From 3aefee3ec01e607529a9918e2978f365c5c3b5e9 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Tue, 13 Aug 2024 16:33:58 +1000 Subject: linux-user: Preserve NULL hit in target_mmap subroutines 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 --- 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; 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. -- cgit v1.2.3