CVE-2024-39487

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> bonding: Fix out-of-bounds read in bond_option_arp_ip_targets_set()<br /> <br /> In function bond_option_arp_ip_targets_set(), if newval-&gt;string is an<br /> empty string, newval-&gt;string+1 will point to the byte after the<br /> string, causing an out-of-bound read.<br /> <br /> BUG: KASAN: slab-out-of-bounds in strlen+0x7d/0xa0 lib/string.c:418<br /> Read of size 1 at addr ffff8881119c4781 by task syz-executor665/8107<br /> CPU: 1 PID: 8107 Comm: syz-executor665 Not tainted 6.7.0-rc7 #1<br /> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014<br /> Call Trace:<br /> <br /> __dump_stack lib/dump_stack.c:88 [inline]<br /> dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106<br /> print_address_description mm/kasan/report.c:364 [inline]<br /> print_report+0xc1/0x5e0 mm/kasan/report.c:475<br /> kasan_report+0xbe/0xf0 mm/kasan/report.c:588<br /> strlen+0x7d/0xa0 lib/string.c:418<br /> __fortify_strlen include/linux/fortify-string.h:210 [inline]<br /> in4_pton+0xa3/0x3f0 net/core/utils.c:130<br /> bond_option_arp_ip_targets_set+0xc2/0x910<br /> drivers/net/bonding/bond_options.c:1201<br /> __bond_opt_set+0x2a4/0x1030 drivers/net/bonding/bond_options.c:767<br /> __bond_opt_set_notify+0x48/0x150 drivers/net/bonding/bond_options.c:792<br /> bond_opt_tryset_rtnl+0xda/0x160 drivers/net/bonding/bond_options.c:817<br /> bonding_sysfs_store_option+0xa1/0x120 drivers/net/bonding/bond_sysfs.c:156<br /> dev_attr_store+0x54/0x80 drivers/base/core.c:2366<br /> sysfs_kf_write+0x114/0x170 fs/sysfs/file.c:136<br /> kernfs_fop_write_iter+0x337/0x500 fs/kernfs/file.c:334<br /> call_write_iter include/linux/fs.h:2020 [inline]<br /> new_sync_write fs/read_write.c:491 [inline]<br /> vfs_write+0x96a/0xd80 fs/read_write.c:584<br /> ksys_write+0x122/0x250 fs/read_write.c:637<br /> do_syscall_x64 arch/x86/entry/common.c:52 [inline]<br /> do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83<br /> entry_SYSCALL_64_after_hwframe+0x63/0x6b<br /> ---[ end trace ]---<br /> <br /> Fix it by adding a check of string length before using it.