diff options
| author | Pavel Shilovsky <piastry@etersoft.ru> | 2014-02-14 13:31:02 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-03-06 21:30:02 -0800 |
| commit | 32c36d8888008fb30c8215d0fc189a288285bc12 (patch) | |
| tree | a90b72e03ed685764fdedf41fb4c90847dfbb776 /fs | |
| parent | 9f0afafeb7bdd6c2c2b27a93c803fff975a232be (diff) | |
CIFS: Fix too big maxBuf size for SMB3 mounts
commit 2365c4eaf077c48574ab6f143960048fc0f31518 upstream.
SMB3 servers can respond with MaxTransactSize of more than 4M
that can cause a memory allocation error returned from kmalloc
in a lock codepath. Also the client doesn't support multicredit
requests now and allows buffer sizes of 65536 bytes only. Set
MaxTransactSize to this maximum supported value.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/cifs/smb2glob.h | 3 | ||||
| -rw-r--r-- | fs/cifs/smb2ops.c | 14 | ||||
| -rw-r--r-- | fs/cifs/smb2pdu.c | 3 |
3 files changed, 10 insertions, 10 deletions
diff --git a/fs/cifs/smb2glob.h b/fs/cifs/smb2glob.h index 7c0e2143e775..cc592ef6584a 100644 --- a/fs/cifs/smb2glob.h +++ b/fs/cifs/smb2glob.h @@ -55,4 +55,7 @@ #define SMB2_NTLMV2_SESSKEY_SIZE (16) #define SMB2_HMACSHA256_SIZE (32) +/* Maximum buffer size value we can send with 1 credit */ +#define SMB2_MAX_BUFFER_SIZE 65536 + #endif /* _SMB2_GLOB_H */ diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index f2e76f3b0c61..e2756bb40b4d 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -181,11 +181,8 @@ smb2_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info) /* start with specified wsize, or default */ wsize = volume_info->wsize ? volume_info->wsize : CIFS_DEFAULT_IOSIZE; wsize = min_t(unsigned int, wsize, server->max_write); - /* - * limit write size to 2 ** 16, because we don't support multicredit - * requests now. - */ - wsize = min_t(unsigned int, wsize, 2 << 15); + /* set it to the maximum buffer size value we can send with 1 credit */ + wsize = min_t(unsigned int, wsize, SMB2_MAX_BUFFER_SIZE); return wsize; } @@ -199,11 +196,8 @@ smb2_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info) /* start with specified rsize, or default */ rsize = volume_info->rsize ? volume_info->rsize : CIFS_DEFAULT_IOSIZE; rsize = min_t(unsigned int, rsize, server->max_read); - /* - * limit write size to 2 ** 16, because we don't support multicredit - * requests now. - */ - rsize = min_t(unsigned int, rsize, 2 << 15); + /* set it to the maximum buffer size value we can send with 1 credit */ + rsize = min_t(unsigned int, rsize, SMB2_MAX_BUFFER_SIZE); return rsize; } diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 2b95ce2b54e8..c7a6fd87bb6e 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -408,6 +408,9 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) server->dialect = le16_to_cpu(rsp->DialectRevision); server->maxBuf = le32_to_cpu(rsp->MaxTransactSize); + /* set it to the maximum buffer size value we can send with 1 credit */ + server->maxBuf = min_t(unsigned int, le32_to_cpu(rsp->MaxTransactSize), + SMB2_MAX_BUFFER_SIZE); server->max_read = le32_to_cpu(rsp->MaxReadSize); server->max_write = le32_to_cpu(rsp->MaxWriteSize); /* BB Do we need to validate the SecurityMode? */ |