From daf9de90e88ffb2e303145733167327f92b869c2 Mon Sep 17 00:00:00 2001 From: Ryan Sullivan Date: Tue, 7 Feb 2023 12:08:05 -0500 Subject: [KPATCH CVE-2022-4378] kpatch fixes for CVE-2022-4378 Kernels: 4.18.0-425.3.1.el8 4.18.0-425.10.1.el8_7 Kpatch-MR: https://gitlab.com/redhat/prdsc/rhel/src/kpatch/rhel-8/-/merge_requests/82 Approved-by: Joe Lawrence (@joe.lawrence) Approved-by: Yannick Cote (@ycote1) Changes since last build: [x86_64]: control.o: changed function: snd_ctl_elem_read control.o: changed function: snd_ctl_ioctl sysctl.o: changed function: __do_proc_dointvec sysctl.o: changed function: __do_proc_douintvec sysctl.o: changed function: __do_proc_doulongvec_minmax sysctl.o: changed function: proc_get_long.constprop.14 [ppc64le]: control.o: changed function: snd_ctl_elem_read control.o: changed function: snd_ctl_ioctl sysctl.o: changed function: __do_proc_dointvec sysctl.o: changed function: __do_proc_doulongvec_minmax sysctl.o: changed function: proc_dopipe_max_size sysctl.o: changed function: proc_douintvec sysctl.o: changed function: proc_douintvec_minmax sysctl.o: changed function: proc_get_long.constprop.14 --------------------------- Modifications: none commit 8c873c04cfd546b8b29ae86dc35414cf4167d163 Author: Wander Lairson Costa Date: Mon Dec 12 15:43:15 2022 -0300 proc: avoid integer type confusion in get_proc_long Bugzilla: https://bugzilla.redhat.com/2152571 CVE: CVE-2022-4378 Y-Commit: bbda4302821f46972d5139f9af87993a7a07306e O-Bugzilla: https://bugzilla.redhat.com/2152572 O-CVE: CVE-2022-4378 commit e6cfaf34be9fcd1a8285a294e18986bfc41a409c Author: Linus Torvalds Date: Mon Dec 5 11:33:40 2022 -0800 proc: avoid integer type confusion in get_proc_long proc_get_long() is passed a size_t, but then assigns it to an 'int' variable for the length. Let's not do that, even if our IO paths are limited to MAX_RW_COUNT (exactly because of these kinds of type errors). So do the proper test in the rigth type. Reported-by: Kyle Zeng Signed-off-by: Linus Torvalds Signed-off-by: Wander Lairson Costa Signed-off-by: Jarod Wilson commit 2347e6da850ca59e4730578b53d0e9339a1bb1e6 Author: Wander Lairson Costa Date: Mon Dec 12 15:47:25 2022 -0300 proc: proc_skip_spaces() shouldn't think it is working on C strings Bugzilla: https://bugzilla.redhat.com/2152571 CVE: CVE-2022-4378 Y-Commit: ec2f9f80ba44b533578349a97fb2fe9894142221 O-Bugzilla: https://bugzilla.redhat.com/2152572 O-CVE: CVE-2022-4378 Conflicts: context hunks because out version is much older than upstream. commit bce9332220bd677d83b19d21502776ad555a0e73 Author: Linus Torvalds Date: Mon Dec 5 12:09:06 2022 -0800 proc: proc_skip_spaces() shouldn't think it is working on C strings proc_skip_spaces() seems to think it is working on C strings, and ends up being just a wrapper around skip_spaces() with a really odd calling convention. Instead of basing it on skip_spaces(), it should have looked more like proc_skip_char(), which really is the exact same function (except it skips a particular character, rather than whitespace). So use that as inspiration, odd coding and all. Now the calling convention actually makes sense and works for the intended purpose. Reported-and-tested-by: Kyle Zeng Acked-by: Eric Dumazet Signed-off-by: Linus Torvalds Signed-off-by: Wander Lairson Costa Signed-off-by: Jarod Wilson Signed-off-by: Ryan Sullivan --- kernel/sysctl.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index b4c8a670e9e0..3c8a3a787528 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -2194,13 +2194,14 @@ int proc_dostring(struct ctl_table *table, int write, (char __user *)buffer, lenp, ppos); } -static size_t proc_skip_spaces(char **buf) +static void proc_skip_spaces(char **buf, size_t *size) { - size_t ret; - char *tmp = skip_spaces(*buf); - ret = tmp - *buf; - *buf = tmp; - return ret; + while (*size) { + if (!isspace(**buf)) + break; + (*size)--; + (*buf)++; + } } static void proc_skip_char(char **buf, size_t *size, const char v) @@ -2269,13 +2270,12 @@ static int proc_get_long(char **buf, size_t *size, unsigned long *val, bool *neg, const char *perm_tr, unsigned perm_tr_len, char *tr) { - int len; char *p, tmp[TMPBUFLEN]; + ssize_t len = *size; - if (!*size) + if (len <= 0) return -EINVAL; - len = *size; if (len > TMPBUFLEN - 1) len = TMPBUFLEN - 1; @@ -2438,7 +2438,7 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table, bool neg; if (write) { - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); if (!left) break; @@ -2469,7 +2469,7 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table, if (!write && !first && left && !err) err = proc_put_char(&buffer, &left, '\n'); if (write && !err && left) - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); if (write) { kfree(kbuf); if (first) @@ -2518,7 +2518,7 @@ static int do_proc_douintvec_w(unsigned int *tbl_data, if (IS_ERR(kbuf)) return -EINVAL; - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); if (!left) { err = -EINVAL; goto out_free; @@ -2538,7 +2538,7 @@ static int do_proc_douintvec_w(unsigned int *tbl_data, } if (!err && left) - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); out_free: kfree(kbuf); @@ -2982,7 +2982,7 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int if (write) { bool neg; - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); err = proc_get_long(&p, &left, &val, &neg, proc_wspace_sep, @@ -3013,7 +3013,7 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int if (!write && !first && left && !err) err = proc_put_char(&buffer, &left, '\n'); if (write && !err) - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); if (write) { kfree(kbuf); if (first) -- 2.39.2