[PATCH] Sync compat getdents on ia64 and parisc

[PATCH] Sync compat getdents on ia64 and parisc

[Alexey Dobriyan]

From: Alexandr Andreev <aandreev@openvz.org>

Add VERIFY_WRITE check in the beginning like compat_sys_getdents()
[EINVAL vs EFAULT on ia64.
 EFAULT on parisc if put_user() fails. --adobriyan]

Can arch maintainers look if compat_sys_getdents() is OK for them?

Signed-off-by: Alexandr Andreev <aandreev@openvz.org>
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
---

 arch/ia64/ia32/sys_ia32.c         |   10 +++++++---
 arch/parisc/kernel/sys_parisc32.c |   10 ++++++++--
 2 files changed, 15 insertions(+), 5 deletions(-)

--- a/arch/ia64/ia32/sys_ia32.c
+++ b/arch/ia64/ia32/sys_ia32.c
@@ -1267,6 +1267,10 @@ sys32_getdents (unsigned int fd, struct 
 	struct getdents32_callback buf;
 	int error;
 
+	error = -EFAULT;
+	if (!access_ok(VERIFY_WRITE, dirent, count))
+		goto out;
+
 	error = -EBADF;
 	file = fget(fd);
 	if (!file)
@@ -1283,10 +1287,10 @@ sys32_getdents (unsigned int fd, struct 
 	error = buf.error;
 	lastdirent = buf.previous;
 	if (lastdirent) {
-		error = -EINVAL;
 		if (put_user(file->f_pos, &lastdirent->d_off))
-			goto out_putf;
-		error = count - buf.count;
+			error = -EFAULT;
+		else
+			error = count - buf.count;
 	}
 
 out_putf:
--- a/arch/parisc/kernel/sys_parisc32.c
+++ b/arch/parisc/kernel/sys_parisc32.c
@@ -350,6 +350,10 @@ sys32_getdents (unsigned int fd, void __
 	struct getdents32_callback buf;
 	int error;
 
+	error = -EFAULT;
+	if (!access_ok(VERIFY_WRITE, dirent, count))
+		goto out;
+
 	error = -EBADF;
 	file = fget(fd);
 	if (!file)
@@ -366,8 +370,10 @@ sys32_getdents (unsigned int fd, void __
 	error = buf.error;
 	lastdirent = buf.previous;
 	if (lastdirent) {
-		put_user(file->f_pos, &lastdirent->d_off);
-		error = count - buf.count;
+		if (put_user(file->f_pos, &lastdirent->d_off))
+			error = -EFAULT;
+		else
+			error = count - buf.count;
 	}
 
 out_putf: