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authorGreg Kroah-Hartman <gregkh@google.com>2017-07-21 09:14:57 +0200
committerGreg Kroah-Hartman <gregkh@google.com>2017-07-21 09:14:57 +0200
commit59ff2e15be118b70755d9709be67ed1b842cd5e6 (patch)
tree2947d0645123c504019680244c2315b4d728c0a5 /fs/binfmt_elf.c
parent492a6047e7b5a1383627189e8bff99ff181ef4a4 (diff)
parentece78cd779f4f306a869f217bc0236507b0fe5f5 (diff)
Merge 4.4.78 into android-4.4
Changes in 4.4.78 net_sched: fix error recovery at qdisc creation net: sched: Fix one possible panic when no destroy callback net/phy: micrel: configure intterupts after autoneg workaround ipv6: avoid unregistering inet6_dev for loopback net: dp83640: Avoid NULL pointer dereference. tcp: reset sk_rx_dst in tcp_disconnect() net: prevent sign extension in dev_get_stats() bpf: prevent leaking pointer via xadd on unpriviledged net: handle NAPI_GRO_FREE_STOLEN_HEAD case also in napi_frags_finish() ipv6: dad: don't remove dynamic addresses if link is down net: ipv6: Compare lwstate in detecting duplicate nexthops vrf: fix bug_on triggered by rx when destroying a vrf rds: tcp: use sock_create_lite() to create the accept socket brcmfmac: fix possible buffer overflow in brcmf_cfg80211_mgmt_tx() cfg80211: Define nla_policy for NL80211_ATTR_LOCAL_MESH_POWER_MODE cfg80211: Validate frequencies nested in NL80211_ATTR_SCAN_FREQUENCIES cfg80211: Check if PMKID attribute is of expected size irqchip/gic-v3: Fix out-of-bound access in gic_set_affinity parisc: Report SIGSEGV instead of SIGBUS when running out of stack parisc: use compat_sys_keyctl() parisc: DMA API: return error instead of BUG_ON for dma ops on non dma devs parisc/mm: Ensure IRQs are off in switch_mm() tools/lib/lockdep: Reduce MAX_LOCK_DEPTH to avoid overflowing lock_chain/: Depth kernel/extable.c: mark core_kernel_text notrace mm/list_lru.c: fix list_lru_count_node() to be race free fs/dcache.c: fix spin lockup issue on nlru->lock checkpatch: silence perl 5.26.0 unescaped left brace warnings binfmt_elf: use ELF_ET_DYN_BASE only for PIE arm: move ELF_ET_DYN_BASE to 4MB arm64: move ELF_ET_DYN_BASE to 4GB / 4MB powerpc: move ELF_ET_DYN_BASE to 4GB / 4MB s390: reduce ELF_ET_DYN_BASE exec: Limit arg stack to at most 75% of _STK_LIM vt: fix unchecked __put_user() in tioclinux ioctls mnt: In umount propagation reparent in a separate pass mnt: In propgate_umount handle visiting mounts in any order mnt: Make propagate_umount less slow for overlapping mount propagation trees selftests/capabilities: Fix the test_execve test tpm: Get rid of chip->pdev tpm: Provide strong locking for device removal Add "shutdown" to "struct class". tpm: Issue a TPM2_Shutdown for TPM2 devices. mm: fix overflow check in expand_upwards() crypto: talitos - Extend max key length for SHA384/512-HMAC and AEAD crypto: atmel - only treat EBUSY as transient if backlog crypto: sha1-ssse3 - Disable avx2 crypto: caam - fix signals handling sched/topology: Fix overlapping sched_group_mask sched/topology: Optimize build_group_mask() PM / wakeirq: Convert to SRCU PM / QoS: return -EINVAL for bogus strings tracing: Use SOFTIRQ_OFFSET for softirq dectection for more accurate results KVM: x86: disable MPX if host did not enable MPX XSAVE features kvm: vmx: Do not disable intercepts for BNDCFGS kvm: x86: Guest BNDCFGS requires guest MPX support kvm: vmx: Check value written to IA32_BNDCFGS kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS Linux 4.4.78 Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Diffstat (limited to 'fs/binfmt_elf.c')
-rw-r--r--fs/binfmt_elf.c59
1 files changed, 51 insertions, 8 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 6c031dd1bc4e..8a0243efd359 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -905,17 +905,60 @@ static int load_elf_binary(struct linux_binprm *bprm)
elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
vaddr = elf_ppnt->p_vaddr;
+ /*
+ * If we are loading ET_EXEC or we have already performed
+ * the ET_DYN load_addr calculations, proceed normally.
+ */
if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
elf_flags |= MAP_FIXED;
} else if (loc->elf_ex.e_type == ET_DYN) {
- /* Try and get dynamic programs out of the way of the
- * default mmap base, as well as whatever program they
- * might try to exec. This is because the brk will
- * follow the loader, and is not movable. */
- load_bias = ELF_ET_DYN_BASE - vaddr;
- if (current->flags & PF_RANDOMIZE)
- load_bias += arch_mmap_rnd();
- load_bias = ELF_PAGESTART(load_bias);
+ /*
+ * This logic is run once for the first LOAD Program
+ * Header for ET_DYN binaries to calculate the
+ * randomization (load_bias) for all the LOAD
+ * Program Headers, and to calculate the entire
+ * size of the ELF mapping (total_size). (Note that
+ * load_addr_set is set to true later once the
+ * initial mapping is performed.)
+ *
+ * There are effectively two types of ET_DYN
+ * binaries: programs (i.e. PIE: ET_DYN with INTERP)
+ * and loaders (ET_DYN without INTERP, since they
+ * _are_ the ELF interpreter). The loaders must
+ * be loaded away from programs since the program
+ * may otherwise collide with the loader (especially
+ * for ET_EXEC which does not have a randomized
+ * position). For example to handle invocations of
+ * "./ld.so someprog" to test out a new version of
+ * the loader, the subsequent program that the
+ * loader loads must avoid the loader itself, so
+ * they cannot share the same load range. Sufficient
+ * room for the brk must be allocated with the
+ * loader as well, since brk must be available with
+ * the loader.
+ *
+ * Therefore, programs are loaded offset from
+ * ELF_ET_DYN_BASE and loaders are loaded into the
+ * independently randomized mmap region (0 load_bias
+ * without MAP_FIXED).
+ */
+ if (elf_interpreter) {
+ load_bias = ELF_ET_DYN_BASE;
+ if (current->flags & PF_RANDOMIZE)
+ load_bias += arch_mmap_rnd();
+ elf_flags |= MAP_FIXED;
+ } else
+ load_bias = 0;
+
+ /*
+ * Since load_bias is used for all subsequent loading
+ * calculations, we must lower it by the first vaddr
+ * so that the remaining calculations based on the
+ * ELF vaddrs will be correctly offset. The result
+ * is then page aligned.
+ */
+ load_bias = ELF_PAGESTART(load_bias - vaddr);
+
total_size = total_mapping_size(elf_phdata,
loc->elf_ex.e_phnum);
if (!total_size) {