Le 14/10/2024 à 22:34, Ilya Leoshkevich a écrit :
If one thread modifies the mappings and another thread prints them,
a situation may occur that the printer thread sees a guest mapping
without a corresponding host mapping, leading to a crash in
open_self_maps_2().

Cc: qemu-sta...@nongnu.org
Fixes: 7b7a3366e142 ("linux-user: Use walk_memory_regions for open_self_maps")
Signed-off-by: Ilya Leoshkevich <i...@linux.ibm.com>
---
  linux-user/syscall.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 1354e756941..dd2ec0712b8 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -8151,17 +8151,19 @@ static int open_self_maps_1(CPUArchState *env, int fd, 
bool smaps)
  {
      struct open_self_maps_data d = {
          .ts = get_task_state(env_cpu(env)),
-        .host_maps = read_self_maps(),
          .fd = fd,
          .smaps = smaps
      };
+ mmap_lock();
+    d.host_maps = read_self_maps();
      if (d.host_maps) {
          walk_memory_regions(&d, open_self_maps_2);
          free_self_maps(d.host_maps);
      } else {
          walk_memory_regions(&d, open_self_maps_3);
      }
+    mmap_unlock();
      return 0;
  }

Reviewed-by: Laurent Vivier <laur...@vivier.eu>

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