4.19-stable review patch. If anyone has any objections, please let me know.
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From: Roberto Sassu roberto.sassu@huawei.com
commit 3a3d8fce31a49363cc31880dce5e3b0617c9c38b upstream.
Enhance smack_inode_getsecurity() to retrieve the value for SMACK64TRANSMUTE from the inode security blob, similarly to SMACK64.
This helps to display accurate values in the situation where the security labels come from mount options and not from xattrs.
Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Casey Schaufler casey@schaufler-ca.com [4.19: adjusted for the lack of helper functions] Fixes: d6d80cb57be4 ("Smack: Base support for overlayfs") Signed-off-by: Munehisa Kamata kamatam@amazon.com Signed-off-by: Sasha Levin sashal@kernel.org --- security/smack/smack_lsm.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index a09a9c6bbdf63..db729834d8ba9 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -1490,10 +1490,19 @@ static int smack_inode_getsecurity(struct inode *inode, struct super_block *sbp; struct inode *ip = (struct inode *)inode; struct smack_known *isp; + struct inode_smack *ispp; + size_t label_len; + char *label = NULL;
- if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) + if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { isp = smk_of_inode(inode); - else { + } else if (strcmp(name, XATTR_SMACK_TRANSMUTE) == 0) { + ispp = inode->i_security; + if (ispp->smk_flags & SMK_INODE_TRANSMUTE) + label = TRANS_TRUE; + else + label = ""; + } else { /* * The rest of the Smack xattrs are only on sockets. */ @@ -1515,13 +1524,18 @@ static int smack_inode_getsecurity(struct inode *inode, return -EOPNOTSUPP; }
+ if (!label) + label = isp->smk_known; + + label_len = strlen(label); + if (alloc) { - *buffer = kstrdup(isp->smk_known, GFP_KERNEL); + *buffer = kstrdup(label, GFP_KERNEL); if (*buffer == NULL) return -ENOMEM; }
- return strlen(isp->smk_known); + return label_len; }