selinux: Fix an uninitialized variable BUG/panic in selinux_secattr_to_sid()

At some point during the 2.6.27 development cycle two new fields were added
to the SELinux context structure, a string pointer and a length field.  The
code in selinux_secattr_to_sid() was not modified and as a result these two
fields were left uninitialized which could result in erratic behavior,
including kernel panics, when NetLabel is used.  This patch fixes the
problem by fully initializing the context in selinux_secattr_to_sid() before
use and reducing the level of direct context manipulation done to help
prevent future problems.

Please apply this to the 2.6.27-rcX release stream.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
Paul Moore 2008-10-03 10:51:15 -04:00 committed by James Morris
parent b5ff7df3df
commit 3040a6d5a2
1 changed files with 4 additions and 7 deletions

View File

@ -2737,6 +2737,7 @@ int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
if (ctx == NULL)
goto netlbl_secattr_to_sid_return;
context_init(&ctx_new);
ctx_new.user = ctx->user;
ctx_new.role = ctx->role;
ctx_new.type = ctx->type;
@ -2745,13 +2746,9 @@ int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
secattr->attr.mls.cat) != 0)
goto netlbl_secattr_to_sid_return;
ctx_new.range.level[1].cat.highbit =
ctx_new.range.level[0].cat.highbit;
ctx_new.range.level[1].cat.node =
ctx_new.range.level[0].cat.node;
} else {
ebitmap_init(&ctx_new.range.level[0].cat);
ebitmap_init(&ctx_new.range.level[1].cat);
memcpy(&ctx_new.range.level[1].cat,
&ctx_new.range.level[0].cat,
sizeof(ctx_new.range.level[0].cat));
}
if (mls_context_isvalid(&policydb, &ctx_new) != 1)
goto netlbl_secattr_to_sid_return_cleanup;