: Fri, 13 Sep 2019 16:47:31 -0500 Subject: [PATCH] smb3: fix potential null dereference in decrypt offload commit a091c5f67c99 ("smb3: allow parallelizing decryption of reads") had a potential null dereference Reported-by: kbuild test robot <lkp@xxxxxxxxx> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Suggested-by: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> --- fs/cifs/smb2ops.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 5776d7b0a97e..eaed18061314 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -4055,6 +4055,7 @@ static void smb2_decrypt_offload(struct work_struct *work) goto free_pages; } + dw->server->lstrp = jiffies; mid = smb2_find_mid(dw->server, dw->buf); if (mid == NULL) cifs_dbg(FYI, "mid not found\n"); @@ -4063,14 +4064,10 @@ static void smb2_decrypt_offload(struct work_struct *work) rc = handle_read_data(dw->server, mid, dw->buf, dw->server->vals->read_rsp_size, dw->ppages, dw->npages, dw->len); + mid->callback(mid); + cifs_mid_q_entry_release(mid); } - dw->server->lstrp = jiffies; - - mid->callback(mid); - - cifs_mid_q_entry_release(mid); - free_pages: for (i = dw->npages-1; i >= 0; i--) put_page(dw->ppages[i]); -- 2.20.1