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| author | Al Viro <viro@zeniv.linux.org.uk> | 2021-01-05 14:43:46 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-01-19 18:26:16 +0100 |
| commit | 08eb8a735c113ff945a6f08c569b99dae3543a92 (patch) | |
| tree | 8897ba435d006de43d7c21f4aae16b52d93b26d1 /security | |
| parent | d443cefd9f733b037f3b82424823ba993a87062c (diff) | |
| download | linux-stable-08eb8a735c113ff945a6f08c569b99dae3543a92.tar.gz linux-stable-08eb8a735c113ff945a6f08c569b99dae3543a92.tar.bz2 linux-stable-08eb8a735c113ff945a6f08c569b99dae3543a92.zip | |
dump_common_audit_data(): fix racy accesses to ->d_name
commit d36a1dd9f77ae1e72da48f4123ed35627848507d upstream.
We are not guaranteed the locking environment that would prevent
dentry getting renamed right under us. And it's possible for
old long name to be freed after rename, leading to UAF here.
Cc: stable@kernel.org # v2.6.2+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'security')
| -rw-r--r-- | security/lsm_audit.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/security/lsm_audit.c b/security/lsm_audit.c index e40874373f2b..d025f575a9e3 100644 --- a/security/lsm_audit.c +++ b/security/lsm_audit.c @@ -274,7 +274,9 @@ static void dump_common_audit_data(struct audit_buffer *ab, struct inode *inode; audit_log_format(ab, " name="); + spin_lock(&a->u.dentry->d_lock); audit_log_untrustedstring(ab, a->u.dentry->d_name.name); + spin_unlock(&a->u.dentry->d_lock); inode = d_backing_inode(a->u.dentry); if (inode) { @@ -292,8 +294,9 @@ static void dump_common_audit_data(struct audit_buffer *ab, dentry = d_find_alias(inode); if (dentry) { audit_log_format(ab, " name="); - audit_log_untrustedstring(ab, - dentry->d_name.name); + spin_lock(&dentry->d_lock); + audit_log_untrustedstring(ab, dentry->d_name.name); + spin_unlock(&dentry->d_lock); dput(dentry); } audit_log_format(ab, " dev="); |