On Mon, May 18, 2020 at 1:40 PM Alexander Gordeev agordeev@linux.ibm.com wrote:
Commit 2d6261583be0 ("lib: rework bitmap_parse()") does not take into account order of halfwords on 64-bit big endian architectures.
Thanks for report and the patch!
Did it work before? Can we have a test case for that that we will see the failure?
Fixes: 2d6261583be0 ("lib: rework bitmap_parse()") Cc: stable@vger.kernel.org Cc: Yury Norov yury.norov@gmail.com Cc: Andy Shevchenko andriy.shevchenko@linux.intel.com Cc: Amritha Nambiar amritha.nambiar@intel.com Cc: Arnaldo Carvalho de Melo acme@redhat.com Cc: Chris Wilson chris@chris-wilson.co.uk Cc: Kees Cook keescook@chromium.org Cc: Matthew Wilcox willy@infradead.org Cc: Miklos Szeredi mszeredi@redhat.com Cc: Rasmus Villemoes linux@rasmusvillemoes.dk Cc: Steffen Klassert steffen.klassert@secunet.com Cc: "Tobin C . Harding" tobin@kernel.org Cc: Vineet Gupta vineet.gupta1@synopsys.com Cc: Will Deacon will.deacon@arm.com Cc: Willem de Bruijn willemb@google.com Signed-off-by: Alexander Gordeev agordeev@linux.ibm.com
lib/bitmap.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-)
diff --git a/lib/bitmap.c b/lib/bitmap.c index 89260aa..a725e46 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -717,6 +717,19 @@ static const char *bitmap_get_x32_reverse(const char *start, return end; }
+#if defined(__BIG_ENDIAN) && defined(CONFIG_64BIT) +static void save_x32_chunk(unsigned long *maskp, u32 chunk, int chunk_idx) +{
maskp += (chunk_idx / 2);((u32 *)maskp)[(chunk_idx & 1) ^ 1] = chunk;+} +#else +static void save_x32_chunk(unsigned long *maskp, u32 chunk, int chunk_idx) +{
((u32 *)maskp)[chunk_idx] = chunk;+} +#endif
/**
- bitmap_parse - convert an ASCII hex string into a bitmap.
- @start: pointer to buffer containing string.
@@ -738,7 +751,8 @@ int bitmap_parse(const char *start, unsigned int buflen, { const char *end = strnchrnul(start, buflen, '\n') - 1; int chunks = BITS_TO_U32(nmaskbits);
u32 *bitmap = (u32 *)maskp;
int chunk_idx = 0;u32 chunk; int unset_bit; while (1) {@@ -749,9 +763,11 @@ int bitmap_parse(const char *start, unsigned int buflen, if (!chunks--) return -EOVERFLOW;
end = bitmap_get_x32_reverse(start, end, bitmap++);
end = bitmap_get_x32_reverse(start, end, &chunk); if (IS_ERR(end)) return PTR_ERR(end);save_x32_chunk(maskp, chunk, chunk_idx++); } unset_bit = (BITS_TO_U32(nmaskbits) - chunks) * 32;-- 1.8.3.1