On 27/01/2022 09:22, Daniel Henrique Barboza wrote:
The 'taddr' variable is left unintialized, being set only inside the "while ((lev--) >= 0)" loop where we get the TCE address. The 'lev' var is an int32_t that is being initiliazed by the GETFIELD() macro, which returns an uint64_t.For a human reader this means that 'lev' will always be positive or zero. But some compilers may beg to differ. 'lev' being an int32_t can in theory be set as negative, and the "while ((lev--) >= 0)" loop might never be reached, and 'taddr' will be left unitialized. This can cause phb3_error() to use 'taddr' uninitialized down below: if ((is_write & !(tce & 2)) || ((!is_write) && !(tce & 1))) { phb3_error(phb, "TCE access fault at 0x%"PRIx64, taddr); A quick way of fixing it is to use a do/while() loop. This will keep the same semanting as the existing while() loop does and the compiler will understand that 'taddr' will be initialized at least once. Suggested-by: Matheus K. Ferst <[email protected]> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/573 Signed-off-by: Daniel Henrique Barboza <[email protected]> --- hw/pci-host/pnv_phb3.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
Reviewed-by: Matheus Ferst <[email protected]> Thanks, Matheus K. Ferst Instituto de Pesquisas ELDORADO <http://www.eldorado.org.br/> Analista de Software Aviso Legal - Disclaimer <https://www.eldorado.org.br/disclaimer.html>
