diff options
| author | Steve French <sfrench@us.ibm.com> | 2008-10-08 19:13:46 +0000 |
|---|---|---|
| committer | Steve French <sfrench@us.ibm.com> | 2008-10-08 19:13:46 +0000 |
| commit | b77d753c413e02559669df66e543869dad40c847 (patch) | |
| tree | 95946079a0b58c06a6e98b22b06f86a89fe68749 | |
| parent | 0752f1522a9120f731232919f7ad904e9e22b8ce (diff) | |
| download | linux-b77d753c413e02559669df66e543869dad40c847.tar.bz2 | |
[CIFS] Check that last search entry resume key is valid
Jeff's recent patch to add a last_entry field in the search structure
to better construct resume keys did not validate that the server
sent us a plausible pointer to the last entry. This adds that.
Signed-off-by: Steve French <sfrench@us.ibm.com>
| -rw-r--r-- | fs/cifs/cifssmb.c | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 7b00a16e1352..6f4ffe15d68d 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -3614,6 +3614,8 @@ findFirstRetry: /* BB remember to free buffer if error BB */ rc = validate_t2((struct smb_t2_rsp *)pSMBr); if (rc == 0) { + unsigned int lnoff; + if (pSMBr->hdr.Flags2 & SMBFLG2_UNICODE) psrch_inf->unicode = true; else @@ -3636,8 +3638,17 @@ findFirstRetry: le16_to_cpu(parms->SearchCount); psrch_inf->index_of_last_entry = 2 /* skip . and .. */ + psrch_inf->entries_in_buffer; + lnoff = le16_to_cpu(parms->LastNameOffset); + if (tcon->ses->server->maxBuf - MAX_CIFS_HDR_SIZE < + lnoff) { + cERROR(1, ("ignoring corrupt resume name")); + psrch_inf->last_entry = NULL; + return rc; + } + psrch_inf->last_entry = psrch_inf->srch_entries_start + - le16_to_cpu(parms->LastNameOffset); + lnoff; + *pnetfid = parms->SearchHandle; } else { cifs_buf_release(pSMB); @@ -3727,6 +3738,8 @@ int CIFSFindNext(const int xid, struct cifsTconInfo *tcon, rc = validate_t2((struct smb_t2_rsp *)pSMBr); if (rc == 0) { + unsigned int lnoff; + /* BB fixme add lock for file (srch_info) struct here */ if (pSMBr->hdr.Flags2 & SMBFLG2_UNICODE) psrch_inf->unicode = true; @@ -3753,8 +3766,16 @@ int CIFSFindNext(const int xid, struct cifsTconInfo *tcon, le16_to_cpu(parms->SearchCount); psrch_inf->index_of_last_entry += psrch_inf->entries_in_buffer; - psrch_inf->last_entry = psrch_inf->srch_entries_start + - le16_to_cpu(parms->LastNameOffset); + lnoff = le16_to_cpu(parms->LastNameOffset); + if (tcon->ses->server->maxBuf - MAX_CIFS_HDR_SIZE < + lnoff) { + cERROR(1, ("ignoring corrupt resume name")); + psrch_inf->last_entry = NULL; + return rc; + } else + psrch_inf->last_entry = + psrch_inf->srch_entries_start + lnoff; + /* cFYI(1,("fnxt2 entries in buf %d index_of_last %d", psrch_inf->entries_in_buffer, psrch_inf->index_of_last_entry)); */ |