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| author | Paul Moore <paul@paul-moore.com> | 2024-10-25 11:20:21 -0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-11-01 01:58:33 +0100 |
| commit | 4512c448f54c52a6e7089a22cd769bc31ba3a493 (patch) | |
| tree | 144f2dc6f9ac40d36de63ba82251d7e81769fd32 | |
| parent | c79e0a18e4b301401bb745702830be9041cfbf04 (diff) | |
| download | linux-rpi-4512c448f54c52a6e7089a22cd769bc31ba3a493.tar.gz linux-rpi-4512c448f54c52a6e7089a22cd769bc31ba3a493.tar.bz2 linux-rpi-4512c448f54c52a6e7089a22cd769bc31ba3a493.zip | |
selinux: improve error checking in sel_write_load()
[ Upstream commit 42c773238037c90b3302bf37a57ae3b5c3f6004a ]
Move our existing input sanity checking to the top of sel_write_load()
and add a check to ensure the buffer size is non-zero.
Move a local variable initialization from the declaration to before it
is used.
Minor style adjustments.
Reported-by: Sam Sun <samsun1006219@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | security/selinux/selinuxfs.c | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 2c23a5a28608..54bc18e8164b 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -582,11 +582,18 @@ static ssize_t sel_write_load(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info; + struct selinux_fs_info *fsi; struct selinux_load_state load_state; ssize_t length; void *data = NULL; + /* no partial writes */ + if (*ppos) + return -EINVAL; + /* no empty policies */ + if (!count) + return -EINVAL; + mutex_lock(&selinux_state.policy_mutex); length = avc_has_perm(current_sid(), SECINITSID_SECURITY, @@ -594,26 +601,22 @@ static ssize_t sel_write_load(struct file *file, const char __user *buf, if (length) goto out; - /* No partial writes. */ - length = -EINVAL; - if (*ppos != 0) - goto out; - - length = -ENOMEM; data = vmalloc(count); - if (!data) + if (!data) { + length = -ENOMEM; goto out; - - length = -EFAULT; - if (copy_from_user(data, buf, count) != 0) + } + if (copy_from_user(data, buf, count) != 0) { + length = -EFAULT; goto out; + } length = security_load_policy(data, count, &load_state); if (length) { pr_warn_ratelimited("SELinux: failed to load policy\n"); goto out; } - + fsi = file_inode(file)->i_sb->s_fs_info; length = sel_make_policy_nodes(fsi, load_state.policy); if (length) { pr_warn_ratelimited("SELinux: failed to initialize selinuxfs\n"); @@ -622,13 +625,12 @@ static ssize_t sel_write_load(struct file *file, const char __user *buf, } selinux_policy_commit(&load_state); - length = count; - audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD, "auid=%u ses=%u lsm=selinux res=1", from_kuid(&init_user_ns, audit_get_loginuid(current)), audit_get_sessionid(current)); + out: mutex_unlock(&selinux_state.policy_mutex); vfree(data); |