Fix out-of-bounds write and lack of null-termination in /proc/cpuinfo…#408
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mhansen wants to merge 2 commits into
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Fix out-of-bounds write and lack of null-termination in /proc/cpuinfo…#408mhansen wants to merge 2 commits into
mhansen wants to merge 2 commits into
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Added a reproduction test case `repro_cpuinfo` which uses a mock filesystem with an overly long 'Hardware' value to trigger the issue. The test is added to the CMake build (guarded for ARM). Marked the test as WILL_FAIL in CMake because the bug is not yet fixed in this commit. TAG=agy CONV=54bab573-9944-4cb7-9b45-7b056f7d9c47
… parser The parser for 'Hardware' and 'Revision' fields in src/arm/linux/cpuinfo.c had logic errors when handling values with length equal to or greater than the maximum buffer size. 1. If value_length == LIMIT, it would write '\0' at index LIMIT, which is out of bounds (buffer size is LIMIT). 2. If value_length > LIMIT, it would truncate to LIMIT, skip writing the null terminator, and copy LIMIT bytes, leaving the buffer non-null-terminated. Fixed by checking if value_length >= LIMIT, truncating to LIMIT - 1 if so, and always writing the null terminator at the end of the (potentially truncated) copied value. Removed the WILL_FAIL property from the repro test in CMakeLists.txt as the test now passes. TAG=agy CONV=54bab573-9944-4cb7-9b45-7b056f7d9c47
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… parser
The parser for 'Hardware' and 'Revision' fields in src/arm/linux/cpuinfo.c had logic errors when handling values with length equal to or greater than the maximum buffer size.
Fixed by checking if value_length >= LIMIT, truncating to LIMIT - 1 if so, and always writing the null terminator at the end of the (potentially truncated) copied value.
Fixes #407