From f7939e1eb8de872933fc2e3fa9934aa55567a541 Mon Sep 17 00:00:00 2001 From: Willy Tarreau Date: Sat, 27 Sep 2014 12:31:36 +0200 Subject: [PATCH] Revert "lzo: properly check for overruns" commit af958a38a60c7ca3d8a39c918c1baa2ff7b6b233 upstream. This reverts commit 206a81c ("lzo: properly check for overruns"). As analysed by Willem Pinckaers, this fix is still incomplete on certain rare corner cases, and it is easier to restart from the original code. Reported-by: Willem Pinckaers Cc: "Don A. Bailey" Signed-off-by: Willy Tarreau Signed-off-by: Greg Kroah-Hartman --- lib/lzo/lzo1x_decompress_safe.c | 62 +++++++++++---------------------- 1 file changed, 21 insertions(+), 41 deletions(-) diff --git a/lib/lzo/lzo1x_decompress_safe.c b/lib/lzo/lzo1x_decompress_safe.c index 8563081e8da3..569985d522d5 100644 --- a/lib/lzo/lzo1x_decompress_safe.c +++ b/lib/lzo/lzo1x_decompress_safe.c @@ -19,31 +19,11 @@ #include #include "lzodefs.h" -#define HAVE_IP(t, x) \ - (((size_t)(ip_end - ip) >= (size_t)(t + x)) && \ - (((t + x) >= t) && ((t + x) >= x))) - -#define HAVE_OP(t, x) \ - (((size_t)(op_end - op) >= (size_t)(t + x)) && \ - (((t + x) >= t) && ((t + x) >= x))) - -#define NEED_IP(t, x) \ - do { \ - if (!HAVE_IP(t, x)) \ - goto input_overrun; \ - } while (0) - -#define NEED_OP(t, x) \ - do { \ - if (!HAVE_OP(t, x)) \ - goto output_overrun; \ - } while (0) - -#define TEST_LB(m_pos) \ - do { \ - if ((m_pos) < out) \ - goto lookbehind_overrun; \ - } while (0) +#define HAVE_IP(x) ((size_t)(ip_end - ip) >= (size_t)(x)) +#define HAVE_OP(x) ((size_t)(op_end - op) >= (size_t)(x)) +#define NEED_IP(x) if (!HAVE_IP(x)) goto input_overrun +#define NEED_OP(x) if (!HAVE_OP(x)) goto output_overrun +#define TEST_LB(m_pos) if ((m_pos) < out) goto lookbehind_overrun int lzo1x_decompress_safe(const unsigned char *in, size_t in_len, unsigned char *out, size_t *out_len) @@ -78,14 +58,14 @@ int lzo1x_decompress_safe(const unsigned char *in, size_t in_len, while (unlikely(*ip == 0)) { t += 255; ip++; - NEED_IP(1, 0); + NEED_IP(1); } t += 15 + *ip++; } t += 3; copy_literal_run: #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) - if (likely(HAVE_IP(t, 15) && HAVE_OP(t, 15))) { + if (likely(HAVE_IP(t + 15) && HAVE_OP(t + 15))) { const unsigned char *ie = ip + t; unsigned char *oe = op + t; do { @@ -101,8 +81,8 @@ copy_literal_run: } else #endif { - NEED_OP(t, 0); - NEED_IP(t, 3); + NEED_OP(t); + NEED_IP(t + 3); do { *op++ = *ip++; } while (--t > 0); @@ -115,7 +95,7 @@ copy_literal_run: m_pos -= t >> 2; m_pos -= *ip++ << 2; TEST_LB(m_pos); - NEED_OP(2, 0); + NEED_OP(2); op[0] = m_pos[0]; op[1] = m_pos[1]; op += 2; @@ -139,10 +119,10 @@ copy_literal_run: while (unlikely(*ip == 0)) { t += 255; ip++; - NEED_IP(1, 0); + NEED_IP(1); } t += 31 + *ip++; - NEED_IP(2, 0); + NEED_IP(2); } m_pos = op - 1; next = get_unaligned_le16(ip); @@ -157,10 +137,10 @@ copy_literal_run: while (unlikely(*ip == 0)) { t += 255; ip++; - NEED_IP(1, 0); + NEED_IP(1); } t += 7 + *ip++; - NEED_IP(2, 0); + NEED_IP(2); } next = get_unaligned_le16(ip); ip += 2; @@ -174,7 +154,7 @@ copy_literal_run: #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) if (op - m_pos >= 8) { unsigned char *oe = op + t; - if (likely(HAVE_OP(t, 15))) { + if (likely(HAVE_OP(t + 15))) { do { COPY8(op, m_pos); op += 8; @@ -184,7 +164,7 @@ copy_literal_run: m_pos += 8; } while (op < oe); op = oe; - if (HAVE_IP(6, 0)) { + if (HAVE_IP(6)) { state = next; COPY4(op, ip); op += next; @@ -192,7 +172,7 @@ copy_literal_run: continue; } } else { - NEED_OP(t, 0); + NEED_OP(t); do { *op++ = *m_pos++; } while (op < oe); @@ -201,7 +181,7 @@ copy_literal_run: #endif { unsigned char *oe = op + t; - NEED_OP(t, 0); + NEED_OP(t); op[0] = m_pos[0]; op[1] = m_pos[1]; op += 2; @@ -214,15 +194,15 @@ match_next: state = next; t = next; #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) - if (likely(HAVE_IP(6, 0) && HAVE_OP(4, 0))) { + if (likely(HAVE_IP(6) && HAVE_OP(4))) { COPY4(op, ip); op += t; ip += t; } else #endif { - NEED_IP(t, 3); - NEED_OP(t, 0); + NEED_IP(t + 3); + NEED_OP(t); while (t > 0) { *op++ = *ip++; t--; -- 2.20.1