5.15-stable patches

added patches:
	ima-fix-out-of-bounds-read-in-xattr_verify.patch

diff --git a/queue-5.15/ima-fix-out-of-bounds-read-in-xattr_verify.patch b/queue-5.15/ima-fix-out-of-bounds-read-in-xattr_verify.patch
new file mode 100644 (file)
index 0000000..1121101
--- /dev/null
+++ b/queue-5.15/ima-fix-out-of-bounds-read-in-xattr_verify.patch
@@ -0,0 +1,59 @@
+From 5ff232d31106f45ac87c3b64e1d35a0667777797 Mon Sep 17 00:00:00 2001
+From: Lincoln Wallace <locnnil0@gmail.com>
+Date: Mon, 3 Aug 2026 10:50:21 -0300
+Subject: ima: fix out-of-bounds read in xattr_verify()
+
+From: Lincoln Wallace <locnnil0@gmail.com>
+
+commit 5ff232d31106f45ac87c3b64e1d35a0667777797 upstream.
+
+The digest-length check in xattr_verify() mixes int and size_t:
+
+       if (xattr_len - sizeof(xattr_value->type) - hash_start >=
+                       iint->ima_hash->length)
+
+sizeof() yields size_t, so the usual arithmetic conversions promote
+the whole left-hand side to unsigned 64-bit before the subtraction
+runs. For a truncated xattr this underflows instead of going negative:
+a 1-byte IMA_XATTR_DIGEST_NG xattr (xattr_len == 1, hash_start == 1)
+turns "1 - 1 - 1" into SIZE_MAX, which is trivially >= ima_hash->length.
+The check then passes and the following memcmp() reads
+iint->ima_hash->length bytes starting past the end of the buffer
+vfs_getxattr_alloc() allocated for it.
+
+Nothing upstream clamps xattr_len back into a safe range first:
+ima_get_hash_algo() only special-cases xattr_len < 2 to pick a default
+algorithm, and evm_verifyxattr() returns INTEGRITY_UNKNOWN rather than
+failing when no HMAC key is loaded, so a truncated security.ima value
+reaches the length check as-is.
+
+Rewrite the comparison so every operand stays a signed int and no
+implicit conversion to size_t can occur.
+
+Fixes: 3ea7a56067e6 ("ima: provide hash algo info in the xattr")
+Cc: stable@vger.kernel.org
+Signed-off-by: Lincoln Wallace <locnnil0@gmail.com>
+Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ security/integrity/ima/ima_appraise.c |    9 +++++++--
+ 1 file changed, 7 insertions(+), 2 deletions(-)
+
+--- a/security/integrity/ima/ima_appraise.c
++++ b/security/integrity/ima/ima_appraise.c
+@@ -254,8 +254,13 @@ static int xattr_verify(enum ima_hooks f
+               } else {
+                       set_bit(IMA_DIGSIG, &iint->atomic_flags);
+               }
+-              if (xattr_len - sizeof(xattr_value->type) - hash_start >=
+-                              iint->ima_hash->length)
++              /*
++               * Use addition, not subtraction: sizeof() forces unsigned
++               * math and a short xattr_len would wrap around, bypassing
++               * this bounds check.
++               */
++              if (xattr_len >= (int)sizeof(xattr_value->type) + hash_start +
++                              (int)iint->ima_hash->length)
+                       /*
+                        * xattr length may be longer. md5 hash in previous
+                        * version occupied 20 bytes in xattr, instead of 16

diff --git a/queue-5.15/series b/queue-5.15/series
index 087d97579b357f6c57ec78a7f2e00e308a4dd2fd..3b8f8b974211a9478cc093f92614ea526639a178 100644 (file)
--- a/queue-5.15/series
+++ b/queue-5.15/series
@@ -403,6 +403,7 @@ usb-atm-cxacru-properly-kill-rcv_urb-on-error-in-cxacru_cm.patch
 thunderbolt-icm-preserve-usb4-proxy-data-valid-bit.patch
 usb-cdnsp-fix-incorrect-endian-conversions-for-apb-timeout-register.patch
 usb-gadget-f_ncm-use-unsigned-int-for-ndp_index.patch
+ima-fix-out-of-bounds-read-in-xattr_verify.patch
 vt-add-permission-check-for-kdskbmeta-ioctl.patch
 vt-stabilize-tty-reference-in-kbd_keycode-with-tty_port_tty_get.patch
 input-evdev-fix-information-leak-in-evdev_pass_values.patch