6.12-stable review patch. If anyone has any objections, please let me know.
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From: Pali Rohár pali@kernel.org
[ Upstream commit ef201e8759d20bf82b5943101147072de12bc524 ]
Major and minor numbers for char and block devices are mandatory for stat. So check that the WSL EA $LXDEV is present for WSL CHR and BLK reparse points.
WSL reparse point tag determinate type of the file. But file type is present also in the WSL EA $LXMOD. So check that both file types are same.
Fixes: 78e26bec4d6d ("smb: client: parse uid, gid, mode and dev from WSL reparse points") Signed-off-by: Pali Rohár pali@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/smb/client/reparse.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c index d3abb99cc9909..e56a8df23fec9 100644 --- a/fs/smb/client/reparse.c +++ b/fs/smb/client/reparse.c @@ -674,11 +674,12 @@ int smb2_parse_reparse_point(struct cifs_sb_info *cifs_sb, return parse_reparse_point(buf, plen, cifs_sb, full_path, true, data); }
-static void wsl_to_fattr(struct cifs_open_info_data *data, +static bool wsl_to_fattr(struct cifs_open_info_data *data, struct cifs_sb_info *cifs_sb, u32 tag, struct cifs_fattr *fattr) { struct smb2_file_full_ea_info *ea; + bool have_xattr_dev = false; u32 next = 0;
switch (tag) { @@ -721,13 +722,24 @@ static void wsl_to_fattr(struct cifs_open_info_data *data, fattr->cf_uid = wsl_make_kuid(cifs_sb, v); else if (!strncmp(name, SMB2_WSL_XATTR_GID, nlen)) fattr->cf_gid = wsl_make_kgid(cifs_sb, v); - else if (!strncmp(name, SMB2_WSL_XATTR_MODE, nlen)) + else if (!strncmp(name, SMB2_WSL_XATTR_MODE, nlen)) { + /* File type in reparse point tag and in xattr mode must match. */ + if (S_DT(fattr->cf_mode) != S_DT(le32_to_cpu(*(__le32 *)v))) + return false; fattr->cf_mode = (umode_t)le32_to_cpu(*(__le32 *)v); - else if (!strncmp(name, SMB2_WSL_XATTR_DEV, nlen)) + } else if (!strncmp(name, SMB2_WSL_XATTR_DEV, nlen)) { fattr->cf_rdev = reparse_mkdev(v); + have_xattr_dev = true; + } } while (next); out: + + /* Major and minor numbers for char and block devices are mandatory. */ + if (!have_xattr_dev && (tag == IO_REPARSE_TAG_LX_CHR || tag == IO_REPARSE_TAG_LX_BLK)) + return false; + fattr->cf_dtype = S_DT(fattr->cf_mode); + return true; }
static bool posix_reparse_to_fattr(struct cifs_sb_info *cifs_sb, @@ -801,7 +813,9 @@ bool cifs_reparse_point_to_fattr(struct cifs_sb_info *cifs_sb, case IO_REPARSE_TAG_AF_UNIX: case IO_REPARSE_TAG_LX_CHR: case IO_REPARSE_TAG_LX_BLK: - wsl_to_fattr(data, cifs_sb, tag, fattr); + ok = wsl_to_fattr(data, cifs_sb, tag, fattr); + if (!ok) + return false; break; case IO_REPARSE_TAG_NFS: ok = posix_reparse_to_fattr(cifs_sb, fattr, data);