cifs: check ntwrk_buf_start for NULL before dereferencing it
[ Upstream commit 59a63e479ce36a3f24444c3a36efe82b78e4a8e0 ] RHBZ: 1021460 There is an issue where when multiple threads open/close the same directory ntwrk_buf_start might end up being NULL, causing the call to smbCalcSize later to oops with a NULL deref. The real bug is why this happens and why this can become NULL for an open cfile, which should not be allowed. This patch tries to avoid a oops until the time when we fix the underlying issue. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
parent
b49344a2dc
commit
7d1cfc10d4
1 changed files with 8 additions and 1 deletions
|
@ -652,7 +652,14 @@ find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos,
|
|||
/* scan and find it */
|
||||
int i;
|
||||
char *cur_ent;
|
||||
char *end_of_smb = cfile->srch_inf.ntwrk_buf_start +
|
||||
char *end_of_smb;
|
||||
|
||||
if (cfile->srch_inf.ntwrk_buf_start == NULL) {
|
||||
cifs_dbg(VFS, "ntwrk_buf_start is NULL during readdir\n");
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
end_of_smb = cfile->srch_inf.ntwrk_buf_start +
|
||||
server->ops->calc_smb_size(
|
||||
cfile->srch_inf.ntwrk_buf_start);
|
||||
|
||||
|
|
Loading…
Add table
Reference in a new issue