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Diffstat (limited to 'fs/cifs/smb2misc.c')
-rw-r--r--fs/cifs/smb2misc.c49
1 files changed, 29 insertions, 20 deletions
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 17813c3d0c6e..818cc4dee0e2 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -132,15 +132,15 @@ static __u32 get_neg_ctxt_len(struct smb2_hdr *hdr, __u32 len,
}
int
-smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
+smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
{
struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
- __u64 mid;
- __u32 clc_len; /* calculated length */
- int command;
- int pdu_size = sizeof(struct smb2_pdu);
int hdr_size = sizeof(struct smb2_hdr);
+ int pdu_size = sizeof(struct smb2_pdu);
+ int command;
+ __u32 calc_len; /* calculated length */
+ __u64 mid;
/*
* Add function to do table lookup of StructureSize by command
@@ -154,7 +154,7 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
/* decrypt frame now that it is completely read in */
spin_lock(&cifs_tcp_ses_lock);
- list_for_each_entry(iter, &srvr->smb_ses_list, smb_ses_list) {
+ list_for_each_entry(iter, &server->smb_ses_list, smb_ses_list) {
if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
ses = iter;
break;
@@ -221,30 +221,33 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
}
}
- clc_len = smb2_calc_size(buf, srvr);
+ calc_len = smb2_calc_size(buf, server);
+
+ /* For SMB2_IOCTL, OutputOffset and OutputLength are optional, so might
+ * be 0, and not a real miscalculation */
+ if (command == SMB2_IOCTL_HE && calc_len == 0)
+ return 0;
- if (shdr->Command == SMB2_NEGOTIATE)
- clc_len += get_neg_ctxt_len(shdr, len, clc_len);
+ if (command == SMB2_NEGOTIATE_HE)
+ calc_len += get_neg_ctxt_len(shdr, len, calc_len);
- if (len != clc_len) {
- cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
- clc_len, len, mid);
+ if (len != calc_len) {
/* create failed on symlink */
if (command == SMB2_CREATE_HE &&
shdr->Status == STATUS_STOPPED_ON_SYMLINK)
return 0;
/* Windows 7 server returns 24 bytes more */
- if (clc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
+ if (calc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
return 0;
/* server can return one byte more due to implied bcc[0] */
- if (clc_len == len + 1)
+ if (calc_len == len + 1)
return 0;
/*
* Some windows servers (win2016) will pad also the final
* PDU in a compound to 8 bytes.
*/
- if (((clc_len + 7) & ~7) == len)
+ if (((calc_len + 7) & ~7) == len)
return 0;
/*
@@ -253,12 +256,18 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
* SMB2/SMB3 frame length (header + smb2 response specific data)
* Some windows servers also pad up to 8 bytes when compounding.
*/
- if (clc_len < len)
+ if (calc_len < len)
return 0;
- pr_warn_once(
- "srv rsp too short, len %d not %d. cmd:%d mid:%llu\n",
- len, clc_len, command, mid);
+ /* Only log a message if len was really miscalculated */
+ if (unlikely(cifsFYI))
+ cifs_dbg(FYI, "Server response too short: calculated "
+ "length %u doesn't match read length %u (cmd=%d, mid=%llu)\n",
+ calc_len, len, command, mid);
+ else
+ pr_warn("Server response too short: calculated length "
+ "%u doesn't match read length %u (cmd=%d, mid=%llu)\n",
+ calc_len, len, command, mid);
return 1;
}
@@ -402,7 +411,7 @@ smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
unsigned int
smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
{
- struct smb2_pdu *pdu = (struct smb2_pdu *)buf;
+ struct smb2_pdu *pdu = buf;
struct smb2_hdr *shdr = &pdu->hdr;
int offset; /* the offset from the beginning of SMB to data area */
int data_length; /* the length of the variable length data area */