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authorEric Dumazet <edumazet@google.com>2019-05-22 16:51:22 -0700
committerDavid S. Miller <davem@davemloft.net>2019-05-22 18:04:17 -0700
commit3580d04aa674383c42de7b635d28e52a1e5bc72c (patch)
tree4e07b0727a1d50c20c778e7dee69f4d19c1d63e5 /net/ipv4/igmp.c
parentdb51a73282bbed61209b1c071e0a4f62e8918b0a (diff)
ipv4/igmp: fix another memory leak in igmpv3_del_delrec()
syzbot reported memory leaks [1] that I have back tracked to a missing cleanup from igmpv3_del_delrec() when (im->sfmode != MCAST_INCLUDE) Add ip_sf_list_clear_all() and kfree_pmc() helpers to explicitely handle the cleanups before freeing. [1] BUG: memory leak unreferenced object 0xffff888123e32b00 (size 64): comm "softirq", pid 0, jiffies 4294942968 (age 8.010s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 e0 00 00 01 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000006105011b>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline] [<000000006105011b>] slab_post_alloc_hook mm/slab.h:439 [inline] [<000000006105011b>] slab_alloc mm/slab.c:3326 [inline] [<000000006105011b>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553 [<000000004bba8073>] kmalloc include/linux/slab.h:547 [inline] [<000000004bba8073>] kzalloc include/linux/slab.h:742 [inline] [<000000004bba8073>] ip_mc_add1_src net/ipv4/igmp.c:1961 [inline] [<000000004bba8073>] ip_mc_add_src+0x36b/0x400 net/ipv4/igmp.c:2085 [<00000000a46a65a0>] ip_mc_msfilter+0x22d/0x310 net/ipv4/igmp.c:2475 [<000000005956ca89>] do_ip_setsockopt.isra.0+0x1795/0x1930 net/ipv4/ip_sockglue.c:957 [<00000000848e2d2f>] ip_setsockopt+0x3b/0xb0 net/ipv4/ip_sockglue.c:1246 [<00000000b9db185c>] udp_setsockopt+0x4e/0x90 net/ipv4/udp.c:2616 [<000000003028e438>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3130 [<0000000015b65589>] __sys_setsockopt+0x98/0x120 net/socket.c:2078 [<00000000ac198ef0>] __do_sys_setsockopt net/socket.c:2089 [inline] [<00000000ac198ef0>] __se_sys_setsockopt net/socket.c:2086 [inline] [<00000000ac198ef0>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2086 [<000000000a770437>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301 [<00000000d3adb93b>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 9c8bb163ae78 ("igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Hangbin Liu <liuhangbin@gmail.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/igmp.c')
-rw-r--r--net/ipv4/igmp.c47
1 files changed, 30 insertions, 17 deletions
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 6c2febc39dca..1a8d36dd49d4 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -633,6 +633,24 @@ static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
}
}
+static void ip_sf_list_clear_all(struct ip_sf_list *psf)
+{
+ struct ip_sf_list *next;
+
+ while (psf) {
+ next = psf->sf_next;
+ kfree(psf);
+ psf = next;
+ }
+}
+
+static void kfree_pmc(struct ip_mc_list *pmc)
+{
+ ip_sf_list_clear_all(pmc->sources);
+ ip_sf_list_clear_all(pmc->tomb);
+ kfree(pmc);
+}
+
static void igmpv3_send_cr(struct in_device *in_dev)
{
struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
@@ -669,7 +687,7 @@ static void igmpv3_send_cr(struct in_device *in_dev)
else
in_dev->mc_tomb = pmc_next;
in_dev_put(pmc->interface);
- kfree(pmc);
+ kfree_pmc(pmc);
} else
pmc_prev = pmc;
}
@@ -1215,14 +1233,18 @@ static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
im->interface = pmc->interface;
if (im->sfmode == MCAST_INCLUDE) {
im->tomb = pmc->tomb;
+ pmc->tomb = NULL;
+
im->sources = pmc->sources;
+ pmc->sources = NULL;
+
for (psf = im->sources; psf; psf = psf->sf_next)
psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
} else {
im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
}
in_dev_put(pmc->interface);
- kfree(pmc);
+ kfree_pmc(pmc);
}
spin_unlock_bh(&im->lock);
}
@@ -1243,21 +1265,18 @@ static void igmpv3_clear_delrec(struct in_device *in_dev)
nextpmc = pmc->next;
ip_mc_clear_src(pmc);
in_dev_put(pmc->interface);
- kfree(pmc);
+ kfree_pmc(pmc);
}
/* clear dead sources, too */
rcu_read_lock();
for_each_pmc_rcu(in_dev, pmc) {
- struct ip_sf_list *psf, *psf_next;
+ struct ip_sf_list *psf;
spin_lock_bh(&pmc->lock);
psf = pmc->tomb;
pmc->tomb = NULL;
spin_unlock_bh(&pmc->lock);
- for (; psf; psf = psf_next) {
- psf_next = psf->sf_next;
- kfree(psf);
- }
+ ip_sf_list_clear_all(psf);
}
rcu_read_unlock();
}
@@ -2123,7 +2142,7 @@ static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
static void ip_mc_clear_src(struct ip_mc_list *pmc)
{
- struct ip_sf_list *psf, *nextpsf, *tomb, *sources;
+ struct ip_sf_list *tomb, *sources;
spin_lock_bh(&pmc->lock);
tomb = pmc->tomb;
@@ -2135,14 +2154,8 @@ static void ip_mc_clear_src(struct ip_mc_list *pmc)
pmc->sfcount[MCAST_EXCLUDE] = 1;
spin_unlock_bh(&pmc->lock);
- for (psf = tomb; psf; psf = nextpsf) {
- nextpsf = psf->sf_next;
- kfree(psf);
- }
- for (psf = sources; psf; psf = nextpsf) {
- nextpsf = psf->sf_next;
- kfree(psf);
- }
+ ip_sf_list_clear_all(tomb);
+ ip_sf_list_clear_all(sources);
}
/* Join a multicast group