[PATCH 3.8 64/81] cifs: Fix inability to write files >2GB to SMB2/3 shares

From: Kamal Mostafa
Date: Tue Oct 29 2013 - 14:24:07 EST -stable review patch. If anyone has any objections, please let me know.


From: Jan Klos <honza.klos@xxxxxxxxx>

commit 2f6c9479633780ba4a3484bba7eba5a721a5cf20 upstream.

When connecting to SMB2/3 shares, maximum file size is set to non-LFS maximum in superblock. This is due to cap_large_files bit being different for SMB1 and SMB2/3 (where it is just an internal flag that is not negotiated and the SMB1 one corresponds to multichannel capability, so maybe LFS works correctly if server sends 0x08 flag) while capabilities are checked always for the SMB1 bit in cifs_read_super().

The patch fixes this by checking for the correct bit according to the protocol version.

Signed-off-by: Jan Klos <honza.klos@xxxxxxxxx>
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
[ kamal: backport to 3.8 (context) ]
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
fs/cifs/cifsfs.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index b9db388..e946529 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -120,14 +120,16 @@ cifs_read_super(struct super_block *sb)
struct inode *inode;
struct cifs_sb_info *cifs_sb;
+ struct cifs_tcon *tcon;
int rc = 0;

cifs_sb = CIFS_SB(sb);
+ tcon = cifs_sb_master_tcon(cifs_sb);

if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIXACL)
sb->s_flags |= MS_POSIXACL;

- if (cifs_sb_master_tcon(cifs_sb)->ses->capabilities & CAP_LARGE_FILES)
+ if (tcon->ses->capabilities & tcon->ses->server->vals->cap_large_files)
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_maxbytes = MAX_NON_LFS;
@@ -154,7 +156,7 @@ cifs_read_super(struct super_block *sb)

/* do that *after* d_make_root() - we want NULL ->d_op for root here */
- if (cifs_sb_master_tcon(cifs_sb)->nocase)
+ if (tcon->nocase)
sb->s_d_op = &cifs_ci_dentry_ops;
sb->s_d_op = &cifs_dentry_ops;

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/