user/sven/linux.git/security/apparmor/lib.c, branch v4.19.135

apparmor: Fix uninitialized value in aa_split_fqname

2018-11-27T15:13:00Z

[ Upstream commit 250f2da49cb8e582215a65c03f50e8ddf5cd119c ] Syzkaller reported a OOB-read with the stacktrace below. This occurs inside __aa_lookupn_ns as `n` is not initialized. `n` is obtained from aa_splitn_fqname. In cases where `name` is invalid, aa_splitn_fqname returns without initializing `ns_name` and `ns_len`. Fix this by always initializing `ns_name` and `ns_len`. __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 memcmp+0xe3/0x160 lib/string.c:861 strnstr+0x4b/0x70 lib/string.c:934 __aa_lookupn_ns+0xc1/0x570 security/apparmor/policy_ns.c:209 aa_lookupn_ns+0x88/0x1e0 security/apparmor/policy_ns.c:240 aa_fqlookupn_profile+0x1b9/0x1010 security/apparmor/policy.c:468 fqlookupn_profile+0x80/0xc0 security/apparmor/label.c:1844 aa_label_strn_parse+0xa3a/0x1230 security/apparmor/label.c:1908 aa_label_parse+0x42/0x50 security/apparmor/label.c:1943 aa_change_profile+0x513/0x3510 security/apparmor/domain.c:1362 apparmor_setprocattr+0xaa4/0x1150 security/apparmor/lsm.c:658 security_setprocattr+0x66/0xc0 security/security.c:1298 proc_pid_attr_write+0x301/0x540 fs/proc/base.c:2555 __vfs_write+0x119/0x9f0 fs/read_write.c:485 vfs_write+0x1fc/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 3b0aaf5866bf ("apparmor: add lib fn to find the "split" for fqnames") Reported-by: syzbot+61e4b490d9d2da591b50@syzkaller.appspotmail.com Signed-off-by: Zubin Mithra Reviewed-by: Kees Cook Signed-off-by: John Johansen Signed-off-by: Sasha Levin

apparmor: Check buffer bounds when mapping permissions mask

2018-07-19T23:24:43Z

Don't read past the end of the buffer containing permissions characters or write past the end of the destination string. Detected by CoverityScan CID#1415361, 1415376 ("Out-of-bounds access") Fixes: e53cfe6c7caa ("apparmor: rework perm mapping to a slightly broader set") Signed-off-by: Tyler Hicks Acked-by: Serge Hallyn Signed-off-by: John Johansen

apparmor: fix typo "type"

2018-05-03T07:49:56Z

Signed-off-by: Zygmunt Krynicki Acked-by: Christian Boltz Signed-off-by: John Johansen

apparmor: add base infastructure for socket mediation

2018-03-14T00:25:48Z

apparmor: remove unused redundant variable stop

2017-11-21T10:17:13Z

The boolean variable 'stop' is being set but never read. This is a redundant variable and can be removed. Cleans up clang warning: Value stored to 'stop' is never read Signed-off-by: Colin Ian King Signed-off-by: John Johansen

apparmor: initialized returned struct aa_perms

2017-11-21T10:15:50Z

gcc-4.4 points out suspicious code in compute_mnt_perms, where the aa_perms structure is only partially initialized before getting returned: security/apparmor/mount.c: In function 'compute_mnt_perms': security/apparmor/mount.c:227: error: 'perms.prompt' is used uninitialized in this function security/apparmor/mount.c:227: error: 'perms.hide' is used uninitialized in this function security/apparmor/mount.c:227: error: 'perms.cond' is used uninitialized in this function security/apparmor/mount.c:227: error: 'perms.complain' is used uninitialized in this function security/apparmor/mount.c:227: error: 'perms.stop' is used uninitialized in this function security/apparmor/mount.c:227: error: 'perms.deny' is used uninitialized in this function Returning or assigning partially initialized structures is a bit tricky, in particular it is explicitly allowed in c99 to assign a partially initialized structure to another, as long as only members are read that have been initialized earlier. Looking at what various compilers do here, the version that produced the warning copied uninitialized stack data, while newer versions (and also clang) either set the other members to zero or don't update the parts of the return buffer that are not modified in the temporary structure, but they never warn about this. In case of apparmor, it seems better to be a little safer and always initialize the aa_perms structure. Most users already do that, this changes the remaining ones, including the one instance that I got the warning for. Fixes: fa488437d0f9 ("apparmor: add mount mediation") Signed-off-by: Arnd Bergmann Reviewed-by: Seth Arnold Acked-by: Geert Uytterhoeven Signed-off-by: John Johansen

Revert "apparmor: add base infastructure for socket mediation"

2017-10-26T17:35:35Z

This reverts commit 651e28c5537abb39076d3949fb7618536f1d242e. This caused a regression: "The specific problem is that dnsmasq refuses to start on openSUSE Leap 42.2. The specific cause is that and attempt to open a PF_LOCAL socket gets EACCES. This means that networking doesn't function on a system with a 4.14-rc2 system." Sadly, the developers involved seemed to be in denial for several weeks about this, delaying the revert. This has not been a good release for the security subsystem, and this area needs to change development practices. Reported-and-bisected-by: James Bottomley Tracked-by: Thorsten Leemhuis Cc: John Johansen Cc: Vlastimil Babka Cc: Seth Arnold Signed-off-by: Linus Torvalds

apparmor: add base infastructure for socket mediation

2017-09-22T20:00:58Z

apparmor: switch from profiles to using labels on contexts

2017-06-11T00:11:38Z

Begin the actual switch to using domain labels by storing them on the context and converting the label to a singular profile where possible. Signed-off-by: John Johansen

apparmor: share profile name on replacement

2017-06-11T00:11:35Z

The profile names are the same, leverage this. Signed-off-by: John Johansen