Commit 00e0590d authored Jun 27, 2019 by Colin Ian King Committed by John Johansen Nov 22, 2019

apparmor: fix unsigned len comparison with less than zero



The sanity check in macro update_for_len checks to see if len
is less than zero, however, len is a size_t so it can never be
less than zero, so this sanity check is a no-op.  Fix this by
making len a ssize_t so the comparison will work and add ulen
that is a size_t copy of len so that the min() macro won't
throw warnings about comparing different types.

Addresses-Coverity: ("Macro compares unsigned to 0")
Fixes: f1bd9041 ("apparmor: add the base fns() for domain labels")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

parent 136db994

security/apparmor/label.c

+7 −5

Original line number	Diff line number	Diff line
		@@ -1462,11 +1462,13 @@ static inline bool use_label_hname(struct aa_ns ns, struct aa_label label,
		/* helper macro for snprint routines */
		#define update_for_len(total, len, size, str) \
		do { \
		size_t ulen = len; \
		\
		AA_BUG(len < 0); \
		total += len; \
		len = min(len, size); \
		size -= len; \
		str += len; \
		total += ulen; \
		ulen = min(ulen, size); \
		size -= ulen; \
		str += ulen; \
		} while (0)

		/**
		@@ -1601,7 +1603,7 @@ int aa_label_snxprint(char str, size_t size, struct aa_ns ns,
		struct aa_ns *prev_ns = NULL;
		struct label_it i;
		int count = 0, total = 0;
		size_t len;
		ssize_t len;

		AA_BUG(!str && size != 0);
		AA_BUG(!label);

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