From: Christian Brauner <christian.brauner@ubuntu.com>
Date: Wed, 13 Oct 2021 11:38:14 +0000 (+0200)
Subject: conf: improve capability handling
X-Git-Tag: lxc-5.0.0~75^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F3994%2Fhead;p=thirdparty%2Flxc.git

conf: improve capability handling

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---

diff --git a/src/lxc/caps.c b/src/lxc/caps.c
index e464042d8..08dd62364 100644
--- a/src/lxc/caps.c
+++ b/src/lxc/caps.c
@@ -209,7 +209,8 @@ int lxc_caps_init(void)
 
 static long int _real_caps_last_cap(void)
 {
-	int fd, result = -1;
+	__do_close int fd = -EBADF;
+	__s32 result = -1;
 
 	/* Try to get the maximum capability over the kernel interface
 	 * introduced in v3.2.
@@ -230,7 +231,7 @@ static long int _real_caps_last_cap(void)
 
 		close(fd);
 	} else {
-		int cap = 0;
+		__s32 cap = 0;
 
 		/* Try to get it manually by trying to get the status of each
 		 * capability individually from the kernel.
@@ -246,7 +247,7 @@ static long int _real_caps_last_cap(void)
 
 int lxc_caps_last_cap(void)
 {
-	static long int last_cap = -1;
+	static __s32 last_cap = -1;
 
 	if (last_cap < 0) {
 		last_cap = _real_caps_last_cap();
diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index a185acc5c..ad4c5ca14 100644
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -3176,11 +3176,11 @@ static int capabilities_deny(struct lxc_conf *conf)
 static int capabilities_allow(struct lxc_conf *conf)
 {
 	__do_free __u32 *keep_bits = NULL;
-	int numcaps;
+	__s32 numcaps;
 	struct cap_entry *cap;
 	size_t nr_u32;
 
-	numcaps = lxc_caps_last_cap() + 1;
+	numcaps = lxc_caps_last_cap();
 	if (numcaps <= 0 || numcaps > 200)
 		return ret_errno(EINVAL);
 
@@ -3192,14 +3192,14 @@ static int capabilities_allow(struct lxc_conf *conf)
 		return ret_errno(ENOMEM);
 
 	list_for_each_entry(cap, &conf->caps.list, head) {
-		if (cap->cap >= numcaps)
+		if (cap->cap > numcaps)
 			continue;
 
 		set_bit(cap->cap, keep_bits);
 		DEBUG("Keeping %s (%d) capability", cap->cap_name, cap->cap);
 	}
 
-	for (int cap_bit = 0; cap_bit < numcaps; cap_bit++) {
+	for (__s32 cap_bit = 0; cap_bit <= numcaps; cap_bit++) {
 		int ret;
 
 		if (is_set(cap_bit, keep_bits))
diff --git a/src/lxc/macro.h b/src/lxc/macro.h
index ab0950c7e..291d158b2 100644
--- a/src/lxc/macro.h
+++ b/src/lxc/macro.h
@@ -770,19 +770,19 @@ typedef long long unsigned int llu;
 #define DIV_ROUND_UP(n, d) (((n) + (d)-1) / (d))
 #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, NBITS)
 
-static inline void set_bit(unsigned bit, uint32_t *bitarr)
+static inline void set_bit(__u32 bit, __u32 *bitarr)
 {
-	bitarr[bit / NBITS] |= (1 << (bit % NBITS));
+	bitarr[bit / NBITS] |= ((__u32)1 << (bit % NBITS));
 }
 
-static inline void clear_bit(unsigned bit, uint32_t *bitarr)
+static inline void clear_bit(__u32 bit, __u32 *bitarr)
 {
-	bitarr[bit / NBITS] &= ~(1 << (bit % NBITS));
+	bitarr[bit / NBITS] &= ~((__u32)1 << (bit % NBITS));
 }
 
-static inline bool is_set(unsigned bit, uint32_t *bitarr)
+static inline bool is_set(__u32 bit, __u32 *bitarr)
 {
-	return (bitarr[bit / NBITS] & (1 << (bit % NBITS))) != 0;
+	return (bitarr[bit / NBITS] & ((__u32)1 << (bit % NBITS))) != 0;
 }
 
 #endif /* __LXC_MACRO_H */