diff mbox

[v3,01/17] livepatch: Expand check for safe_for_reapply if livepatch has only .rodata.

Message ID 20170912003726.368-2-konrad.wilk@oracle.com (mailing list archive)
State New, archived
Headers show

Commit Message

Konrad Rzeszutek Wilk Sept. 12, 2017, 12:37 a.m. UTC 
If the livepatch has only .rodata sections then it is OK to also
apply/revert/apply the livepatch without having to worry about the
unforseen consequences.

See commit 98b728a7b235c67e210f67f789db5d9eb38ca00c
"livepatch: Disallow applying after an revert" for details.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
v3: New patch
---
 xen/common/livepatch.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)
diff mbox

Patch

diff --git a/xen/common/livepatch.c b/xen/common/livepatch.c
index 66d532db14..a1f54c42d3 100644
--- a/xen/common/livepatch.c
+++ b/xen/common/livepatch.c
@@ -417,9 +417,12 @@  static int move_payload(struct payload *payload, struct livepatch_elf *elf)
         }
     }
 
-    /* Only one RW section with non-zero size: .livepatch.funcs */
-    if ( rw_buf_cnt == 1 &&
-         !strcmp(elf->sec[rw_buf_sec].name, ELF_LIVEPATCH_FUNC) )
+    /*
+     * Only one RW section with non-zero size: .livepatch.funcs,
+     * or only RO sections.
+     */
+    if ( !rw_buf_cnt || (rw_buf_cnt == 1 &&
+         !strcmp(elf->sec[rw_buf_sec].name, ELF_LIVEPATCH_FUNC)) )
         payload->safe_to_reapply = true;
  out:
     xfree(offset);