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authorMarc Hartmayer <mhartmay@linux.ibm.com>2020-09-24 10:59:24 +0200
committerThomas Huth <thuth@redhat.com>2020-10-06 19:56:56 +0200
commit5f97ba0c74ccace0a4014460de9751ff3c6f454a (patch)
treee498ed54f7e6f62b652ec91043f425acb2a473fa
parent49d4388ec03fd8c7701b907a4e11c437a28f8572 (diff)
downloadfocaccia-qemu-5f97ba0c74ccace0a4014460de9751ff3c6f454a.tar.gz
focaccia-qemu-5f97ba0c74ccace0a4014460de9751ff3c6f454a.zip
pc-bios/s390-ccw: fix off-by-one error
This error takes effect when the magic value "zIPL" is located at the
end of a block. For example if s2_cur_blk = 0x7fe18000 and the magic
value "zIPL" is located at 0x7fe18ffc - 0x7fe18fff.

Fixes: ba831b25262a ("s390-ccw: read stage2 boot loader data to find menu")
Reviewed-by: Collin Walling <walling@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Message-Id: <20200924085926.21709-2-mhartmay@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[thuth: Use "<= ... - 4" instead of "< ... - 3"]
Signed-off-by: Thomas Huth <thuth@redhat.com>
-rw-r--r--pc-bios/s390-ccw/bootmap.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index 0ef6b851f3..767bb612db 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -163,7 +163,7 @@ static bool find_zipl_boot_menu_banner(int *offset)
     int i;
 
     /* Menu banner starts with "zIPL" */
-    for (i = 0; i < virtio_get_block_size() - 4; i++) {
+    for (i = 0; i <= virtio_get_block_size() - 4; i++) {
         if (magic_match(s2_cur_blk + i, ZIPL_MAGIC_EBCDIC)) {
             *offset = i;
             return true;