diff options
| author | AKASHI Takahiro <takahiro.akashi@linaro.org> | 2013-09-24 10:00:50 +0100 |
|---|---|---|
| committer | Alex Shi <alex.shi@linaro.org> | 2014-06-09 16:15:11 +0800 |
| commit | cd875016b2e6e2a131588b8e47eb9b7acf7a58b1 (patch) | |
| tree | b64dcfd40e93e9dc7dc4dbda74402deaad09802f /arch | |
| parent | 17b540de3606cf13203bb5c993477b851bdc9485 (diff) | |
arm64: avoid multiple evaluation of ptr in get_user/put_user()
get_user() is defined as a function macro in arm64, and trace_get_user()
calls it as followed:
get_user(ch, ptr++);
Since the second parameter occurs twice in the definition, 'ptr++' is
unexpectedly evaluated twice and trace_get_user() will generate a bogus
string from user-provided one. As a result, some ftrace sysfs operations,
like "echo FUNCNAME > set_ftrace_filter," hit this case and eventually fail.
This patch fixes the issue both in get_user() and put_user().
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
[catalin.marinas@arm.com: added __user type annotation and s/optr/__p/]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 1f65c13efef69b6dc908e588f91a133641d8475c)
Signed-off-by: Alex Shi <alex.shi@linaro.org>
Conflicts:
arch/arm64/include/asm/uaccess.h
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/uaccess.h | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 008f8481da65..7ecc2b23882e 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -166,9 +166,10 @@ do { \ #define get_user(x, ptr) \ ({ \ - might_sleep(); \ - access_ok(VERIFY_READ, (ptr), sizeof(*(ptr))) ? \ - __get_user((x), (ptr)) : \ + __typeof__(*(ptr)) __user *__p = (ptr); \ + might_fault(); \ + access_ok(VERIFY_READ, __p, sizeof(*__p)) ? \ + __get_user((x), __p) : \ ((x) = 0, -EFAULT); \ }) @@ -227,9 +228,10 @@ do { \ #define put_user(x, ptr) \ ({ \ - might_sleep(); \ - access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr))) ? \ - __put_user((x), (ptr)) : \ + __typeof__(*(ptr)) __user *__p = (ptr); \ + might_fault(); \ + access_ok(VERIFY_WRITE, __p, sizeof(*__p)) ? \ + __put_user((x), __p) : \ -EFAULT; \ }) |