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envelope-from=36IvxYQcKCtsSBKQROBDLLDIB.9LJNBJR-ABSBIKLKDKR.LOD@flex--venture.bounces.google.com; helo=mail-vk1-xa49.google.com X-Spam_score_int: -87 X-Spam_score: -8.8 X-Spam_bar: -------- X-Spam_report: (-8.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_MED=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, PDS_HP_HELO_NORDNS=0.001, RCVD_IN_DNSWL_NONE=-0.0001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, USER_IN_DEF_DKIM_WL=-7.5 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Linux kernel now checks the read permissions before validating `how` Suggested-by: Laurent Vivier Signed-off-by: Patrick Venture Reviewed-by: Laurent Vivier --- 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;