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| author | Bradley Morgan <brads@mainlining.org> | 2026-08-27 17:43:38 +0000 |
|---|---|---|
| committer | Mimi Zohar <zohar@linux.ibm.com> | 2026-09-01 22:29:08 -0400 |
| commit | 8861f6d5c0678a7c5089c7b272509fc5931b8437 (patch) | |
| tree | 38b79149a097588bccd2d7a704ee1c96628f3673 /security | |
| parent | 8e22ce504f8a332c57ca9676ab804da5ac4a1325 (diff) | |
| download | lwn-8861f6d5c0678a7c5089c7b272509fc5931b8437.tar.gz lwn-8861f6d5c0678a7c5089c7b272509fc5931b8437.zip | |
ima: Check for ERR_PTR from dentry_path() in validate_hash_algo()
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>
Diffstat (limited to 'security')
| -rw-r--r-- | security/integrity/ima/ima_appraise.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index ced2e131b061..b280488e15fc 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -748,6 +748,8 @@ 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); |