From 1ba701c1d7bd94cc5a02f51652712acdcbf0875c Mon Sep 17 00:00:00 2001
From: Vincent Whitchurch <vincent.whitchurch@axis.com>
Date: Tue, 21 Jun 2022 09:15:33 +0000
Subject: [PATCH 2/5] coredump: fix segmentation fault caused by type mismatch
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crash gcore command on ARM sometimes results in segmentation fault:

    crash> gcore -v 0
    Segmentation fault (core dumped)

This is caused by type mismatch of a variable paddr in function
gcore_readmem_user() to hold a physical address, which is indicated by
the following warning message:

 libgcore/gcore_coredump.c: In function ‘gcore_readmem_user’:
 libgcore/gcore_coredump.c:85:26: warning: passing argument 2 of
 ‘uvtop_quiet’ from incompatible pointer type
 [-Wincompatible-pointer-types]

    if (!uvtop_quiet(addr, &paddr)) {
                           ^~~~~~
 libgcore/gcore_coredump.c:71:49: note: expected ‘physaddr_t *’ {aka
 ‘long long unsigned int *’} but argument is of type ‘ulong *’ {aka ‘long
 unsigned int *’}

  static int uvtop_quiet(ulong vaddr, physaddr_t *paddr);
                                      ~~~~~~~~~~~~^~~~~

On ARM, long unsigned int has 4 byte length, while physaddr_t has 8
byte length. The mismatch causes overwriting of stack variables.

Fix this by changing the type of the variable paddr to physaddr_t.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
---
 src/libgcore/gcore_coredump.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/libgcore/gcore_coredump.c b/src/libgcore/gcore_coredump.c
index c14cc116e951..424b0a40a42b 100644
--- a/src/libgcore/gcore_coredump.c
+++ b/src/libgcore/gcore_coredump.c
@@ -78,7 +78,8 @@ readswap(ulonglong pte_val, char *buf, ulong len, ulonglong vaddr)
 
 void gcore_readmem_user(ulong addr, void *buf, long size, char *type)
 {
-	ulong paddr, cnt;
+	physaddr_t paddr;
+	ulong cnt;
 	char *bufptr = buf;
 
 	while (size > 0) {
-- 
2.37.1