diff options
author | Yury Norov <yury.norov@gmail.com> | 2019-05-14 15:43:11 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-14 19:52:49 -0700 |
commit | 281327c99bcaa8dbd4fe49cc32178dc59b0e61b8 (patch) | |
tree | 0797d824ee9bf5afb96eaa6b098601d2e90fbc11 /lib/bitmap.c | |
parent | 9f6158946987a5ce3f16da097d18f240a89db417 (diff) | |
download | linux-281327c99bcaa8dbd4fe49cc32178dc59b0e61b8.tar.gz |
lib: make bitmap_parselist_user() a wrapper on bitmap_parselist()
Patch series "lib: rework bitmap_parselist and tests", v5. bitmap_parselist has been evolved from a pretty simple idea for long and now lacks for refactoring. It is not structured, has nested loops and a set of opaque-named variables. Things are more complicated because bitmap_parselist() is a part of user interface, and its behavior should not change. In this patchset - bitmap_parselist_user() made a wrapper on bitmap_parselist(); - bitmap_parselist() reworked (patch 2); - time measurement in test_bitmap_parselist switched to ktime_get (patch 3); - new tests introduced (patch 4), and - bitmap_parselist_user() testing enabled with the same testset as bitmap_parselist() (patch 5). This patch (of 5): Currently we parse user data byte after byte which leads to overcomplification of parsing algorithm. The only user of bitmap_parselist_user() is not performance-critical, and so we can duplicate user data to kernel buffer and simply call bitmap_parselist(). This rework lets us unify and simplify bitmap_parselist() and bitmap_parselist_user(), which is done in the following patch. Link: http://lkml.kernel.org/r/20190405173211.11373-2-ynorov@marvell.com Signed-off-by: Yury Norov <ynorov@marvell.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Mike Travis <travis@sgi.com> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/bitmap.c')
-rw-r--r-- | lib/bitmap.c | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c index 3f3b8051f342..c63ddd06a5da 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -632,19 +632,22 @@ EXPORT_SYMBOL(bitmap_parselist); * @nmaskbits: size of bitmap, in bits. * * Wrapper for bitmap_parselist(), providing it with user buffer. - * - * We cannot have this as an inline function in bitmap.h because it needs - * linux/uaccess.h to get the access_ok() declaration and this causes - * cyclic dependencies. */ int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen, unsigned long *maskp, int nmaskbits) { - if (!access_ok(ubuf, ulen)) - return -EFAULT; - return __bitmap_parselist((const char __force *)ubuf, - ulen, 1, maskp, nmaskbits); + char *buf; + int ret; + + buf = memdup_user_nul(ubuf, ulen); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + ret = bitmap_parselist(buf, maskp, nmaskbits); + + kfree(buf); + return ret; } EXPORT_SYMBOL(bitmap_parselist_user); |