FAILED: patch "[PATCH] s390/ipl: add missing intersection check to ipl_report" failed to apply to 5.4-stable tree

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x a52e5cdbe8016d4e3e6322fd93d71afddb9a5af9
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '[email protected]' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

a52e5cdbe801 ("s390/ipl: add missing intersection check to ipl_report handling") 84733284f67b ("s390/boot: introduce boot data 'initrd_data'")
9f744abb4639 ("s390/boot: replace magic string check with a bootdata flag") 73045a08cf55 ("s390: unify identity mapping limits handling")
d7e7fbba67a3 ("s390/early: rewrite program parameter setup in C")
0c4ec024a481 ("s390/kasan: move memory needs estimation into a function") 92bca2fe61f5 ("s390/kasan: avoid confusing naming")
90178c190079 ("s390/mm: let vmalloc area size depend on physical memory size") a3453d923ece ("s390/kasan: remove 3-level paging support")
847d4287a0c6 ("Merge tag 's390-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From a52e5cdbe8016d4e3e6322fd93d71afddb9a5af9 Mon Sep 17 00:00:00 2001
From: Sven Schnelle <[email protected]>
Date: Tue, 7 Mar 2023 14:35:23 +0100
Subject: [PATCH] s390/ipl: add missing intersection check to ipl_report
handling

The code which handles the ipl report is searching for a free location in memory where it could copy the component and certificate entries to. It checks for intersection between the sections required for the kernel and the component/certificate data area, but fails to check whether the data structures linking these data areas together intersect.

This might cause the iplreport copy code to overwrite the iplreport itself. Fix this by adding two addtional intersection checks.

index 9b14045065b6..74b5cd264862 100644
@@ -57,11 +57,19 @@ static unsigned long find_bootdata_space(struct ipl_rb_components *comps,
 	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && initrd_data.start && initrd_data.size &&
 	    intersects(initrd_data.start, initrd_data.size, safe_addr, size))
 		safe_addr = initrd_data.start + initrd_data.size;
+	if (intersects(safe_addr, size, (unsigned long)comps, comps->len)) {
+		safe_addr = (unsigned long)comps + comps->len;
+		goto repeat;
+	}
 	for_each_rb_entry(comp, comps)
 		if (intersects(safe_addr, size, comp->addr, comp->len)) {
 			safe_addr = comp->addr + comp->len;
 			goto repeat;
 		}
+	if (intersects(safe_addr, size, (unsigned long)certs, certs->len)) {
+		safe_addr = (unsigned long)certs + certs->len;
+		goto repeat;
+	}
 	for_each_rb_entry(cert, certs)
 		if (intersects(safe_addr, size, cert->addr, cert->len)) {
 			safe_addr = cert->addr + cert->len;

The code which handles the ipl report is searching for a free location in memory where it could copy the component and certificate entries to. It checks for intersection between the sections required for the kernel and the component/certificate data area, but fails to check whether the data structures linking these data areas together intersect.

This might cause the iplreport copy code to overwrite the iplreport itself. Fix this by adding two addtional intersection checks.

---
 arch/s390/boot/ipl_report.c | 8 ++++++++
 1 file changed, 8 insertions(+)

index 0b4965573656..88bacf4999c4 100644
@@ -57,11 +57,19 @@ static unsigned long find_bootdata_space(struct ipl_rb_components *comps,
 	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && INITRD_START && INITRD_SIZE &&
 	    intersects(INITRD_START, INITRD_SIZE, safe_addr, size))
 		safe_addr = INITRD_START + INITRD_SIZE;
+	if (intersects(safe_addr, size, (unsigned long)comps, comps->len)) {
+		safe_addr = (unsigned long)comps + comps->len;
+		goto repeat;
+	}
 	for_each_rb_entry(comp, comps)
 		if (intersects(safe_addr, size, comp->addr, comp->len)) {
 			safe_addr = comp->addr + comp->len;
 			goto repeat;
 		}
+	if (intersects(safe_addr, size, (unsigned long)certs, certs->len)) {
+		safe_addr = (unsigned long)certs + certs->len;
+		goto repeat;
+	}
 	for_each_rb_entry(cert, certs)
 		if (intersects(safe_addr, size, cert->addr, cert->len)) {
 			safe_addr = cert->addr + cert->len;

2.37.2