| Message ID | 1443461547-6397-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/arch/x86/lib/usercopy.c b/arch/x86/lib/usercopy.c index ddf9ecb53cc3..e342586db6e4 100644 --- a/arch/x86/lib/usercopy.c +++ b/arch/x86/lib/usercopy.c @@ -20,7 +20,7 @@ copy_from_user_nmi(void *to, const void __user *from, unsigned long n) unsigned long ret; if (__range_not_ok(from, n, TASK_SIZE)) - return 0; + return n; /* * Even though this function is typically called from NMI/IRQ context
This is a note to let you know that I have just added a patch titled perf/x86: Fix copy_from_user_nmi() return if range is not ok to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt18. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 7028d9235baaa3415f44c45243a9024a862da191 Mon Sep 17 00:00:00 2001 From: Yann Droneaud <ydroneaud@opteya.com> Date: Mon, 22 Jun 2015 21:38:43 +0200 Subject: perf/x86: Fix copy_from_user_nmi() return if range is not ok commit ebf2d2689de551d90965090bb991fc640a0c0d41 upstream. Commit 0a196848ca36 ("perf: Fix arch_perf_out_copy_user default"), changes copy_from_user_nmi() to return the number of remaining bytes so that it behave like copy_from_user(). Unfortunately, when the range is outside of the process memory, the return value is still the number of byte copied, eg. 0, instead of the remaining bytes. As all users of copy_from_user_nmi() were modified as part of commit 0a196848ca36, the function should be fixed to return the total number of bytes if range is not correct. Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1435001923-30986-1-git-send-email-ydroneaud@opteya.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Yann Droneaud <ydroneaud@opteya.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- arch/x86/lib/usercopy.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)