54 lines
1.9 KiB
Diff
54 lines
1.9 KiB
Diff
From ef1675823905ff09cb5e551700a124d0133648b7 Mon Sep 17 00:00:00 2001
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From: Michal Kubecek <mkubecek@suse.cz>
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Date: Mon, 9 Nov 2020 13:30:54 +0100
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Subject: [PATCH 23/26] netlink: fix use after free in netlink_run_handler()
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Valgrind detected use after free in netlink_run_handler(): some members of
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struct nl_context are accessed after the netlink context is freed by
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netlink_done(). Use local variables to store the two flags and check them
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instead.
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Fixes: 6c19c0d559c8 ("netlink: use genetlink ops information to decide about fallback")
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Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
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(cherry picked from commit 29b38ea218bd978d1950e12cc24da98215a1eeef)
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---
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netlink/netlink.c | 10 +++++++---
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1 file changed, 7 insertions(+), 3 deletions(-)
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diff --git a/netlink/netlink.c b/netlink/netlink.c
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index 86dc1efdf5ce..2a12bb8b1759 100644
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--- a/netlink/netlink.c
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+++ b/netlink/netlink.c
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@@ -303,6 +303,7 @@ void netlink_run_handler(struct cmd_context *ctx, nl_func_t nlfunc,
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bool no_fallback)
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{
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bool wildcard = ctx->devname && !strcmp(ctx->devname, WILDCARD_DEVNAME);
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+ bool wildcard_unsupported, ioctl_fallback;
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struct nl_context *nlctx;
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const char *reason;
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int ret;
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@@ -324,14 +325,17 @@ void netlink_run_handler(struct cmd_context *ctx, nl_func_t nlfunc,
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nlctx = ctx->nlctx;
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ret = nlfunc(ctx);
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+ wildcard_unsupported = nlctx->wildcard_unsupported;
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+ ioctl_fallback = nlctx->ioctl_fallback;
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netlink_done(ctx);
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- if (no_fallback || ret != -EOPNOTSUPP || !nlctx->ioctl_fallback) {
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- if (nlctx->wildcard_unsupported)
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+
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+ if (no_fallback || ret != -EOPNOTSUPP || !ioctl_fallback) {
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+ if (wildcard_unsupported)
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fprintf(stderr, "%s\n",
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"subcommand does not support wildcard dump");
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exit(ret >= 0 ? ret : 1);
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}
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- if (nlctx->wildcard_unsupported)
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+ if (wildcard_unsupported)
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reason = "subcommand does not support wildcard dump";
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else
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reason = "kernel netlink support for subcommand missing";
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--
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2.26.2
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