Revision 633593a808980f82d251d0ca89730d8bb8b0220c authored by Eric Dumazet on 10 March 2022, 00:11:45 UTC, committed by Jakub Kicinski on 10 March 2022, 22:46:42 UTC
syzbot reported a kernel infoleak [1] of 4 bytes.

After analysis, it turned out r->idiag_expires is not initialized
if inet_sctp_diag_fill() calls inet_diag_msg_common_fill()

Make sure to clear idiag_timer/idiag_retrans/idiag_expires
and let inet_diag_msg_sctpasoc_fill() fill them again if needed.

[1]

BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:121 [inline]
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:154 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x6ef/0x25a0 lib/iov_iter.c:668
 instrument_copy_to_user include/linux/instrumented.h:121 [inline]
 copyout lib/iov_iter.c:154 [inline]
 _copy_to_iter+0x6ef/0x25a0 lib/iov_iter.c:668
 copy_to_iter include/linux/uio.h:162 [inline]
 simple_copy_to_iter+0xf3/0x140 net/core/datagram.c:519
 __skb_datagram_iter+0x2d5/0x11b0 net/core/datagram.c:425
 skb_copy_datagram_iter+0xdc/0x270 net/core/datagram.c:533
 skb_copy_datagram_msg include/linux/skbuff.h:3696 [inline]
 netlink_recvmsg+0x669/0x1c80 net/netlink/af_netlink.c:1977
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 __sys_recvfrom+0x795/0xa10 net/socket.c:2097
 __do_sys_recvfrom net/socket.c:2115 [inline]
 __se_sys_recvfrom net/socket.c:2111 [inline]
 __x64_sys_recvfrom+0x19d/0x210 net/socket.c:2111
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:737 [inline]
 slab_alloc_node mm/slub.c:3247 [inline]
 __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4975
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 __alloc_skb+0x545/0xf90 net/core/skbuff.c:426
 alloc_skb include/linux/skbuff.h:1158 [inline]
 netlink_dump+0x3e5/0x16c0 net/netlink/af_netlink.c:2248
 __netlink_dump_start+0xcf8/0xe90 net/netlink/af_netlink.c:2373
 netlink_dump_start include/linux/netlink.h:254 [inline]
 inet_diag_handler_cmd+0x2e7/0x400 net/ipv4/inet_diag.c:1341
 sock_diag_rcv_msg+0x24a/0x620
 netlink_rcv_skb+0x40c/0x7e0 net/netlink/af_netlink.c:2494
 sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:277
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x1093/0x1360 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x14d9/0x1720 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 sock_write_iter+0x594/0x690 net/socket.c:1061
 do_iter_readv_writev+0xa7f/0xc70
 do_iter_write+0x52c/0x1500 fs/read_write.c:851
 vfs_writev fs/read_write.c:924 [inline]
 do_writev+0x645/0xe00 fs/read_write.c:967
 __do_sys_writev fs/read_write.c:1040 [inline]
 __se_sys_writev fs/read_write.c:1037 [inline]
 __x64_sys_writev+0xe5/0x120 fs/read_write.c:1037
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Bytes 68-71 of 2508 are uninitialized
Memory access of size 2508 starts at ffff888114f9b000
Data copied to user address 00007f7fe09ff2e0

CPU: 1 PID: 3478 Comm: syz-executor306 Not tainted 5.17.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: 8f840e47f190 ("sctp: add the sctp_diag.c file")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Link: https://lore.kernel.org/r/20220310001145.297371-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
1 parent 26183cf
Raw File
Makefile.package
# SPDX-License-Identifier: GPL-2.0-only
# Makefile for the different targets used to generate full packages of a kernel

include $(srctree)/scripts/Kbuild.include

# RPM target
# ---------------------------------------------------------------------------
# The rpm target generates two rpm files:
# /usr/src/packages/SRPMS/kernel-2.6.7rc2-1.src.rpm
# /usr/src/packages/RPMS/i386/kernel-2.6.7rc2-1.<arch>.rpm
# The src.rpm files includes all source for the kernel being built
# The <arch>.rpm includes kernel configuration, modules etc.
#
# Process to create the rpm files
# a) clean the kernel
# b) Generate .spec file
# c) Build a tar ball, using symlink to make kernel version
#    first entry in the path
# d) and pack the result to a tar.gz file
# e) generate the rpm files, based on kernel.spec
# - Use /. to avoid tar packing just the symlink

# Note that the rpm-pkg target cannot be used with KBUILD_OUTPUT,
# but the binrpm-pkg target can; for some reason O= gets ignored.

# Remove hyphens since they have special meaning in RPM filenames
KERNELPATH := kernel-$(subst -,_,$(KERNELRELEASE))
KDEB_SOURCENAME ?= linux-upstream
KBUILD_PKG_ROOTCMD ?="fakeroot -u"
export KDEB_SOURCENAME
# Include only those top-level files that are needed by make, plus the GPL copy
TAR_CONTENT := $(KBUILD_ALLDIRS) .config .scmversion Makefile \
               Kbuild Kconfig COPYING $(wildcard localversion*)
MKSPEC     := $(srctree)/scripts/package/mkspec

quiet_cmd_src_tar = TAR     $(2).tar.gz
      cmd_src_tar = \
if test "$(objtree)" != "$(srctree)"; then \
	echo >&2; \
	echo >&2 "  ERROR:"; \
	echo >&2 "  Building source tarball is not possible outside the"; \
	echo >&2 "  kernel source tree. Don't set KBUILD_OUTPUT, or use the"; \
	echo >&2 "  binrpm-pkg or bindeb-pkg target instead."; \
	echo >&2; \
	false; \
fi ; \
$(srctree)/scripts/setlocalversion --save-scmversion; \
tar -I $(KGZIP) -c $(RCS_TAR_IGNORE) -f $(2).tar.gz \
	--transform 's:^:$(2)/:S' $(TAR_CONTENT) $(3); \
rm -f $(objtree)/.scmversion

# rpm-pkg
# ---------------------------------------------------------------------------
PHONY += rpm-pkg
rpm-pkg:
	$(MAKE) clean
	$(CONFIG_SHELL) $(MKSPEC) >$(objtree)/kernel.spec
	$(call cmd,src_tar,$(KERNELPATH),kernel.spec)
	+rpmbuild $(RPMOPTS) --target $(UTS_MACHINE) -ta $(KERNELPATH).tar.gz \
	--define='_smp_mflags %{nil}'

# binrpm-pkg
# ---------------------------------------------------------------------------
PHONY += binrpm-pkg
binrpm-pkg:
	$(MAKE) -f $(srctree)/Makefile
	$(CONFIG_SHELL) $(MKSPEC) prebuilt > $(objtree)/binkernel.spec
	+rpmbuild $(RPMOPTS) --define "_builddir $(objtree)" --target \
		$(UTS_MACHINE) -bb $(objtree)/binkernel.spec

PHONY += deb-pkg
deb-pkg:
	$(MAKE) clean
	$(CONFIG_SHELL) $(srctree)/scripts/package/mkdebian
	$(call cmd,src_tar,$(KDEB_SOURCENAME))
	origversion=$$(dpkg-parsechangelog -SVersion |sed 's/-[^-]*$$//');\
		mv $(KDEB_SOURCENAME).tar.gz ../$(KDEB_SOURCENAME)_$${origversion}.orig.tar.gz
	+dpkg-buildpackage -r$(KBUILD_PKG_ROOTCMD) -a$$(cat debian/arch) $(DPKG_FLAGS) -i.git -us -uc

PHONY += bindeb-pkg
bindeb-pkg:
	$(CONFIG_SHELL) $(srctree)/scripts/package/mkdebian
	+dpkg-buildpackage -r$(KBUILD_PKG_ROOTCMD) -a$$(cat debian/arch) $(DPKG_FLAGS) -b -nc -uc

PHONY += intdeb-pkg
intdeb-pkg:
	+$(CONFIG_SHELL) $(srctree)/scripts/package/builddeb

# snap-pkg
# ---------------------------------------------------------------------------
PHONY += snap-pkg
snap-pkg:
	rm -rf $(objtree)/snap
	mkdir $(objtree)/snap
	$(MAKE) clean
	$(call cmd,src_tar,$(KERNELPATH))
	sed "s@KERNELRELEASE@$(KERNELRELEASE)@; \
		s@SRCTREE@$(shell realpath $(KERNELPATH).tar.gz)@" \
		$(srctree)/scripts/package/snapcraft.template > \
		$(objtree)/snap/snapcraft.yaml
	cd $(objtree)/snap && \
	snapcraft --target-arch=$(UTS_MACHINE)

# tarball targets
# ---------------------------------------------------------------------------
tar-pkgs := dir-pkg tar-pkg targz-pkg tarbz2-pkg tarxz-pkg tarzst-pkg
PHONY += $(tar-pkgs)
$(tar-pkgs):
	$(MAKE) -f $(srctree)/Makefile
	+$(CONFIG_SHELL) $(srctree)/scripts/package/buildtar $@

# perf-pkg - generate a source tarball with perf source
# ---------------------------------------------------------------------------

perf-tar=perf-$(KERNELVERSION)

quiet_cmd_perf_tar = TAR
      cmd_perf_tar = \
git --git-dir=$(srctree)/.git archive --prefix=$(perf-tar)/         \
	HEAD^{tree} $$(cd $(srctree);                               \
		       echo $$(cat tools/perf/MANIFEST)) \
	-o $(perf-tar).tar;                                         \
mkdir -p $(perf-tar);                                               \
git --git-dir=$(srctree)/.git rev-parse HEAD > $(perf-tar)/HEAD;    \
(cd $(srctree)/tools/perf;                                          \
util/PERF-VERSION-GEN $(CURDIR)/$(perf-tar)/);              \
tar rf $(perf-tar).tar $(perf-tar)/HEAD $(perf-tar)/PERF-VERSION-FILE; \
rm -r $(perf-tar);                                                  \
$(if $(findstring tar-src,$@),,                                     \
$(if $(findstring bz2,$@),$(KBZIP2),                                 \
$(if $(findstring gz,$@),$(KGZIP),                                  \
$(if $(findstring xz,$@),$(XZ),                                     \
$(if $(findstring zst,$@),$(ZSTD),                                  \
$(error unknown target $@)))))                                      \
	-f -9 $(perf-tar).tar)

perf-tar-pkgs := perf-tar-src-pkg perf-targz-src-pkg perf-tarbz2-src-pkg \
		 perf-tarxz-src-pkg perf-tarzst-src-pkg
PHONY += $(perf-tar-pkgs)
$(perf-tar-pkgs):
	$(call cmd,perf_tar)

# Help text displayed when executing 'make help'
# ---------------------------------------------------------------------------
PHONY += help
help:
	@echo '  rpm-pkg             - Build both source and binary RPM kernel packages'
	@echo '  binrpm-pkg          - Build only the binary kernel RPM package'
	@echo '  deb-pkg             - Build both source and binary deb kernel packages'
	@echo '  bindeb-pkg          - Build only the binary kernel deb package'
	@echo '  snap-pkg            - Build only the binary kernel snap package'
	@echo '                        (will connect to external hosts)'
	@echo '  dir-pkg             - Build the kernel as a plain directory structure'
	@echo '  tar-pkg             - Build the kernel as an uncompressed tarball'
	@echo '  targz-pkg           - Build the kernel as a gzip compressed tarball'
	@echo '  tarbz2-pkg          - Build the kernel as a bzip2 compressed tarball'
	@echo '  tarxz-pkg           - Build the kernel as a xz compressed tarball'
	@echo '  tarzst-pkg          - Build the kernel as a zstd compressed tarball'
	@echo '  perf-tar-src-pkg    - Build $(perf-tar).tar source tarball'
	@echo '  perf-targz-src-pkg  - Build $(perf-tar).tar.gz source tarball'
	@echo '  perf-tarbz2-src-pkg - Build $(perf-tar).tar.bz2 source tarball'
	@echo '  perf-tarxz-src-pkg  - Build $(perf-tar).tar.xz source tarball'
	@echo '  perf-tarzst-src-pkg - Build $(perf-tar).tar.zst source tarball'

.PHONY: $(PHONY)
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