From e371988d3ce2d47c173940af40d3473c57a37e65 Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Tue, 7 Mar 2023 14:35:23 +0100 Subject: [PATCH] s390/ipl: add missing intersection check to ipl_report handling commit d8b9d945440d2a0f3dfdc7e964e5cccf9bc95378 upstream. 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. Cc: Fixes: 55590fd945be ("s390/ipl: read IPL report at early boot") Signed-off-by: Sven Schnelle Reviewed-by: Vasily Gorbik Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman --- arch/s390/boot/ipl_report.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/s390/boot/ipl_report.c b/arch/s390/boot/ipl_report.c index 9b14045065b6e..74b5cd2648622 100644 --- a/arch/s390/boot/ipl_report.c +++ b/arch/s390/boot/ipl_report.c @@ -57,11 +57,19 @@ repeat: 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; -- 2.39.5