Note: only rh7-3.10.0-693.17.1.el7-based kernels are affcted. I.e. starting from rh7-3.10.0-693.17.1.vz7.43.1.
Posix acl is used to convert of an extended attribute, provided by user to ext4 attributes. In particular to i_mode in case of ACL_TYPE_ACCESS request. IOW, this object is allocated, used for convertion, not stored anywhere and must be freed. However posix_acl_update_mode() can zerofy the pointer to support ext4_set_acl() logic, but then the object is leaked. So, fix it by releasing new temporary pointer with the same value instead of acl pointer. https://jira.sw.ru/browse/PSBM-81384 RHEL bug URL: https://bugzilla.redhat.com/show_bug.cgi?id=1543020 v2: Added affected kernel version + RHEL bug URL Signed-off-by: Stanislav Kinsburskiy <skinsbur...@virtuozzo.com> --- fs/ext4/acl.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c index 917e819..f8a38a2 100644 --- a/fs/ext4/acl.c +++ b/fs/ext4/acl.c @@ -403,7 +403,7 @@ ext4_xattr_set_acl(struct dentry *dentry, const char *name, const void *value, { struct inode *inode = dentry->d_inode; handle_t *handle; - struct posix_acl *acl; + struct posix_acl *acl, *real_acl; int error, retries = 0; int update_mode = 0; umode_t mode = inode->i_mode; @@ -416,7 +416,7 @@ ext4_xattr_set_acl(struct dentry *dentry, const char *name, const void *value, return -EPERM; if (value) { - acl = posix_acl_from_xattr(&init_user_ns, value, size); + acl = real_acl = posix_acl_from_xattr(&init_user_ns, value, size); if (IS_ERR(acl)) return PTR_ERR(acl); else if (acl) { @@ -425,7 +425,7 @@ ext4_xattr_set_acl(struct dentry *dentry, const char *name, const void *value, goto release_and_out; } } else - acl = NULL; + acl = real_acl = NULL; retry: handle = ext4_journal_start(inode, EXT4_HT_XATTR, @@ -452,7 +452,7 @@ ext4_xattr_set_acl(struct dentry *dentry, const char *name, const void *value, goto retry; release_and_out: - posix_acl_release(acl); + posix_acl_release(real_acl); return error; } _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel