From 226a8ae7f20cea17472c0232a022d7d526e660a3 Mon Sep 17 00:00:00 2001 From: Fabrice Fontaine Date: Sat, 15 Jan 2022 11:15:35 +0100 Subject: [PATCH] package/ghostscript: fix CVE-2021-45949 Ghostscript GhostPDL 9.50 through 9.54.0 has a heap-based buffer overflow in sampled_data_finish (called from sampled_data_continue and interp). Signed-off-by: Fabrice Fontaine Signed-off-by: Yann E. MORIN (cherry picked from commit c817641331431aeb6db7b487173d63dbd9c73295) Signed-off-by: Peter Korsgaard --- ...-management-in-sampled_data_continue.patch | 68 +++++++++++++++++++ package/ghostscript/ghostscript.mk | 3 + 2 files changed, 71 insertions(+) create mode 100644 package/ghostscript/0004-Bug-703902-Fix-op-stack-management-in-sampled_data_continue.patch diff --git a/package/ghostscript/0004-Bug-703902-Fix-op-stack-management-in-sampled_data_continue.patch b/package/ghostscript/0004-Bug-703902-Fix-op-stack-management-in-sampled_data_continue.patch new file mode 100644 index 0000000000..72e07df0ac --- /dev/null +++ b/package/ghostscript/0004-Bug-703902-Fix-op-stack-management-in-sampled_data_continue.patch @@ -0,0 +1,68 @@ +From 2a3129365d3bc0d4a41f107ef175920d1505d1f7 Mon Sep 17 00:00:00 2001 +From: Chris Liddell +Date: Tue, 1 Jun 2021 19:57:16 +0100 +Subject: [PATCH] Bug 703902: Fix op stack management in + sampled_data_continue() + +Replace pop() (which does no checking, and doesn't handle stack extension +blocks) with ref_stack_pop() which does do all that. + +We still use pop() in one case (it's faster), but we have to later use +ref_stack_pop() before calling sampled_data_sample() which also accesses the +op stack. + +Fixes: +https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=34675 + +[Retrieved from: +https://git.ghostscript.com/?p=ghostpdl.git;a=commit;h=2a3129365d3bc0d4a41f107ef175920d1505d1f7] +Signed-off-by: Fabrice Fontaine +--- + psi/zfsample.c | 16 ++++++++++------ + 1 file changed, 10 insertions(+), 6 deletions(-) + +diff --git a/psi/zfsample.c b/psi/zfsample.c +index 0e8e4bc8d..00cd0cfdd 100644 +--- a/psi/zfsample.c ++++ b/psi/zfsample.c +@@ -533,15 +533,19 @@ sampled_data_continue(i_ctx_t *i_ctx_p) + for (j = 0; j < bps; j++) + data_ptr[bps * i + j] = (byte)(cv >> ((bps - 1 - j) * 8)); /* MSB first */ + } +- pop(num_out); /* Move op to base of result values */ + +- /* Check if we are done collecting data. */ ++ pop(num_out); /* Move op to base of result values */ + ++ /* From here on, we have to use ref_stack_pop() rather than pop() ++ so that it handles stack extension blocks properly, before calling ++ sampled_data_sample() which also uses the op stack. ++ */ ++ /* Check if we are done collecting data. */ + if (increment_cube_indexes(params, penum->indexes)) { + if (stack_depth_adjust == 0) +- pop(O_STACK_PAD); /* Remove spare stack space */ ++ ref_stack_pop(&o_stack, O_STACK_PAD); /* Remove spare stack space */ + else +- pop(stack_depth_adjust - num_out); ++ ref_stack_pop(&o_stack, stack_depth_adjust - num_out); + /* Execute the closing procedure, if given */ + code = 0; + if (esp_finish_proc != 0) +@@ -554,11 +558,11 @@ sampled_data_continue(i_ctx_t *i_ctx_p) + if ((O_STACK_PAD - stack_depth_adjust) < 0) { + stack_depth_adjust = -(O_STACK_PAD - stack_depth_adjust); + check_op(stack_depth_adjust); +- pop(stack_depth_adjust); ++ ref_stack_pop(&o_stack, stack_depth_adjust); + } + else { + check_ostack(O_STACK_PAD - stack_depth_adjust); +- push(O_STACK_PAD - stack_depth_adjust); ++ ref_stack_push(&o_stack, O_STACK_PAD - stack_depth_adjust); + for (i=0;i