Skip to content

fix: Repair bad string formatting - missing args, dangerous format spec #2145

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
lgritz merged 1 commit into from
Aug 16, 2026
Merged

fix: Repair bad string formatting - missing args, dangerous format spec #2145

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion src/cmake/testing.cmake
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -342,7 +342,7 @@ macro (osl_add_all_tests)
debugnan debug-uninit
derivs derivs-muldiv-clobber
draw_string
error-dupes error-serialized
error-dupes error-malformed error-serialized
example-deformer
example-batched-deformer
exit exponential
Expand Down
2 changes: 1 addition & 1 deletion src/liboslcomp/typecheck.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1221,7 +1221,7 @@ ASTfunction_call::typecheck_printf_args(const char* format, ASTNode* arg)
&& formatchar != 's') {
errorfmt(
"{} has mismatched format string and arguments (arg {} needs %s)",
m_name);
m_name, argnum);
return false;
}
if (simpletype.basetype == TypeDesc::INT && formatchar != 'd'
Expand Down
48 changes: 39 additions & 9 deletions src/liboslexec/journal.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -12,6 +12,36 @@

OSL_NAMESPACE_BEGIN

// Version of fmtformat_to_n that is "safe" in the sense of catching
// exceptions, not crashing (!), and turning an error into an output that
// hopefully will make it easier to track down where things are going awry.
template<typename OutIt, typename... Args>
OSL_NODISCARD inline auto
fmtformat_to_n_safe(OutIt& out, size_t n, string_view fmt, Args&&... args)
{
// DOES NOT EXIST AS PUBLIC API
// return OIIO::Strutil::fmt::format_to_n(out, n, fmt, std::forward<Args>(args)...);
// So call directly into underlying fmt library OIIO is using
// TODO: Add format_to_n as a public API in OIIO
try {
#if OSL_CPLUSPLUS_VERSION >= 20 || FMT_VERSION >= 100000
std::string str = fmtformat(fmt, std::forward<Args>(args)...);
return ::fmt::format_to_n(out, n, "{}", str);
#else
return ::fmt::format_to_n(out, n,
::fmt::string_view { fmt.begin(),
fmt.length() },
std::forward<Args>(args)...);
#endif
} catch (const std::exception& e) {
return ::fmt::format_to_n(out, n,
"MIS-FORMAT: format \"{}\" threw \"{}\"", fmt,
e.what());
}
}



int
decode_message(uint64_t format_hash, int32_t arg_count,
const EncodedType* arg_types, const uint8_t* arg_values,
Expand Down Expand Up @@ -81,7 +111,7 @@ decode_message(uint64_t format_hash, int32_t arg_count,
memcpy(&arg_value, &arg_values[arg_offset],
sizeof(arg_value));
const char* arg_string = arg_value.c_str();
auto result = OSL::fmtformat_to_n(replacement_str,
auto result = fmtformat_to_n_safe(replacement_str,
rs_max_length + 1,
replacement_region,
arg_string);
Expand All @@ -91,7 +121,7 @@ decode_message(uint64_t format_hash, int32_t arg_count,
int32_t arg_value;
memcpy(&arg_value, &arg_values[arg_offset],
sizeof(arg_value));
auto result = OSL::fmtformat_to_n(replacement_str,
auto result = fmtformat_to_n_safe(replacement_str,
rs_max_length,
replacement_region,
arg_value);
Expand All @@ -101,7 +131,7 @@ decode_message(uint64_t format_hash, int32_t arg_count,
float arg_value;
memcpy(&arg_value, &arg_values[arg_offset],
sizeof(arg_value));
auto result = OSL::fmtformat_to_n(replacement_str,
auto result = fmtformat_to_n_safe(replacement_str,
rs_max_length,
replacement_region,
arg_value);
Expand All @@ -111,7 +141,7 @@ decode_message(uint64_t format_hash, int32_t arg_count,
double arg_value;
memcpy(&arg_value, &arg_values[arg_offset],
sizeof(arg_value));
auto result = OSL::fmtformat_to_n(replacement_str,
auto result = fmtformat_to_n_safe(replacement_str,
rs_max_length,
replacement_region,
arg_value);
Expand All @@ -121,7 +151,7 @@ decode_message(uint64_t format_hash, int32_t arg_count,
int64_t arg_value;
memcpy(&arg_value, &arg_values[arg_offset],
sizeof(arg_value));
auto result = OSL::fmtformat_to_n(replacement_str,
auto result = fmtformat_to_n_safe(replacement_str,
rs_max_length,
replacement_region,
arg_value);
Expand All @@ -131,7 +161,7 @@ decode_message(uint64_t format_hash, int32_t arg_count,
uint32_t arg_value;
memcpy(&arg_value, &arg_values[arg_offset],
sizeof(arg_value));
auto result = OSL::fmtformat_to_n(replacement_str,
auto result = fmtformat_to_n_safe(replacement_str,
rs_max_length,
replacement_region,
arg_value);
Expand All @@ -141,7 +171,7 @@ decode_message(uint64_t format_hash, int32_t arg_count,
uint64_t arg_value;
memcpy(&arg_value, &arg_values[arg_offset],
sizeof(arg_value));
auto result = OSL::fmtformat_to_n(replacement_str,
auto result = fmtformat_to_n_safe(replacement_str,
rs_max_length,
replacement_region,
arg_value);
Expand All @@ -152,7 +182,7 @@ decode_message(uint64_t format_hash, int32_t arg_count,
const void* arg_value;
memcpy(&arg_value, &arg_values[arg_offset],
sizeof(arg_value));
auto result = OSL::fmtformat_to_n(replacement_str,
auto result = fmtformat_to_n_safe(replacement_str,
rs_max_length,
replacement_region,
arg_value);
Expand All @@ -163,7 +193,7 @@ decode_message(uint64_t format_hash, int32_t arg_count,
OSL::TypeDesc arg_value;
memcpy(&arg_value, &arg_values[arg_offset],
sizeof(arg_value));
auto result = OSL::fmtformat_to_n(replacement_str,
auto result = fmtformat_to_n_safe(replacement_str,
rs_max_length,
replacement_region,
arg_value);
Expand Down
8 changes: 4 additions & 4 deletions src/liboslexec/rendservices.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -206,7 +206,7 @@ RendererServices::errorfmt(OSL::ShaderGlobals* sg,
OSL::decode_message(fmt_specification.hash(), arg_count, arg_types,
arg_values, message);
ShadingContext* ctx = (ShadingContext*)((ShaderGlobals*)sg)->context;
ctx->errorfmt(message.c_str());
ctx->errorfmt("{}", message);
}


Expand All @@ -221,7 +221,7 @@ RendererServices::warningfmt(OSL::ShaderGlobals* sg,
std::string message;
OSL::decode_message(fmt_specification.hash(), arg_count, arg_types,
arg_values, message);
ctx->warningfmt(message.c_str());
ctx->warningfmt("{}", message);
}
}

Expand All @@ -236,7 +236,7 @@ RendererServices::printfmt(OSL::ShaderGlobals* sg,
OSL::decode_message(fmt_specification.hash(), arg_count, arg_types,
arg_values, message);
ShadingContext* ctx = (ShadingContext*)((ShaderGlobals*)sg)->context;
ctx->messagefmt(message.c_str());
ctx->messagefmt("{}", message);
}


Expand All @@ -254,7 +254,7 @@ RendererServices::filefmt(OSL::ShaderGlobals* sg,
// the message with the filename and hand it to the current error handler.
auto file_message = OSL::fmtformat("{}:{}", filename_hash, message);
ShadingContext* ctx = (ShadingContext*)((ShaderGlobals*)sg)->context;
ctx->messagefmt(file_message.c_str());
ctx->messagefmt("{}", file_message);
}


Expand Down
Empty file added testsuite/error-malformed/BATCHED
View file
Open in desktop
Empty file.
7 changes: 7 additions & 0 deletions testsuite/error-malformed/ref/out.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,7 @@
Compiled test.osl -> test.oso

Output Cout to out.tif
ERROR: [RendererServices::texture] Could not open file: {:d}.tif: No such file or directory
Printing {:f}
ERROR: Shader error [test]: Weird error: {:f}

8 changes: 8 additions & 0 deletions testsuite/error-malformed/run.py
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,8 @@
#!/usr/bin/env python

# Copyright Contributors to the Open Shading Language project.
# SPDX-License-Identifier: BSD-3-Clause
# https://github.com/AcademySoftwareFoundation/OpenShadingLanguage

command += testshade("-g 1 1 --center -od uint8 -o Cout out.tif test")
outputs = [ "out.txt" ]
16 changes: 16 additions & 0 deletions testsuite/error-malformed/test.osl
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,16 @@
// Copyright Contributors to the Open Shading Language project.
// SPDX-License-Identifier: BSD-3-Clause
// https://github.com/AcademySoftwareFoundation/OpenShadingLanguage

shader
test (output color Cout = 0)
{
// Regression test: nonsensical filename that seems to contain formatting
// specifications.
string filename = (u < 2.0) ? "{:d}.tif" : "../common/textures/mandrill.tif";
Cout = texture (filename, u, v);

// For good measure, also test print and error with a bad string.
printf("Printing {:f}\n");
error("Weird error: {:f}\n");
}
Loading