From: Ilya Leoshkevich <[email protected]> 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: [email protected] Fixes: 7b7a3366e142 ("linux-user: Use walk_memory_regions for open_self_maps") Signed-off-by: Ilya Leoshkevich <[email protected]> Reviewed-by: Laurent Vivier <[email protected]> Reviewed-by: Richard Henderson <[email protected]> Message-ID: <[email protected]> Signed-off-by: Richard Henderson <[email protected]> (cherry picked from commit bbd5630a75e70a0f1bcf04de74c94aa94a145628) Signed-off-by: Michael Tokarev <[email protected]> (Mjt: context fix in linux-user/syscall.c due to missing v9.0.0-421-g59272469bd13 "user: Use get_task_state() helper") diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 2edbd1ef15..caa91c3b1d 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -8132,17 +8132,19 @@ static int open_self_maps_1(CPUArchState *env, int fd, bool smaps) { struct open_self_maps_data d = { .ts = env_cpu(env)->opaque, - .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; } -- 2.39.5
