osdep: Fix ROUND_UP(64-bit, 32-bit)
When using bit-wise operations that exploit the power-of-two nature of the second argument of ROUND_UP(), we still need to ensure that the mask is as wide as the first argument (done by using a ternary to force proper arithmetic promotion). Unpatched, ROUND_UP(2ULL*1024*1024*1024*1024, 512U) produces 0, instead of the intended 2TiB, because negation of an unsigned 32-bit quantity followed by widening to 64-bits does not sign-extend the mask. Broken since its introduction in commit292c8e50
(v1.5.0). Callers that passed the same width type to both macro parameters, or that had other code to ensure the first parameter's maximum runtime value did not exceed the second parameter's width, are unaffected, but I did not audit to see which (if any) existing clients of the macro could trigger incorrect behavior (I found the bug while adding a new use of the macro). While preparing the patch, checkpatch complained about poor spacing, so I also fixed that here and in the nearby DIV_ROUND_UP. CC: qemu-trivial@nongnu.org CC: qemu-stable@nongnu.org Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru> (cherry picked from commit2098b073f3
) [LY: BSC#1076775 CVE-2017-18043] Signed-off-by: Liang Yan <lyan@suse.com>
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@@ -160,11 +160,11 @@ extern int daemon(int, int);
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#define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m))
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#define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m))
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#ifndef ROUND_UP
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#ifndef ROUND_UP
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#define ROUND_UP(n,d) (((n) + (d) - 1) & -(d))
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#define ROUND_UP(n, d) (((n) + (d) - 1) & -(0 ? (n) : (d)))
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#endif
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#endif
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#ifndef DIV_ROUND_UP
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#ifndef DIV_ROUND_UP
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#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
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#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
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#endif
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#endif
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#ifndef ARRAY_SIZE
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#ifndef ARRAY_SIZE
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