Blame SOURCES/CVE-2021-4028.patch

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From 44d6b1169915913fae640dada5ed931dffff6772 Mon Sep 17 00:00:00 2001
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From: "C. Erastus Toe" <ctoe@redhat.com>
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Date: Fri, 18 Feb 2022 01:09:25 -0500
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Subject: [KPATCH CVE-2021-4028] kpatch fixes for CVE-2021-4028
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Kernels:
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3.10.0-1160.21.1.el7
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3.10.0-1160.24.1.el7
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3.10.0-1160.25.1.el7
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3.10.0-1160.31.1.el7
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3.10.0-1160.36.2.el7
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3.10.0-1160.41.1.el7
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3.10.0-1160.42.2.el7
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3.10.0-1160.45.1.el7
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3.10.0-1160.49.1.el7
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3.10.0-1160.53.1.el7
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Changes since last build:
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arches: x86_64 ppc64le
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cma.o: changed function: rdma_listen
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---------------------------
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Kpatch-MR: https://gitlab.com/redhat/prdsc/rhel/src/kpatch/rhel-7/-/merge_requests/25
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Approved-by: Joe Lawrence (@joe.lawrence)
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Modifications: none
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commit 00225da7d36440d257a98004ee2e7f288486245b
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Author: Kamal Heib <kheib@redhat.com>
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Date:   Sun Jan 16 11:38:26 2022 +0200
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    RDMA/cma: Do not change route.addr.src_addr.ss_family
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    Bugzilla: http://bugzilla.redhat.com/2032075
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    CVE: CVE-2021-4028
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    Conflicts:
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    The conditional statement to verify RDMA_CM_IDLE state is a
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    little bit different from the upstream to 7.9.z source. The commit
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    732d41c545bb (RDMA/cma: Make the locking for automatic state transition
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    more clear) is missing from 7.9.z. So, the context has been modified.
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    commit bc0bdc5afaa740d782fbf936aaeebd65e5c2921d
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    Author: Jason Gunthorpe <jgg@nvidia.com>
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    Date:   Wed Sep 15 17:21:43 2021 -0300
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        RDMA/cma: Do not change route.addr.src_addr.ss_family
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        If the state is not idle then rdma_bind_addr() will immediately fail and
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        no change to global state should happen.
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        For instance if the state is already RDMA_CM_LISTEN then this will corrupt
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        the src_addr and would cause the test in cma_cancel_operation():
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                        if (cma_any_addr(cma_src_addr(id_priv)) && !id_priv->cma_dev)
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        To view a mangled src_addr, eg with a IPv6 loopback address but an IPv4
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        family, failing the test.
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        This would manifest as this trace from syzkaller:
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          BUG: KASAN: use-after-free in __list_add_valid+0x93/0xa0 lib/list_debug.c:26
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          Read of size 8 at addr ffff8881546491e0 by task syz-executor.1/32204
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          CPU: 1 PID: 32204 Comm: syz-executor.1 Not tainted 5.12.0-rc8-syzkaller #0
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          Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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          Call Trace:
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           __dump_stack lib/dump_stack.c:79 [inline]
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           dump_stack+0x141/0x1d7 lib/dump_stack.c:120
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           print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232
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           __kasan_report mm/kasan/report.c:399 [inline]
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           kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
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           __list_add_valid+0x93/0xa0 lib/list_debug.c:26
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           __list_add include/linux/list.h:67 [inline]
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           list_add_tail include/linux/list.h:100 [inline]
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           cma_listen_on_all drivers/infiniband/core/cma.c:2557 [inline]
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           rdma_listen+0x787/0xe00 drivers/infiniband/core/cma.c:3751
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           ucma_listen+0x16a/0x210 drivers/infiniband/core/ucma.c:1102
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           ucma_write+0x259/0x350 drivers/infiniband/core/ucma.c:1732
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           vfs_write+0x28e/0xa30 fs/read_write.c:603
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           ksys_write+0x1ee/0x250 fs/read_write.c:658
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           do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
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           entry_SYSCALL_64_after_hwframe+0x44/0xae
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        Which is indicating that an rdma_id_private was destroyed without doing
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        cma_cancel_listens().
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        Instead of trying to re-use the src_addr memory to indirectly create an
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        any address build one explicitly on the stack and bind to that as any
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        other normal flow would do.
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        Link: https://lore.kernel.org/r/0-v1-9fbb33f5e201+2a-cma_listen_jgg@nvidia.com
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        Cc: stable@vger.kernel.org
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        Fixes: 732d41c545bb ("RDMA/cma: Make the locking for automatic state transition more clear")
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        Reported-by: syzbot+6bb0528b13611047209c@syzkaller.appspotmail.com
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        Tested-by: Hao Sun <sunhao.th@gmail.com>
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        Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
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        Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
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    Signed-off-by: Kamal Heib <kheib@redhat.com>
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Signed-off-by: C. Erastus Toe <ctoe@redhat.com>
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---
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 drivers/infiniband/core/cma.c | 9 +++++++--
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 1 file changed, 7 insertions(+), 2 deletions(-)
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diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
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index ec473099e445..935f3979c8e2 100644
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--- a/drivers/infiniband/core/cma.c
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+++ b/drivers/infiniband/core/cma.c
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@@ -3467,8 +3467,13 @@ int rdma_listen(struct rdma_cm_id *id, int backlog)
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 	id_priv = container_of(id, struct rdma_id_private, id);
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 	if (id_priv->state == RDMA_CM_IDLE) {
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-		id->route.addr.src_addr.ss_family = AF_INET;
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-		ret = rdma_bind_addr(id, cma_src_addr(id_priv));
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+		struct sockaddr_in any_in = {
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+			.sin_family = AF_INET,
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+			.sin_addr.s_addr = htonl(INADDR_ANY),
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+		};
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+
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+		/* For a well behaved ULP state will be RDMA_CM_IDLE */
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+		ret = rdma_bind_addr(id, (struct sockaddr *)&any_in);
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 		if (ret)
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 			return ret;
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 	}
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-- 
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2.26.3
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