Description
In the Linux kernel, the following vulnerability has been resolved: net: bonding: fix NULL deref in bond_debug_rlb_hash_show rlb_clear_slave intentionally keeps RLB hash-table entries on the rx_hashtbl_used_head list with slave set to NULL when no replacement slave is available. However, bond_debug_rlb_hash_show visites client_info->slave without checking if it's NULL. Other used-list iterators in bond_alb.c already handle this NULL-slave state safely: - rlb_update_client returns early on !client_info->slave - rlb_req_update_slave_clients, rlb_clear_slave, and rlb_rebalance compare slave values before visiting - lb_req_update_subnet_clients continues if slave is NULL The following NULL deref crash can be trigger in bond_debug_rlb_hash_show: [ 1.289791] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 1.292058] RIP: 0010:bond_debug_rlb_hash_show (drivers/net/bonding/bond_debugfs.c:41) [ 1.293101] RSP: 0018:ffffc900004a7d00 EFLAGS: 00010286 [ 1.293333] RAX: 0000000000000000 RBX: ffff888102b48200 RCX: ffff888102b48204 [ 1.293631] RDX: ffff888102b48200 RSI: ffffffff839daad5 RDI: ffff888102815078 [ 1.293924] RBP: ffff888102815078 R08: ffff888102b4820e R09: 0000000000000000 [ 1.294267] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888100f929c0 [ 1.294564] R13: ffff888100f92a00 R14: 0000000000000001 R15: ffffc900004a7ed8 [ 1.294864] FS: 0000000001395380(0000) GS:ffff888196e75000(0000) knlGS:0000000000000000 [ 1.295239] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.295480] CR2: 0000000000000000 CR3: 0000000102adc004 CR4: 0000000000772ef0 [ 1.295897] Call Trace: [ 1.296134] seq_read_iter (fs/seq_file.c:231) [ 1.296341] seq_read (fs/seq_file.c:164) [ 1.296493] full_proxy_read (fs/debugfs/file.c:378 (discriminator 1)) [ 1.296658] vfs_read (fs/read_write.c:572) [ 1.296981] ksys_read (fs/read_write.c:717) [ 1.297132] do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) [ 1.297325] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) Add a NULL check and print "(none)" for entries with no assigned slave.
Product status
caafa84251b886feb6cdf23d50e2cc99dcdaaaf3 (git) before 19f0fd87df0e5746b24f5caa465a66a8c6e6e241
caafa84251b886feb6cdf23d50e2cc99dcdaaaf3 (git) before edacf1613f7b26423ebfa8b2892e7453c4235354
caafa84251b886feb6cdf23d50e2cc99dcdaaaf3 (git) before 2ec2c777f357a83c3d503d8d9370c90b60f0ae63
caafa84251b886feb6cdf23d50e2cc99dcdaaaf3 (git) before 0a3f8cd3f370247ded14d38d216b49dd30eade76
caafa84251b886feb6cdf23d50e2cc99dcdaaaf3 (git) before 6a3bb74e25d79cbb15f67ef80f71e2b2bfe27ff4
caafa84251b886feb6cdf23d50e2cc99dcdaaaf3 (git) before 017d674cf6930e9586a29ee808c7ca09d1396d07
caafa84251b886feb6cdf23d50e2cc99dcdaaaf3 (git) before ec9762f0df2f9fbe3f40a3bfa8aab8b2f721466c
caafa84251b886feb6cdf23d50e2cc99dcdaaaf3 (git) before 605b52497bf89b3b154674deb135da98f916e390
2.6.38
Any version before 2.6.38
5.10.253 (semver)
5.15.203 (semver)
6.1.167 (semver)
6.6.130 (semver)
6.12.78 (semver)
6.18.20 (semver)
6.19.10 (semver)
7.0 (original_commit_for_fix)
References
git.kernel.org/...c/19f0fd87df0e5746b24f5caa465a66a8c6e6e241
git.kernel.org/...c/edacf1613f7b26423ebfa8b2892e7453c4235354
git.kernel.org/...c/2ec2c777f357a83c3d503d8d9370c90b60f0ae63
git.kernel.org/...c/0a3f8cd3f370247ded14d38d216b49dd30eade76
git.kernel.org/...c/6a3bb74e25d79cbb15f67ef80f71e2b2bfe27ff4
git.kernel.org/...c/017d674cf6930e9586a29ee808c7ca09d1396d07
git.kernel.org/...c/ec9762f0df2f9fbe3f40a3bfa8aab8b2f721466c
git.kernel.org/...c/605b52497bf89b3b154674deb135da98f916e390