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| author | Al Viro <viro@zeniv.linux.org.uk> | 2016-09-09 19:22:34 -0400 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2016-11-20 01:01:40 +0000 |
| commit | f5f944fb34661325716158eaafcd518e16a1f7cc (patch) | |
| tree | 4b957aee6a9ca7615453f60b6d088945f0084992 | |
| parent | f69350b23246c539a012f58b5f8242cb18a4a813 (diff) | |
| download | lwn-f5f944fb34661325716158eaafcd518e16a1f7cc.tar.gz lwn-f5f944fb34661325716158eaafcd518e16a1f7cc.zip | |
microblaze: fix copy_from_user()
commit d0cf385160c12abd109746cad1f13e3b3e8b50b8 upstream.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | arch/microblaze/include/asm/uaccess.h | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h index 072b0077abf9..36ea6fe84990 100644 --- a/arch/microblaze/include/asm/uaccess.h +++ b/arch/microblaze/include/asm/uaccess.h @@ -364,10 +364,13 @@ extern long __user_bad(void); static inline long copy_from_user(void *to, const void __user *from, unsigned long n) { + unsigned long res = n; might_sleep(); - if (access_ok(VERIFY_READ, from, n)) - return __copy_from_user(to, from, n); - return n; + if (likely(access_ok(VERIFY_READ, from, n))) + res = __copy_from_user(to, from, n); + if (unlikely(res)) + memset(to + (n - res), 0, res); + return res; } #define __copy_to_user(to, from, n) \ |