diff options
| author | Pavel Shilovsky <piastry@etersoft.ru> | 2014-02-14 10:31:02 +0100 |
|---|---|---|
| committer | Steve French <smfrench@gmail.com> | 2014-02-14 23:50:47 +0100 |
| commit | 2365c4eaf077c48574ab6f143960048fc0f31518 (patch) | |
| tree | d710354608b5fe6a559dc5c0045ab0e6104ffe28 /fs/cifs | |
| parent | cifs: ensure that uncached writes handle unmapped areas correctly (diff) | |
| download | linux-2365c4eaf077c48574ab6f143960048fc0f31518.tar.xz linux-2365c4eaf077c48574ab6f143960048fc0f31518.zip | |
CIFS: Fix too big maxBuf size for SMB3 mounts
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.
Cc: stable@vger.kernel.org # 3.7+
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Diffstat (limited to 'fs/cifs')
| -rw-r--r-- | fs/cifs/smb2glob.h | 3 | ||||
| -rw-r--r-- | fs/cifs/smb2ops.c | 14 | ||||
| -rw-r--r-- | fs/cifs/smb2pdu.c | 4 |
3 files changed, 10 insertions, 11 deletions
diff --git a/fs/cifs/smb2glob.h b/fs/cifs/smb2glob.h index c38350851b08..bc0bb9c34f72 100644 --- a/fs/cifs/smb2glob.h +++ b/fs/cifs/smb2glob.h @@ -57,4 +57,7 @@ #define SMB2_CMACAES_SIZE (16) #define SMB3_SIGNKEY_SIZE (16) +/* 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 757da3e54d3d..192f51a12cf1 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -182,11 +182,8 @@ 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; } @@ -200,11 +197,8 @@ 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 a3f7a9c3cc69..860344701067 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -413,7 +413,9 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) /* SMB2 only has an extended negflavor */ server->negflavor = CIFS_NEGFLAVOR_EXTENDED; - 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? */ |