[PATCH -v2 3/3] filesystems: use has_capability_noaudit interface forreserved blocks checks

From: Eric Paris
Date: Mon Nov 03 2008 - 16:28:43 EST


ext[2,3,4], ufs, and ubifs all check for CAP_SYS_RESOURCE to determine
if they should allow reserved blocks to be used. A process not having
this capability is not failing some security decision and should not be
audited. Thus move to using has_capability_noaudit.

Signed-off-by: Eric Paris <eparis@xxxxxxxxxx>
---

fs/ext2/balloc.c | 2 +-
fs/ext3/balloc.c | 2 +-
fs/ext4/balloc.c | 2 +-
fs/ubifs/budget.c | 3 ++-
fs/ufs/balloc.c | 2 +-
security/commoncap.c | 1 +
security/security.c | 1 +
7 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c
index 6dac7ba..e06d96d 100644
--- a/fs/ext2/balloc.c
+++ b/fs/ext2/balloc.c
@@ -1192,7 +1192,7 @@ static int ext2_has_free_blocks(struct ext2_sb_info *sbi)

free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
root_blocks = le32_to_cpu(sbi->s_es->s_r_blocks_count);
- if (free_blocks < root_blocks + 1 && !capable(CAP_SYS_RESOURCE) &&
+ if (free_blocks < root_blocks + 1 && !has_capability_noaudit(current, CAP_SYS_RESOURCE) &&
sbi->s_resuid != current->fsuid &&
(sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) {
return 0;
diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c
index f5b57a2..f224ee4 100644
--- a/fs/ext3/balloc.c
+++ b/fs/ext3/balloc.c
@@ -1421,7 +1421,7 @@ static int ext3_has_free_blocks(struct ext3_sb_info *sbi)

free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
root_blocks = le32_to_cpu(sbi->s_es->s_r_blocks_count);
- if (free_blocks < root_blocks + 1 && !capable(CAP_SYS_RESOURCE) &&
+ if (free_blocks < root_blocks + 1 && !has_capability_noaudit(current, CAP_SYS_RESOURCE) &&
sbi->s_resuid != current->fsuid &&
(sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) {
return 0;
diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index d2003cd..a7c7c52 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -626,7 +626,7 @@ int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks)
/* Hm, nope. Are (enough) root reserved blocks available? */
if (sbi->s_resuid == current->fsuid ||
((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) ||
- capable(CAP_SYS_RESOURCE)) {
+ has_capability_noaudit(current, CAP_SYS_RESOURCE)) {
if (free_blocks >= (nblocks + dirty_blocks))
return 1;
}
diff --git a/fs/ubifs/budget.c b/fs/ubifs/budget.c
index 1a4973e..d17b8b4 100644
--- a/fs/ubifs/budget.c
+++ b/fs/ubifs/budget.c
@@ -32,6 +32,7 @@

#include "ubifs.h"
#include <linux/writeback.h>
+#include <linux/capability.h>
#include <asm/div64.h>

/*
@@ -363,7 +364,7 @@ long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs)
*/
static int can_use_rp(struct ubifs_info *c)
{
- if (current->fsuid == c->rp_uid || capable(CAP_SYS_RESOURCE) ||
+ if (current->fsuid == c->rp_uid || has_capability_noaudit(current, CAP_SYS_RESOURCE) ||
(c->rp_gid != 0 && in_group_p(c->rp_gid)))
return 1;
return 0;
diff --git a/fs/ufs/balloc.c b/fs/ufs/balloc.c
index 0d9ada1..ad4398b 100644
--- a/fs/ufs/balloc.c
+++ b/fs/ufs/balloc.c
@@ -411,7 +411,7 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
/*
* There is not enough space for user on the device
*/
- if (!capable(CAP_SYS_RESOURCE) && ufs_freespace(uspi, UFS_MINFREE) <= 0) {
+ if (!has_capability_noaudit(current, CAP_SYS_RESOURCE) && ufs_freespace(uspi, UFS_MINFREE) <= 0) {
unlock_super (sb);
UFSD("EXIT (FAILED)\n");
return 0;
diff --git a/security/commoncap.c b/security/commoncap.c
index 73999f6..5401e77 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -55,6 +55,7 @@ int cap_capable(struct task_struct *tsk, int cap, int audit)
return 0;
return -EPERM;
}
+EXPORT_SYMBOL(cap_capable);

int cap_settime(struct timespec *ts, struct timezone *tz)
{
diff --git a/security/security.c b/security/security.c
index 346f21e..d061eb1 100644
--- a/security/security.c
+++ b/security/security.c
@@ -170,6 +170,7 @@ int security_capable_noaudit(struct task_struct *tsk, int cap)
{
return security_ops->capable(tsk, cap, SECURITY_CAP_NOAUDIT);
}
+EXPORT_SYMBOL(security_capable_noaudit);

int security_acct(struct file *file)
{

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/