From: Bradley Morgan <brads@mainlining.org> stable inclusion from stable-6.6.157 commit 30b5c0e17dcad72b6b2f987319aa645570e6376d category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19109 CVE: CVE-2026-89989 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... ------------------------------ commit 8861f6d5c0678a7c5089c7b272509fc5931b8437 upstream. dentry_path() returns ERR_PTR(-ENAMETOOLONG) when the path exceeds the buffer. validate_hash_algo() passes the result straight to integrity_audit_msg() without checking. ERR_PTR is not NULL, so integrity_audit_message() sees a valid pointer and calls strlen() on it, which faults: BUG: unable to handle page fault for address: ffffffffffffffdc RIP: 0010:strlen+0x30/0xa0 Call Trace: audit_log_untrustedstring+0x19/0x30 integrity_audit_message+0x366/0x4f0 ima_inode_setxattr+0x512/0x5f0 Check for IS_ERR() and use NULL instead, which makes the audit message skip the name= field instead of crashing. Fixes: 4f2946aa0c45 ("IMA: introduce a new policy option func=SETXATTR_CHECK") Cc: stable@vger.kernel.org Reported-by: syzbot+5ebeb3089ea6439c37be@syzkaller.appspotmail.com Link: https://lore.kernel.org/all/6a8f89e5.1d9ded08.62e62.00bf.GAE@google.com/ Signed-off-by: Bradley Morgan <brads@mainlining.org> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lu Jialin <lujialin4@huawei.com> --- security/integrity/ima/ima_appraise.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 188f457f0e11..16437829a374 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -892,6 +892,8 @@ static int validate_hash_algo(struct dentry *dentry, return -EACCES; path = dentry_path(dentry, pathbuf, PATH_MAX); + if (IS_ERR(path)) + path = NULL; integrity_audit_msg(AUDIT_INTEGRITY_DATA, d_inode(dentry), path, "set_data", errmsg, -EACCES, 0); -- 2.34.1