Message ID | 20210917025635.32011-2-imp@bsdimp.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | bsd-user mmap fixes | expand |
On 9/17/21 4:56 AM, Warner Losh wrote: > From: Mikaël Urankar <mikael.urankar@gmail.com> > > linux-user/mmap.c: Always zero MAP_ANONYMOUS memory in mmap_frag() Please use it as subject, "bsd-user/mmap: Always zero MAP_ANONYMOUS memory in mmap_frag()" Then describe: Similar to the equivalent linux-user commit e6deac9cf99, ... > > When mapping MAP_ANONYMOUS memory fragments, still need notice about to > set it zero, or it will cause issues. > > Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> > Reviewed-by: Laurent Vivier <laurent@vivier.eu> > Signed-off-by: Riku Voipio <riku.voipio@linaro.org> ^ These tags were for another file, not this one, please remove them. > [ bsd-user merge by Mikaël Urankar, updated for untagged by Warner Losh ] > Signed-off-by: Mikaël Urankar <mikael.urankar@gmail.com> > Signed-off-by: Warner Losh <imp@bsdimp.com> > --- > bsd-user/mmap.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/bsd-user/mmap.c b/bsd-user/mmap.c > index b40ab9045f..fc3c1480f5 100644 > --- a/bsd-user/mmap.c > +++ b/bsd-user/mmap.c > @@ -180,10 +180,12 @@ static int mmap_frag(abi_ulong real_start, > if (prot_new != (prot1 | PROT_WRITE)) > mprotect(host_start, qemu_host_page_size, prot_new); > } else { > - /* just update the protection */ > if (prot_new != prot1) { > mprotect(host_start, qemu_host_page_size, prot_new); > } > + if (prot_new & PROT_WRITE) { > + memset(g2h_untagged(start), 0, end - start); > + } > } > return 0; > } >
On Fri, Sep 17, 2021 at 9:02 AM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote: > On 9/17/21 4:56 AM, Warner Losh wrote: > > From: Mikaël Urankar <mikael.urankar@gmail.com> > > > > linux-user/mmap.c: Always zero MAP_ANONYMOUS memory in mmap_frag() > > Please use it as subject, "bsd-user/mmap: Always zero MAP_ANONYMOUS > memory in mmap_frag()" > > Then describe: > > Similar to the equivalent linux-user commit e6deac9cf99, ... > OK. I have three commits like this, so I'll go ahead and edit all three. > > > > When mapping MAP_ANONYMOUS memory fragments, still need notice about to > > set it zero, or it will cause issues. > > > > Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> > > Reviewed-by: Laurent Vivier <laurent@vivier.eu> > > Signed-off-by: Riku Voipio <riku.voipio@linaro.org> > > ^ These tags were for another file, not this one, please > remove them. > Gotcha. I wasn't completely sure what to do in this case since they describe that the work is able to be contributed so I could make a case either way. I'll remove them. Warner > > [ bsd-user merge by Mikaël Urankar, updated for untagged by Warner Losh ] > > Signed-off-by: Mikaël Urankar <mikael.urankar@gmail.com> > > Signed-off-by: Warner Losh <imp@bsdimp.com> > > --- > > bsd-user/mmap.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/bsd-user/mmap.c b/bsd-user/mmap.c > > index b40ab9045f..fc3c1480f5 100644 > > --- a/bsd-user/mmap.c > > +++ b/bsd-user/mmap.c > > @@ -180,10 +180,12 @@ static int mmap_frag(abi_ulong real_start, > > if (prot_new != (prot1 | PROT_WRITE)) > > mprotect(host_start, qemu_host_page_size, prot_new); > > } else { > > - /* just update the protection */ > > if (prot_new != prot1) { > > mprotect(host_start, qemu_host_page_size, prot_new); > > } > > + if (prot_new & PROT_WRITE) { > > + memset(g2h_untagged(start), 0, end - start); > > + } > > } > > return 0; > > } > > > >
diff --git a/bsd-user/mmap.c b/bsd-user/mmap.c index b40ab9045f..fc3c1480f5 100644 --- a/bsd-user/mmap.c +++ b/bsd-user/mmap.c @@ -180,10 +180,12 @@ static int mmap_frag(abi_ulong real_start, if (prot_new != (prot1 | PROT_WRITE)) mprotect(host_start, qemu_host_page_size, prot_new); } else { - /* just update the protection */ if (prot_new != prot1) { mprotect(host_start, qemu_host_page_size, prot_new); } + if (prot_new & PROT_WRITE) { + memset(g2h_untagged(start), 0, end - start); + } } return 0; }