| Message ID | 20240813094654.306430-1-richard.henderson@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [for-9.1] linux-user: Preserve NULL hit in target_mmap subroutines | expand |
On 13/8/24 11:46, Richard Henderson wrote: > Do not pass guest_base to the host mmap instead of zero hint. > > Cc: qemu-stable@nongnu.org > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2353 > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > linux-user/mmap.c | 18 +++++++++++++++--- > 1 file changed, 15 insertions(+), 3 deletions(-) > > diff --git a/linux-user/mmap.c b/linux-user/mmap.c > index 4d09a72fad..6418e811f6 100644 > --- a/linux-user/mmap.c > +++ b/linux-user/mmap.c > @@ -560,9 +560,13 @@ static abi_long mmap_h_eq_g(abi_ulong start, abi_ulong len, > int host_prot, int flags, int page_flags, > int fd, off_t offset) > { > - void *p, *want_p = g2h_untagged(start); > + void *p, *want_p = NULL; > abi_ulong last; > > + if (start || (flags & (MAP_FIXED | MAP_FIXED_NOREPLACE))) { > + want_p = g2h_untagged(start); > + } > + > p = mmap(want_p, len, host_prot, flags, fd, offset); > if (p == MAP_FAILED) { > return -1; > @@ -610,11 +614,15 @@ static abi_long mmap_h_lt_g(abi_ulong start, abi_ulong len, int host_prot, > int mmap_flags, int page_flags, int fd, > off_t offset, int host_page_size) > { > - void *p, *want_p = g2h_untagged(start); > + void *p, *want_p = NULL; Maybe extract as static helper? void *p, *want_p = g2h_untagged_FOO(start, flags); > off_t fileend_adj = 0; > int flags = mmap_flags; > abi_ulong last, pass_last; > > + if (start || (flags & (MAP_FIXED | MAP_FIXED_NOREPLACE))) { > + want_p = g2h_untagged(start); > + } Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
diff --git a/linux-user/mmap.c b/linux-user/mmap.c index 4d09a72fad..6418e811f6 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -560,9 +560,13 @@ static abi_long mmap_h_eq_g(abi_ulong start, abi_ulong len, int host_prot, int flags, int page_flags, int fd, off_t offset) { - void *p, *want_p = g2h_untagged(start); + void *p, *want_p = NULL; abi_ulong last; + if (start || (flags & (MAP_FIXED | MAP_FIXED_NOREPLACE))) { + want_p = g2h_untagged(start); + } + p = mmap(want_p, len, host_prot, flags, fd, offset); if (p == MAP_FAILED) { return -1; @@ -610,11 +614,15 @@ static abi_long mmap_h_lt_g(abi_ulong start, abi_ulong len, int host_prot, int mmap_flags, int page_flags, int fd, off_t offset, int host_page_size) { - void *p, *want_p = g2h_untagged(start); + void *p, *want_p = NULL; off_t fileend_adj = 0; int flags = mmap_flags; abi_ulong last, pass_last; + if (start || (flags & (MAP_FIXED | MAP_FIXED_NOREPLACE))) { + want_p = g2h_untagged(start); + } + if (!(flags & MAP_ANONYMOUS)) { struct stat sb; @@ -740,12 +748,16 @@ static abi_long mmap_h_gt_g(abi_ulong start, abi_ulong len, int flags, int page_flags, int fd, off_t offset, int host_page_size) { - void *p, *want_p = g2h_untagged(start); + void *p, *want_p = NULL; off_t host_offset = offset & -host_page_size; abi_ulong last, real_start, real_last; bool misaligned_offset = false; size_t host_len; + if (start || (flags & (MAP_FIXED | MAP_FIXED_NOREPLACE))) { + want_p = g2h_untagged(start); + } + if (!(flags & (MAP_FIXED | MAP_FIXED_NOREPLACE))) { /* * Adjust the offset to something representable on the host.
Do not pass guest_base to the host mmap instead of zero hint. Cc: qemu-stable@nongnu.org Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2353 Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- linux-user/mmap.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)