4.9-stable review patch. If anyone has any objections, please let me know.
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Commit 319508902600c2688e057750148487996396e9ca upstream.
Copy events to user using __copy_to_user() rather than copy members of individually with __put_user_error(). This has the benefit of disabling/enabling PAN once per event intead of once per event member.
Signed-off-by: Julien Thierry julien.thierry@arm.com Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: David A. Long dave.long@linaro.org Reviewed-by: Julien Thierry julien.thierry@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm/kernel/sys_oabi-compat.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c index 640748e27035..d844c5c9364b 100644 --- a/arch/arm/kernel/sys_oabi-compat.c +++ b/arch/arm/kernel/sys_oabi-compat.c @@ -276,6 +276,7 @@ asmlinkage long sys_oabi_epoll_wait(int epfd, int maxevents, int timeout) { struct epoll_event *kbuf; + struct oabi_epoll_event e; mm_segment_t fs; long ret, err, i;
@@ -294,8 +295,11 @@ asmlinkage long sys_oabi_epoll_wait(int epfd, set_fs(fs); err = 0; for (i = 0; i < ret; i++) { - __put_user_error(kbuf[i].events, &events->events, err); - __put_user_error(kbuf[i].data, &events->data, err); + e.events = kbuf[i].events; + e.data = kbuf[i].data; + err = __copy_to_user(events, &e, sizeof(e)); + if (err) + break; events++; } kfree(kbuf);