diff options
| author | Shu-Chun Weng <scw@google.com> | 2022-01-26 13:25:58 -0800 |
|---|---|---|
| committer | Laurent Vivier <laurent@vivier.eu> | 2022-01-27 16:58:33 +0100 |
| commit | d3ced2a59a543b3c3fc7dee2e64ee360e9a698cd (patch) | |
| tree | ab07701577c2ccb984abf679fe640bf79920c343 /linux-user | |
| parent | 33f53ac52ab664f3d6ec34047c0ae21e32fa26b4 (diff) | |
linux-user: rt_sigprocmask, check read perms first
Linux kernel does it this way (checks read permission before validating `how`)
and the latest version of ABSL's `AddressIsReadable()` depends on this
behavior.
c.f. https://github.com/torvalds/linux/blob/9539ba4308ad5bdca6cb41c7b73cbb9f796dcdd7/kernel/signal.c#L3147
Reviewed-by: Patrick Venture <venture@google.com>
Signed-off-by: Shu-Chun Weng <scw@google.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Patrick Venture <venture@google.com>
Message-Id: <20220126212559.1936290-2-venture@google.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Diffstat (limited to 'linux-user')
| -rw-r--r-- | linux-user/syscall.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 2ca0f086db..9f8b497fa3 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -9478,6 +9478,13 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, } if (arg2) { + p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1); + if (!p) { + return -TARGET_EFAULT; + } + target_to_host_sigset(&set, p); + unlock_user(p, arg2, 0); + set_ptr = &set; switch(how) { case TARGET_SIG_BLOCK: how = SIG_BLOCK; @@ -9491,11 +9498,6 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, default: return -TARGET_EINVAL; } - if (!(p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1))) - return -TARGET_EFAULT; - target_to_host_sigset(&set, p); - unlock_user(p, arg2, 0); - set_ptr = &set; } else { how = 0; set_ptr = NULL; |