[PATCH] file descriptor leak in sys_pipe

From: Ulrich Drepper
Date: Mon May 05 2008 - 05:22:54 EST


DM <dm.n9107@xxxxxxxxx> wrote:
> I realize this code is old, but wouldn't file descriptors leak if
> copy_to_user fails?

I think you're right. The following should patch it for the remaining
C implementations which need that kind of patch.


Signed-off-by: Ulrich Drepper <drepper@xxxxxxxxxx>

diff --git a/arch/cris/kernel/sys_cris.c b/arch/cris/kernel/sys_cris.c
index 8b99841..d124066 100644
--- a/arch/cris/kernel/sys_cris.c
+++ b/arch/cris/kernel/sys_cris.c
@@ -40,8 +40,11 @@ asmlinkage int sys_pipe(unsigned long __user * fildes)
error = do_pipe(fd);
unlock_kernel();
if (!error) {
- if (copy_to_user(fildes, fd, 2*sizeof(int)))
+ if (copy_to_user(fildes, fd, 2*sizeof(int))) {
+ sys_close(fd[0]);
+ sys_close(fd[1]);
error = -EFAULT;
+ }
}
return error;
}
diff --git a/arch/m32r/kernel/sys_m32r.c b/arch/m32r/kernel/sys_m32r.c
index 6d7a80f..319c797 100644
--- a/arch/m32r/kernel/sys_m32r.c
+++ b/arch/m32r/kernel/sys_m32r.c
@@ -90,8 +90,11 @@ sys_pipe(unsigned long r0, unsigned long r1, unsigned long r2,

error = do_pipe(fd);
if (!error) {
- if (copy_to_user((void __user *)r0, fd, 2*sizeof(int)))
+ if (copy_to_user((void __user *)r0, fd, 2*sizeof(int))) {
+ sys_close(fd[0]);
+ sys_close(fd[1]);
error = -EFAULT;
+ }
}
return error;
}
diff --git a/fs/pipe.c b/fs/pipe.c
index 3499f9f..ec228bc 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -17,6 +17,7 @@
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/audit.h>
+#include <linux/syscalls.h>

#include <asm/uaccess.h>
#include <asm/ioctls.h>
@@ -1086,8 +1087,11 @@ asmlinkage long __weak sys_pipe(int __user *fildes)

error = do_pipe(fd);
if (!error) {
- if (copy_to_user(fildes, fd, sizeof(fd)))
+ if (copy_to_user(fildes, fd, sizeof(fd))) {
+ sys_close(fd[0]);
+ sys_close(fd[1]);
error = -EFAULT;
+ }
}
return error;
}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/