When we dynamically generate a name for a configuration in get-reg-list we use strcat() to append to a buffer allocated using malloc() but we never initialise that buffer. Since malloc() offers no guarantees regarding the contents of the memory it returns this can lead to us corrupting, and likely overflowing, the buffer: vregs: PASS vregs+pmu: PASS sve: PASS sve+pmu: PASS vregs+pauth_address+pauth_generic: PASS X?vr+gspauth_addre+spauth_generi+pmu: PASS The bug is that strcat() should have been strcpy(), and that replacement would be enough to fix it, but there are other things in the function that leave something to be desired. In particular, an (incorrectly) empty config would cause an out of bounds access to c->name[-1]. Since the strcpy() call relies on c->name[0..len-1] being initialized, enforce that invariant throughout the function. Fixes: 2f9ace5d4557 ("KVM: arm64: selftests: get-reg-list: Introduce vcpu configs") Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Co-developed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org> Message-Id: <20231211-kvm-get-reg-list-str-init-v3-1-6554c71c77b1@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.
Description
Languages
C
97.6%
Assembly
1%
Shell
0.5%
Python
0.3%
Makefile
0.3%