| Message ID | 20220126212559.1936290-3-venture@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | linux-user: check read permissions before how | expand |
Le 26/01/2022 à 22:25, Patrick Venture a écrit : > Linux kernel now checks the read permissions before validating `how` > > Suggested-by: Laurent Vivier <laurent@vivier.eu> > Signed-off-by: Patrick Venture <venture@google.com> > Reviewed-by: Laurent Vivier <laurent@vivier.eu> > --- > linux-user/syscall.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/linux-user/syscall.c b/linux-user/syscall.c > index 34bd819e38..210483d4e4 100644 > --- a/linux-user/syscall.c > +++ b/linux-user/syscall.c > @@ -9465,6 +9465,13 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, > int how; > > if (arg2) { > + p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1)); > + if (!p) { > + return -TARGET_EFAULT; > + } > + target_to_host_old_sigset(&set, p); > + unlock_user(p, arg2, 0); > + set_ptr = &set; > switch (arg1) { > case TARGET_SIG_BLOCK: > how = SIG_BLOCK; > @@ -9478,11 +9485,6 @@ 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_old_sigset(&set, p); > - unlock_user(p, arg2, 0); > - set_ptr = &set; > } else { > how = 0; > set_ptr = NULL; Applied to my linux-user-for-7.0 branch. Thanks, Laurent
diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 34bd819e38..210483d4e4 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -9465,6 +9465,13 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, int how; if (arg2) { + p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1)); + if (!p) { + return -TARGET_EFAULT; + } + target_to_host_old_sigset(&set, p); + unlock_user(p, arg2, 0); + set_ptr = &set; switch (arg1) { case TARGET_SIG_BLOCK: how = SIG_BLOCK; @@ -9478,11 +9485,6 @@ 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_old_sigset(&set, p); - unlock_user(p, arg2, 0); - set_ptr = &set; } else { how = 0; set_ptr = NULL;