Re: [Xen-devel] [libvirt] [PATCH libvirt] libxl: avoid freeing an uninitialised bitmap
On 06/19/2015 10:54 AM, Eric Blake wrote: On 06/19/2015 10:33 AM, Ian Campbell wrote: If vm->def->cputune.nvcpupin is 0 in libxlDomainSetVcpuAffinities (as seems to be the case on arm) then the VIR_FREE after cleanup: would be operating on an uninitialised pointer in map.map. Fix this by using libxl_bitmap_init and libxl_bitmap_dispose in the appropriate places (like VIR_FREE libxl_bitmap_dispose is also s/VIR_FREE/VIR_FREE,/ idempotent, so there is no double free on exit from the loop). libxl_bitmap_dispose is slightly preferable since it also sets map.size back to 0, avoiding a potential source of confusion. This fixes the crashes we've been seeing in the Xen automated tests on ARM. I had a glance at the handful of other users of libxl_bitmap and none of them looked to have a similar issue. Signed-off-by: Ian Campbell --- src/libxl/libxl_domain.c |6 -- 1 file changed, 4 insertions(+), 2 deletions(-) ACK. Modified the commit message as suggested and pushed. Thanks! Regards, Jim ___ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
Re: [Xen-devel] [libvirt] [PATCH libvirt] libxl: avoid freeing an uninitialised bitmap
On 06/19/2015 10:33 AM, Ian Campbell wrote: > If vm->def->cputune.nvcpupin is 0 in libxlDomainSetVcpuAffinities (as > seems to be the case on arm) then the VIR_FREE after cleanup: would be > operating on an uninitialised pointer in map.map. > > Fix this by using libxl_bitmap_init and libxl_bitmap_dispose in the > appropriate places (like VIR_FREE libxl_bitmap_dispose is also s/VIR_FREE/VIR_FREE,/ > idempotent, so there is no double free on exit from the loop). > > libxl_bitmap_dispose is slightly preferable since it also sets > map.size back to 0, avoiding a potential source of confusion. > > This fixes the crashes we've been seeing in the Xen automated tests on > ARM. > > I had a glance at the handful of other users of libxl_bitmap and none > of them looked to have a similar issue. > > Signed-off-by: Ian Campbell > --- > src/libxl/libxl_domain.c |6 -- > 1 file changed, 4 insertions(+), 2 deletions(-) ACK. -- Eric Blake eblake redhat com+1-919-301-3266 Libvirt virtualization library http://libvirt.org signature.asc Description: OpenPGP digital signature ___ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
