The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=555a861d6826eca8710e361ee4d0ef29b28f39d2
commit 555a861d6826eca8710e361ee4d0ef29b28f39d2 Author: Konstantin Belousov <[email protected]> AuthorDate: 2022-10-08 00:08:14 +0000 Commit: Konstantin Belousov <[email protected]> CommitDate: 2022-10-19 16:39:40 +0000 device_get_path(): take sbuf directly This allows to fix a bug where sbuf allocation done in the context of dev_wired_cache_match() must use non-sleepable allocations. Suggested by: jhb Reviewed by: jhb, takawata Discussed with: imp Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D36899 --- sys/kern/subr_bus.c | 73 +++++++++++++++++++++++++---------------------------- 1 file changed, 35 insertions(+), 38 deletions(-) diff --git a/sys/kern/subr_bus.c b/sys/kern/subr_bus.c index 74bc47174d8d..5c165419af2d 100644 --- a/sys/kern/subr_bus.c +++ b/sys/kern/subr_bus.c @@ -5305,37 +5305,24 @@ device_do_deferred_actions(void) } static int -device_get_path(device_t dev, const char *locator, char **rvp) +device_get_path(device_t dev, const char *locator, struct sbuf *sb) { - struct sbuf *sb; - char *s; device_t parent; - ssize_t len; int error; + sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); parent = device_get_parent(dev); if (parent == NULL) { - *rvp = strdup_flags("/", M_BUS, M_NOWAIT); - return (*rvp == NULL ? ENOMEM : 0); - } - sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); - error = BUS_GET_DEVICE_PATH(parent, dev, locator, sb); - sbuf_finish(sb); /* Note: errors checked with sbuf_len() below */ - if (error == 0) { - len = sbuf_len(sb); - if (len <= 1) { - error = EIO; - } else { - s = malloc(len, M_BUS, M_NOWAIT); - if (s == NULL) { - error = ENOMEM; - } else { - memcpy(s, sbuf_data(sb), len); - *rvp = s; - } + error = sbuf_printf(sb, "/"); + } else { + error = BUS_GET_DEVICE_PATH(parent, dev, locator, sb); + if (error == 0) { + error = sbuf_error(sb); + if (error == 0 && sbuf_len(sb) <= 1) + error = EIO; } } - sbuf_delete(sb); + sbuf_finish(sb); return (error); } @@ -5599,25 +5586,28 @@ devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag, req->dr_flags); break; case DEV_GET_PATH: { + struct sbuf *sb; char locator[64]; - char *path; ssize_t len; error = copyinstr(req->dr_buffer.buffer, locator, sizeof(locator), NULL); if (error != 0) break; - error = device_get_path(dev, locator, &path); - if (error != 0) - break; - len = strlen(path) + 1; - if (req->dr_buffer.length < len) { - error = ENAMETOOLONG; - } else { - error = copyout(path, req->dr_buffer.buffer, len); + sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND | + SBUF_INCLUDENUL /* | SBUF_WAITOK */); + error = device_get_path(dev, locator, sb); + if (error == 0) { + len = sbuf_len(sb); + if (req->dr_buffer.length < len) { + error = ENAMETOOLONG; + } else { + error = copyout(sbuf_data(sb), + req->dr_buffer.buffer, len); + } + req->dr_buffer.length = len; } - req->dr_buffer.length = len; - free(path, M_BUS); + sbuf_delete(sb); break; } } @@ -5712,8 +5702,8 @@ bool dev_wired_cache_match(device_location_cache_t *dcp, device_t dev, const char *at) { + struct sbuf *sb; const char *cp; - char *path; char locator[32]; int error, len; struct device_location_node *res; @@ -5732,9 +5722,16 @@ dev_wired_cache_match(device_location_cache_t *dcp, device_t dev, /* maybe cache this inside device_t and look that up, but not yet */ res = dev_wired_cache_lookup(dcp, locator); if (res == NULL) { - error = device_get_path(dev, locator, &path); - if (error == 0) - res = dev_wired_cache_add(dcp, locator, path); + sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND | + SBUF_INCLUDENUL | SBUF_NOWAIT); + if (sb != NULL) { + error = device_get_path(dev, locator, sb); + if (error == 0) { + res = dev_wired_cache_add(dcp, locator, + sbuf_data(sb)); + } + sbuf_delete(sb); + } } if (error != 0 || res == NULL || res->dln_path == NULL) return (false);
